Merge branch 'main' into mantine-ui

Signed-off-by: Julius Volz <julius.volz@gmail.com>

.github/stale.yml

@@ -1,56 +0,0 @@
-# Configuration for probot-stale - https://github.com/probot/stale
-
-# Number of days of inactivity before an Issue or Pull Request becomes stale
-daysUntilStale: 60
-
-# Number of days of inactivity before an Issue or Pull Request with the stale label is closed.
-# Set to false to disable. If disabled, issues still need to be closed manually, but will remain marked as stale.
-daysUntilClose: false
-
-# Only issues or pull requests with all of these labels are check if stale. Defaults to `[]` (disabled)
-onlyLabels: []
-
-# Issues or Pull Requests with these labels will never be considered stale. Set to `[]` to disable
-exemptLabels:
-  - keepalive
-
-# Set to true to ignore issues in a project (defaults to false)
-exemptProjects: false
-
-# Set to true to ignore issues in a milestone (defaults to false)
-exemptMilestones: false
-
-# Set to true to ignore issues with an assignee (defaults to false)
-exemptAssignees: false
-
-# Label to use when marking as stale
-staleLabel: stale
-
-# Comment to post when marking as stale. Set to `false` to disable
-markComment: false
-
-# Comment to post when removing the stale label.
-# unmarkComment: >
-#   Your comment here.
-
-# Comment to post when closing a stale Issue or Pull Request.
-# closeComment: >
-#   Your comment here.
-
-# Limit the number of actions per hour, from 1-30. Default is 30
-limitPerRun: 30
-
-# Limit to only `issues` or `pulls`
-only: pulls
-
-# Optionally, specify configuration settings that are specific to just 'issues' or 'pulls':
-# pulls:
-#   daysUntilStale: 30
-#   markComment: >
-#     This pull request has been automatically marked as stale because it has not had
-#     recent activity. It will be closed if no further activity occurs. Thank you
-#     for your contributions.
-
-# issues:
-#   exemptLabels:
-#     - confirmed

.github/workflows/buf-lint.yml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: bufbuild/buf-setup-action@35c243d7f2a909b1d4e40399b348a7fdab27d78d # v1.34.0
+      - uses: bufbuild/buf-setup-action@54abbed4fe8d8d45173eca4798b0c39a53a7b658 # v1.39.0
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
       - uses: bufbuild/buf-lint-action@06f9dd823d873146471cfaaf108a993fe00e5325 # v1.1.1

.github/workflows/buf.yml

@@ -13,7 +13,7 @@ jobs:
     if: github.repository_owner == 'prometheus'
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: bufbuild/buf-setup-action@35c243d7f2a909b1d4e40399b348a7fdab27d78d # v1.34.0
+      - uses: bufbuild/buf-setup-action@54abbed4fe8d8d45173eca4798b0c39a53a7b658 # v1.39.0
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
       - uses: bufbuild/buf-lint-action@06f9dd823d873146471cfaaf108a993fe00e5325 # v1.1.1

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
       image: quay.io/prometheus/golang-builder:1.22-base
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: prometheus/promci@3cb0c3871f223bd5ce1226995bd52ffb314798b6 # v0.1.0
+      - uses: prometheus/promci@45166329da36d74895901808f1c8c97efafc7f84 # v0.3.0
       - uses: ./.github/promci/actions/setup_environment
       - run: make GOOPTS=--tags=stringlabels GO_ONLY=1 SKIP_GOLANGCI_LINT=1
       - run: go test --tags=stringlabels ./tsdb/ -test.tsdb-isolation=false
@@ -28,7 +28,7 @@ jobs:
       image: quay.io/prometheus/golang-builder:1.22-base
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: prometheus/promci@3cb0c3871f223bd5ce1226995bd52ffb314798b6 # v0.1.0
+      - uses: prometheus/promci@45166329da36d74895901808f1c8c97efafc7f84 # v0.3.0
       - uses: ./.github/promci/actions/setup_environment
       - run: go test --tags=dedupelabels ./...
       - run: GOARCH=386 go test ./cmd/prometheus
@@ -58,7 +58,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: prometheus/promci@3cb0c3871f223bd5ce1226995bd52ffb314798b6 # v0.1.0
+      - uses: prometheus/promci@45166329da36d74895901808f1c8c97efafc7f84 # v0.3.0
       - uses: ./.github/promci/actions/setup_environment
         with:
           enable_go: false
@@ -75,7 +75,7 @@ jobs:
     runs-on: windows-latest
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: actions/setup-go@cdcb36043654635271a94b9a6d1392de5bb323a7 # v5.0.1
+      - uses: actions/setup-go@0a12ed9d6a96ab950c8f026ed9f722fe0da7ef32 # v5.0.2
         with:
           go-version: 1.22.x
       - run: |
@@ -115,7 +115,7 @@ jobs:
         thread: [ 0, 1, 2 ]
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: prometheus/promci@3cb0c3871f223bd5ce1226995bd52ffb314798b6 # v0.1.0
+      - uses: prometheus/promci@45166329da36d74895901808f1c8c97efafc7f84 # v0.3.0
       - uses: ./.github/promci/actions/build
         with:
           promu_opts: "-p linux/amd64 -p windows/amd64 -p linux/arm64 -p darwin/amd64 -p darwin/arm64 -p linux/386"
@@ -138,7 +138,7 @@ jobs:
     # should also be updated.
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: prometheus/promci@3cb0c3871f223bd5ce1226995bd52ffb314798b6 # v0.1.0
+      - uses: prometheus/promci@45166329da36d74895901808f1c8c97efafc7f84 # v0.3.0
       - uses: ./.github/promci/actions/build
         with:
           parallelism: 12
@@ -162,7 +162,7 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
       - name: Install Go
-        uses: actions/setup-go@cdcb36043654635271a94b9a6d1392de5bb323a7 # v5.0.1
+        uses: actions/setup-go@0a12ed9d6a96ab950c8f026ed9f722fe0da7ef32 # v5.0.2
         with:
           cache: false
           go-version: 1.22.x
@@ -175,18 +175,18 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
       - name: Install Go
-        uses: actions/setup-go@cdcb36043654635271a94b9a6d1392de5bb323a7 # v5.0.1
+        uses: actions/setup-go@0a12ed9d6a96ab950c8f026ed9f722fe0da7ef32 # v5.0.2
         with:
           go-version: 1.22.x
       - name: Install snmp_exporter/generator dependencies
         run: sudo apt-get update && sudo apt-get -y install libsnmp-dev
         if: github.repository == 'prometheus/snmp_exporter'
       - name: Lint
-        uses: golangci/golangci-lint-action@a4f60bb28d35aeee14e6880718e0c85ff1882e64 # v6.0.1
+        uses: golangci/golangci-lint-action@aaa42aa0628b4ae2578232a66b541047968fac86 # v6.1.0
         with:
           args: --verbose
           # Make sure to sync this with Makefile.common and scripts/golangci-lint.yml.
-          version: v1.59.1
+          version: v1.60.2
   fuzzing:
     uses: ./.github/workflows/fuzzing.yml
     if: github.event_name == 'pull_request'
@@ -200,7 +200,7 @@ jobs:
     if: github.event_name == 'push' && github.event.ref == 'refs/heads/main'
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: prometheus/promci@3cb0c3871f223bd5ce1226995bd52ffb314798b6 # v0.1.0
+      - uses: prometheus/promci@45166329da36d74895901808f1c8c97efafc7f84 # v0.3.0
       - uses: ./.github/promci/actions/publish_main
         with:
           docker_hub_login: ${{ secrets.docker_hub_login }}
@@ -214,7 +214,7 @@ jobs:
     if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v2.')
     steps:
       - uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: prometheus/promci@3cb0c3871f223bd5ce1226995bd52ffb314798b6 # v0.1.0
+      - uses: prometheus/promci@45166329da36d74895901808f1c8c97efafc7f84 # v0.3.0
       - uses: ./.github/promci/actions/publish_release
         with:
           docker_hub_login: ${{ secrets.docker_hub_login }}
@@ -229,9 +229,9 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
-      - uses: prometheus/promci@3cb0c3871f223bd5ce1226995bd52ffb314798b6 # v0.1.0
+      - uses: prometheus/promci@45166329da36d74895901808f1c8c97efafc7f84 # v0.3.0
       - name: Install nodejs
-        uses: actions/setup-node@60edb5dd545a775178f52524783378180af0d1f8 # v4.0.2
+        uses: actions/setup-node@1e60f620b9541d16bece96c5465dc8ee9832be0b # v4.0.3
         with:
           node-version-file: "web/ui/.nvmrc"
           registry-url: "https://registry.npmjs.org"

.github/workflows/codeql-analysis.yml

@@ -27,12 +27,12 @@ jobs:
         uses: actions/checkout@a5ac7e51b41094c92402da3b24376905380afc29 # v4.1.6
 
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@b611370bb5703a7efb587f9d136a52ea24c5c38c # v3.25.11
+        uses: github/codeql-action/init@4dd16135b69a43b6c8efb853346f8437d92d3c93 # v3.26.6
         with:
           languages: ${{ matrix.language }}
 
       - name: Autobuild
-        uses: github/codeql-action/autobuild@b611370bb5703a7efb587f9d136a52ea24c5c38c # v3.25.11
+        uses: github/codeql-action/autobuild@4dd16135b69a43b6c8efb853346f8437d92d3c93 # v3.26.6
 
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@b611370bb5703a7efb587f9d136a52ea24c5c38c # v3.25.11
+        uses: github/codeql-action/analyze@4dd16135b69a43b6c8efb853346f8437d92d3c93 # v3.26.6

.github/workflows/fuzzing.yml

@@ -21,7 +21,7 @@ jobs:
           fuzz-seconds: 600
           dry-run: false
       - name: Upload Crash
-        uses: actions/upload-artifact@65462800fd760344b1a7b4382951275a0abb4808 # v4.3.3
+        uses: actions/upload-artifact@0b2256b8c012f0828dc542b3febcab082c67f72b # v4.3.4
         if: failure() && steps.build.outcome == 'success'
         with:
           name: artifacts

.github/workflows/scorecards.yml

@@ -26,7 +26,7 @@ jobs:
           persist-credentials: false
 
       - name: "Run analysis"
-        uses: ossf/scorecard-action@dc50aa9510b46c811795eb24b2f1ba02a914e534 # tag=v2.3.3
+        uses: ossf/scorecard-action@62b2cac7ed8198b15735ed49ab1e5cf35480ba46 # tag=v2.4.0
         with:
           results_file: results.sarif
           results_format: sarif
@@ -37,7 +37,7 @@ jobs:
       # Upload the results as artifacts (optional). Commenting out will disable uploads of run results in SARIF
       # format to the repository Actions tab.
       - name: "Upload artifact"
-        uses: actions/upload-artifact@65462800fd760344b1a7b4382951275a0abb4808 # tag=v4.3.3
+        uses: actions/upload-artifact@0b2256b8c012f0828dc542b3febcab082c67f72b # tag=v4.3.4
         with:
           name: SARIF file
           path: results.sarif
@@ -45,6 +45,6 @@ jobs:
 
       # Upload the results to GitHub's code scanning dashboard.
       - name: "Upload to code-scanning"
-        uses: github/codeql-action/upload-sarif@b611370bb5703a7efb587f9d136a52ea24c5c38c # tag=v3.25.11
+        uses: github/codeql-action/upload-sarif@4dd16135b69a43b6c8efb853346f8437d92d3c93 # tag=v3.26.6
         with:
           sarif_file: results.sarif

.github/workflows/stale.yml

@@ -0,0 +1,31 @@
+name: Stale Check
+on:
+  workflow_dispatch: {}
+  schedule:
+    - cron: '16 22 * * *'
+permissions:
+  issues: write
+  pull-requests: write
+jobs:
+  stale:
+    if: github.repository_owner == 'prometheus' || github.repository_owner == 'prometheus-community' # Don't run this workflow on forks.
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@28ca1036281a5e5922ead5184a1bbf96e5fc984e # v9.0.0
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          # opt out of defaults to avoid marking issues as stale and closing them
+          # https://github.com/actions/stale#days-before-close
+          # https://github.com/actions/stale#days-before-stale
+          days-before-stale: -1
+          days-before-close: -1
+          # Setting it to empty string to skip comments.
+          # https://github.com/actions/stale#stale-pr-message
+          # https://github.com/actions/stale#stale-issue-message
+          stale-pr-message: ''
+          stale-issue-message: ''
+          operations-per-run: 30
+          # override days-before-stale, for only marking the pull requests as stale
+          days-before-pr-stale: 60
+          stale-pr-label: stale
+          exempt-pr-labels: keepalive

.golangci.yml

@@ -25,15 +25,34 @@ linters:
     - loggercheck
 
 issues:
+  max-issues-per-linter: 0
   max-same-issues: 0
+  # The default exclusions are too aggressive. For one, they
+  # essentially disable any linting on doc comments. We disable
+  # default exclusions here and add exclusions fitting our codebase
+  # further down.
+  exclude-use-default: false
   exclude-files:
     # Skip autogenerated files.
     - ^.*\.(pb|y)\.go$
   exclude-dirs:
-    # Copied it from a different source
+    # Copied it from a different source.
     - storage/remote/otlptranslator/prometheusremotewrite
     - storage/remote/otlptranslator/prometheus
   exclude-rules:
+    - linters:
+        - errcheck
+      # Taken from the default exclusions (that are otherwise disabled above).
+      text: Error return value of .((os\.)?std(out|err)\..*|.*Close|.*Flush|os\.Remove(All)?|.*print(f|ln)?|os\.(Un)?Setenv). is not checked
+    - linters:
+        - govet
+      # We use many Seek methods that do not follow the usual pattern.
+      text: "stdmethods: method Seek.* should have signature Seek"
+    - linters:
+        - revive
+      # We have stopped at some point to write doc comments on exported symbols.
+      # TODO(beorn7): Maybe we should enforce this again? There are ~500 offenders right now.
+      text: exported (.+) should have comment( \(or a comment on this block\))? or be unexported
     - linters:
         - gocritic
       text: "appendAssign"
@@ -94,15 +113,14 @@ linters-settings:
     errorf: false
   revive:
     # By default, revive will enable only the linting rules that are named in the configuration file.
-    # So, it's needed to explicitly set in configuration all required rules.
+    # So, it's needed to explicitly enable all required rules here.
-    # The following configuration enables all the rules from the defaults.toml
-    # https://github.com/mgechev/revive/blob/master/defaults.toml
     rules:
       # https://github.com/mgechev/revive/blob/master/RULES_DESCRIPTIONS.md
       - name: blank-imports
+      - name: comment-spacings
       - name: context-as-argument
         arguments:
-          # allow functions with test or bench signatures
+          # Allow functions with test or bench signatures.
           - allowTypesBefore: "*testing.T,testing.TB"
       - name: context-keys-type
       - name: dot-imports
@@ -118,6 +136,8 @@ linters-settings:
       - name: increment-decrement
       - name: indent-error-flow
       - name: package-comments
+        # TODO(beorn7): Currently, we have a lot of missing package doc comments. Maybe we should have them.
+        disabled: true
       - name: range
       - name: receiver-naming
       - name: redefines-builtin-id

CHANGELOG.md

@@ -3,8 +3,59 @@
 ## unreleased
 
 * [FEATURE] OTLP receiver: Add new option `otlp.promote_resource_attributes`, for any OTel resource attributes that should be promoted to metric labels. #14200
-* [FEATURE] Remote-Write: Add sender and receiver support for [Remote Write 2.0-rc.2](https://prometheus.io/docs/specs/remote_write_spec_2_0/) specification #14395 #14427 #14444
+* [ENHANCEMENT] OTLP receiver: Warn when encountering exponential histograms with zero count and non-zero sum. #14706
-* [ENHANCEMENT] Remote-Write: 1.x messages against Remote Write 2.x Receivers will have now correct values for `prometheus_storage_<samples|histograms|exemplar>_failed_total` in case of partial errors #14444
+* [BUGFIX] tsdb/wlog.Watcher.readSegmentForGC: Only count unknown record types against record_decode_failures_total metric. #14042
+
+## 2.54.1 / 2024-08-27
+
+* [BUGFIX] Scraping: allow multiple samples on same series, with explicit timestamps. #14685
+* [BUGFIX] Docker SD: fix crash in `match_first_network` mode when container is reconnected to a new network. #14654
+* [BUGFIX] PromQL: fix experimental native histograms getting corrupted due to vector selector bug in range queries. #14538
+* [BUGFIX] PromQL: fix experimental native histogram counter reset detection on stale samples. #14514
+* [BUGFIX] PromQL: fix native histograms getting corrupted due to vector selector bug in range queries. #14605
+
+## 2.54.0 / 2024-08-09
+
+Release 2.54 brings a release candidate of a major new version of [Remote Write: 2.0](https://prometheus.io/docs/specs/remote_write_spec_2_0/).
+This is experimental at this time and may still change.
+Remote-write v2 is enabled by default, but can be disabled via feature-flag `web.remote-write-receiver.accepted-protobuf-messages`.
+
+* [CHANGE] Remote-Write: `highest_timestamp_in_seconds` and `queue_highest_sent_timestamp_seconds` metrics now initialized to 0. #14437
+* [CHANGE] API: Split warnings from info annotations in API response. #14327
+* [FEATURE] Remote-Write: Version 2.0 experimental, plus metadata in WAL via feature flag `metadata-wal-records` (defaults on). #14395,#14427,#14444
+* [FEATURE] PromQL: add limitk() and limit_ratio() aggregation operators. #12503
+* [ENHANCEMENT] PromQL: Accept underscores in literal numbers, e.g. 1_000_000 for 1 million. #12821
+* [ENHANCEMENT] PromQL: float literal numbers and durations are now interchangeable (experimental). Example: `time() - my_timestamp > 10m`. #9138
+* [ENHANCEMENT] PromQL: use Kahan summation for sum(). #14074,#14362
+* [ENHANCEMENT] PromQL (experimental native histograms): Optimize `histogram_count` and `histogram_sum` functions. #14097
+* [ENHANCEMENT] TSDB: Better support for out-of-order experimental native histogram samples. #14438
+* [ENHANCEMENT] TSDB: Optimise seek within index. #14393
+* [ENHANCEMENT] TSDB: Optimise deletion of stale series. #14307
+* [ENHANCEMENT] TSDB: Reduce locking to optimise adding and removing series. #13286,#14286
+* [ENHANCEMENT] TSDB: Small optimisation: streamline special handling for out-of-order data. #14396,#14584
+* [ENHANCEMENT] Regexps: Optimize patterns with multiple prefixes. #13843,#14368
+* [ENHANCEMENT] Regexps: Optimize patterns containing multiple literal strings. #14173
+* [ENHANCEMENT] AWS SD: expose Primary IPv6 addresses as __meta_ec2_primary_ipv6_addresses. #14156
+* [ENHANCEMENT] Docker SD: add MatchFirstNetwork for containers with multiple networks. #10490
+* [ENHANCEMENT] OpenStack SD: Use `flavor.original_name` if available. #14312
+* [ENHANCEMENT] UI (experimental native histograms): more accurate representation. #13680,#14430
+* [ENHANCEMENT] Agent: `out_of_order_time_window` config option now applies to agent. #14094
+* [ENHANCEMENT] Notifier: Send any outstanding Alertmanager notifications when shutting down. #14290
+* [ENHANCEMENT] Rules: Add label-matcher support to Rules API. #10194
+* [ENHANCEMENT] HTTP API: Add url to message logged on error while sending response. #14209
+* [BUGFIX] TSDB: Exclude OOO chunks mapped after compaction starts (introduced by #14396). #14584
+* [BUGFIX] CLI: escape `|` characters when generating docs. #14420
+* [BUGFIX] PromQL (experimental native histograms): Fix some binary operators between native histogram values. #14454
+* [BUGFIX] TSDB: LabelNames API could fail during compaction. #14279
+* [BUGFIX] TSDB: Fix rare issue where pending OOO read can be left dangling if creating querier fails. #14341
+* [BUGFIX] TSDB: fix check for context cancellation in LabelNamesFor. #14302
+* [BUGFIX] Rules: Fix rare panic on reload. #14366
+* [BUGFIX] Config: In YAML marshalling, do not output a regexp field if it was never set. #14004
+* [BUGFIX] Remote-Write: reject samples with future timestamps. #14304
+* [BUGFIX] Remote-Write: Fix data corruption in remote write if max_sample_age is applied. #14078
+* [BUGFIX] Notifier: Fix Alertmanager discovery not updating under heavy load. #14174
+* [BUGFIX] Regexes: some Unicode characters were not matched by case-insensitive comparison. #14170,#14299
+* [BUGFIX] Remote-Read: Resolve occasional segmentation fault on query. #14515
 
 ## 2.53.1 / 2024-07-10
 

Makefile.common

@@ -61,7 +61,7 @@ PROMU_URL     := https://github.com/prometheus/promu/releases/download/v$(PROMU_
 SKIP_GOLANGCI_LINT :=
 GOLANGCI_LINT :=
 GOLANGCI_LINT_OPTS ?=
-GOLANGCI_LINT_VERSION ?= v1.59.1
+GOLANGCI_LINT_VERSION ?= v1.60.2
 # golangci-lint only supports linux, darwin and windows platforms on i386/amd64/arm64.
 # windows isn't included here because of the path separator being different.
 ifeq ($(GOHOSTOS),$(filter $(GOHOSTOS),linux darwin))

VERSION

@@ -1 +1 @@
-2.53.1
+2.54.1

cmd/prometheus/main.go

@@ -152,6 +152,7 @@ type flagConfig struct {
 	queryConcurrency    int
 	queryMaxSamples     int
 	RemoteFlushDeadline model.Duration
+	nameEscapingScheme  string
 
 	featureList   []string
 	memlimitRatio float64
@@ -168,6 +169,8 @@ type flagConfig struct {
 	corsRegexString string
 
 	promlogConfig promlog.Config
+
+	promqlEnableDelayedNameRemoval bool
 }
 
 // setFeatureListOptions sets the corresponding options from the featureList.
@@ -234,6 +237,15 @@ func (c *flagConfig) setFeatureListOptions(logger log.Logger) error {
 				config.DefaultConfig.GlobalConfig.ScrapeProtocols = config.DefaultProtoFirstScrapeProtocols
 				config.DefaultGlobalConfig.ScrapeProtocols = config.DefaultProtoFirstScrapeProtocols
 				level.Info(logger).Log("msg", "Experimental created timestamp zero ingestion enabled. Changed default scrape_protocols to prefer PrometheusProto format.", "global.scrape_protocols", fmt.Sprintf("%v", config.DefaultGlobalConfig.ScrapeProtocols))
+			case "delayed-compaction":
+				c.tsdb.EnableDelayedCompaction = true
+				level.Info(logger).Log("msg", "Experimental delayed compaction is enabled.")
+			case "promql-delayed-name-removal":
+				c.promqlEnableDelayedNameRemoval = true
+				level.Info(logger).Log("msg", "Experimental PromQL delayed name removal enabled.")
+			case "utf8-names":
+				model.NameValidationScheme = model.UTF8Validation
+				level.Info(logger).Log("msg", "Experimental UTF-8 support enabled")
 			case "":
 				continue
 			case "promql-at-modifier", "promql-negative-offset":
@@ -293,8 +305,8 @@ func main() {
 	a.Flag("config.file", "Prometheus configuration file path.").
 		Default("prometheus.yml").StringVar(&cfg.configFile)
 
-	a.Flag("web.listen-address", "Address to listen on for UI, API, and telemetry.").
+	a.Flag("web.listen-address", "Address to listen on for UI, API, and telemetry. Can be repeated.").
-		Default("0.0.0.0:9090").StringVar(&cfg.web.ListenAddress)
+		Default("0.0.0.0:9090").StringsVar(&cfg.web.ListenAddresses)
 
 	a.Flag("auto-gomemlimit.ratio", "The ratio of reserved GOMEMLIMIT memory to the detected maximum container or system memory").
 		Default("0.9").FloatVar(&cfg.memlimitRatio)
@@ -308,7 +320,7 @@ func main() {
 		"Maximum duration before timing out read of the request, and closing idle connections.").
 		Default("5m").SetValue(&cfg.webTimeout)
 
-	a.Flag("web.max-connections", "Maximum number of simultaneous connections.").
+	a.Flag("web.max-connections", "Maximum number of simultaneous connections across all listeners.").
 		Default("512").IntVar(&cfg.web.MaxConnections)
 
 	a.Flag("web.external-url",
@@ -384,6 +396,9 @@ func main() {
 	serverOnlyFlag(a, "storage.tsdb.allow-overlapping-blocks", "[DEPRECATED] This flag has no effect. Overlapping blocks are enabled by default now.").
 		Default("true").Hidden().BoolVar(&b)
 
+	serverOnlyFlag(a, "storage.tsdb.allow-overlapping-compaction", "Allow compaction of overlapping blocks. If set to false, TSDB stops vertical compaction and leaves overlapping blocks there. The use case is to let another component handle the compaction of overlapping blocks.").
+		Default("true").Hidden().BoolVar(&cfg.tsdb.EnableOverlappingCompaction)
+
 	serverOnlyFlag(a, "storage.tsdb.wal-compression", "Compress the tsdb WAL.").
 		Hidden().Default("true").BoolVar(&cfg.tsdb.WALCompression)
 
@@ -478,7 +493,9 @@ func main() {
 	a.Flag("scrape.discovery-reload-interval", "Interval used by scrape manager to throttle target groups updates.").
 		Hidden().Default("5s").SetValue(&cfg.scrape.DiscoveryReloadInterval)
 
-	a.Flag("enable-feature", "Comma separated feature names to enable. Valid options: agent, auto-gomemlimit, exemplar-storage, expand-external-labels, memory-snapshot-on-shutdown, promql-per-step-stats, promql-experimental-functions, remote-write-receiver (DEPRECATED), extra-scrape-metrics, new-service-discovery-manager, auto-gomaxprocs, no-default-scrape-port, native-histograms, otlp-write-receiver, created-timestamp-zero-ingestion, concurrent-rule-eval, new-ui. See https://prometheus.io/docs/prometheus/latest/feature_flags/ for more details.").
+	a.Flag("scrape.name-escaping-scheme", `Method for escaping legacy invalid names when sending to Prometheus that does not support UTF-8. Can be one of "values", "underscores", or "dots".`).Default(scrape.DefaultNameEscapingScheme.String()).StringVar(&cfg.nameEscapingScheme)
+
+	a.Flag("enable-feature", "Comma separated feature names to enable. Valid options: agent, auto-gomaxprocs, auto-gomemlimit, concurrent-rule-eval, created-timestamp-zero-ingestion, delayed-compaction, exemplar-storage, expand-external-labels, extra-scrape-metrics, memory-snapshot-on-shutdown, native-histograms, new-service-discovery-manager, new-ui, no-default-scrape-port, otlp-write-receiver, promql-experimental-functions, promql-delayed-name-removal, promql-per-step-stats, remote-write-receiver (DEPRECATED), utf8-names. See https://prometheus.io/docs/prometheus/latest/feature_flags/ for more details.").
 		Default("").StringsVar(&cfg.featureList)
 
 	promlogflag.AddFlags(a, &cfg.promlogConfig)
@@ -506,6 +523,15 @@ func main() {
 		os.Exit(1)
 	}
 
+	if cfg.nameEscapingScheme != "" {
+		scheme, err := model.ToEscapingScheme(cfg.nameEscapingScheme)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, `Invalid name escaping scheme: %q; Needs to be one of "values", "underscores", or "dots"`, cfg.nameEscapingScheme)
+			os.Exit(1)
+		}
+		model.NameEscapingScheme = scheme
+	}
+
 	if agentMode && len(serverOnlyFlags) > 0 {
 		fmt.Fprintf(os.Stderr, "The following flag(s) can not be used in agent mode: %q", serverOnlyFlags)
 		os.Exit(3)
@@ -526,7 +552,7 @@ func main() {
 		localStoragePath = cfg.agentStoragePath
 	}
 
-	cfg.web.ExternalURL, err = computeExternalURL(cfg.prometheusURL, cfg.web.ListenAddress)
+	cfg.web.ExternalURL, err = computeExternalURL(cfg.prometheusURL, cfg.web.ListenAddresses[0])
 	if err != nil {
 		fmt.Fprintln(os.Stderr, fmt.Errorf("parse external URL %q: %w", cfg.prometheusURL, err))
 		os.Exit(2)
@@ -784,6 +810,7 @@ func main() {
 			EnableAtModifier:         true,
 			EnableNegativeOffset:     true,
 			EnablePerStepStats:       cfg.enablePerStepStats,
+			EnableDelayedNameRemoval: cfg.promqlEnableDelayedNameRemoval,
 		}
 
 		queryEngine = promql.NewEngine(opts)
@@ -972,15 +999,21 @@ func main() {
 		})
 	}
 
-	listener, err := webHandler.Listener()
+	listeners, err := webHandler.Listeners()
 	if err != nil {
-		level.Error(logger).Log("msg", "Unable to start web listener", "err", err)
+		level.Error(logger).Log("msg", "Unable to start web listeners", "err", err)
+		if err := queryEngine.Close(); err != nil {
+			level.Warn(logger).Log("msg", "Closing query engine failed", "err", err)
+		}
 		os.Exit(1)
 	}
 
 	err = toolkit_web.Validate(*webConfig)
 	if err != nil {
 		level.Error(logger).Log("msg", "Unable to validate web configuration file", "err", err)
+		if err := queryEngine.Close(); err != nil {
+			level.Warn(logger).Log("msg", "Closing query engine failed", "err", err)
+		}
 		os.Exit(1)
 	}
 
@@ -1002,6 +1035,9 @@ func main() {
 				case <-cancel:
 					reloadReady.Close()
 				}
+				if err := queryEngine.Close(); err != nil {
+					level.Warn(logger).Log("msg", "Closing query engine failed", "err", err)
+				}
 				return nil
 			},
 			func(err error) {
@@ -1269,7 +1305,7 @@ func main() {
 		// Web handler.
 		g.Add(
 			func() error {
-				if err := webHandler.Run(ctxWeb, listener, *webConfig); err != nil {
+				if err := webHandler.Run(ctxWeb, listeners, *webConfig); err != nil {
 					return fmt.Errorf("error starting web server: %w", err)
 				}
 				return nil
@@ -1718,6 +1754,8 @@ type tsdbOptions struct {
 	MaxExemplars                   int64
 	EnableMemorySnapshotOnShutdown bool
 	EnableNativeHistograms         bool
+	EnableDelayedCompaction        bool
+	EnableOverlappingCompaction    bool
 }
 
 func (opts tsdbOptions) ToTSDBOptions() tsdb.Options {
@@ -1738,7 +1776,8 @@ func (opts tsdbOptions) ToTSDBOptions() tsdb.Options {
 		EnableMemorySnapshotOnShutdown: opts.EnableMemorySnapshotOnShutdown,
 		EnableNativeHistograms:         opts.EnableNativeHistograms,
 		OutOfOrderTimeWindow:           opts.OutOfOrderTimeWindow,
-		EnableOverlappingCompaction:    true,
+		EnableDelayedCompaction:        opts.EnableDelayedCompaction,
+		EnableOverlappingCompaction:    opts.EnableOverlappingCompaction,
 	}
 }
 

cmd/promtool/backfill.go

@@ -85,7 +85,7 @@ func getCompatibleBlockDuration(maxBlockDuration int64) int64 {
 	return blockDuration
 }
 
-func createBlocks(input []byte, mint, maxt, maxBlockDuration int64, maxSamplesInAppender int, outputDir string, humanReadable, quiet bool) (returnErr error) {
+func createBlocks(input []byte, mint, maxt, maxBlockDuration int64, maxSamplesInAppender int, outputDir string, humanReadable, quiet bool, customLabels map[string]string) (returnErr error) {
 	blockDuration := getCompatibleBlockDuration(maxBlockDuration)
 	mint = blockDuration * (mint / blockDuration)
 
@@ -102,6 +102,8 @@ func createBlocks(input []byte, mint, maxt, maxBlockDuration int64, maxSamplesIn
 		nextSampleTs int64 = math.MaxInt64
 	)
 
+	lb := labels.NewBuilder(labels.EmptyLabels())
+
 	for t := mint; t <= maxt; t += blockDuration {
 		tsUpper := t + blockDuration
 		if nextSampleTs != math.MaxInt64 && nextSampleTs >= tsUpper {
@@ -162,7 +164,13 @@ func createBlocks(input []byte, mint, maxt, maxBlockDuration int64, maxSamplesIn
 				l := labels.Labels{}
 				p.Metric(&l)
 
-				if _, err := app.Append(0, l, *ts, v); err != nil {
+				lb.Reset(l)
+				for name, value := range customLabels {
+					lb.Set(name, value)
+				}
+				lbls := lb.Labels()
+
+				if _, err := app.Append(0, lbls, *ts, v); err != nil {
 					return fmt.Errorf("add sample: %w", err)
 				}
 
@@ -221,13 +229,13 @@ func createBlocks(input []byte, mint, maxt, maxBlockDuration int64, maxSamplesIn
 	return nil
 }
 
-func backfill(maxSamplesInAppender int, input []byte, outputDir string, humanReadable, quiet bool, maxBlockDuration time.Duration) (err error) {
+func backfill(maxSamplesInAppender int, input []byte, outputDir string, humanReadable, quiet bool, maxBlockDuration time.Duration, customLabels map[string]string) (err error) {
 	p := textparse.NewOpenMetricsParser(input, nil) // Don't need a SymbolTable to get max and min timestamps.
 	maxt, mint, err := getMinAndMaxTimestamps(p)
 	if err != nil {
 		return fmt.Errorf("getting min and max timestamp: %w", err)
 	}
-	if err = createBlocks(input, mint, maxt, int64(maxBlockDuration/time.Millisecond), maxSamplesInAppender, outputDir, humanReadable, quiet); err != nil {
+	if err = createBlocks(input, mint, maxt, int64(maxBlockDuration/time.Millisecond), maxSamplesInAppender, outputDir, humanReadable, quiet, customLabels); err != nil {
 		return fmt.Errorf("block creation: %w", err)
 	}
 	return nil

cmd/promtool/backfill_test.go

@@ -92,6 +92,7 @@ func TestBackfill(t *testing.T) {
 		Description          string
 		MaxSamplesInAppender int
 		MaxBlockDuration     time.Duration
+		Labels               map[string]string
 		Expected             struct {
 			MinTime       int64
 			MaxTime       int64
@@ -636,6 +637,49 @@ http_requests_total{code="400"} 1024 7199
 				},
 			},
 		},
+		{
+			ToParse: `# HELP http_requests_total The total number of HTTP requests.
+# TYPE http_requests_total counter
+http_requests_total{code="200"} 1 1624463088.000
+http_requests_total{code="200"} 2 1629503088.000
+http_requests_total{code="200"} 3 1629863088.000
+# EOF
+`,
+			IsOk:                 true,
+			Description:          "Sample with external labels.",
+			MaxSamplesInAppender: 5000,
+			MaxBlockDuration:     2048 * time.Hour,
+			Labels:               map[string]string{"cluster_id": "123", "org_id": "999"},
+			Expected: struct {
+				MinTime       int64
+				MaxTime       int64
+				NumBlocks     int
+				BlockDuration int64
+				Samples       []backfillSample
+			}{
+				MinTime:       1624463088000,
+				MaxTime:       1629863088000,
+				NumBlocks:     2,
+				BlockDuration: int64(1458 * time.Hour / time.Millisecond),
+				Samples: []backfillSample{
+					{
+						Timestamp: 1624463088000,
+						Value:     1,
+						Labels:    labels.FromStrings("__name__", "http_requests_total", "code", "200", "cluster_id", "123", "org_id", "999"),
+					},
+					{
+						Timestamp: 1629503088000,
+						Value:     2,
+						Labels:    labels.FromStrings("__name__", "http_requests_total", "code", "200", "cluster_id", "123", "org_id", "999"),
+					},
+					{
+						Timestamp: 1629863088000,
+						Value:     3,
+						Labels:    labels.FromStrings("__name__", "http_requests_total", "code", "200", "cluster_id", "123", "org_id", "999"),
+					},
+				},
+			},
+		},
 		{
 			ToParse: `# HELP rpc_duration_seconds A summary of the RPC duration in seconds.
 # TYPE rpc_duration_seconds summary
@@ -689,7 +733,7 @@ after_eof 1 2
 
 			outputDir := t.TempDir()
 
-			err := backfill(test.MaxSamplesInAppender, []byte(test.ToParse), outputDir, false, false, test.MaxBlockDuration)
+			err := backfill(test.MaxSamplesInAppender, []byte(test.ToParse), outputDir, false, false, test.MaxBlockDuration, test.Labels)
 
 			if !test.IsOk {
 				require.Error(t, err, test.Description)

cmd/promtool/main.go

@@ -253,6 +253,7 @@ func main() {
 	importQuiet := importCmd.Flag("quiet", "Do not print created blocks.").Short('q').Bool()
 	maxBlockDuration := importCmd.Flag("max-block-duration", "Maximum duration created blocks may span. Anything less than 2h is ignored.").Hidden().PlaceHolder("<duration>").Duration()
 	openMetricsImportCmd := importCmd.Command("openmetrics", "Import samples from OpenMetrics input and produce TSDB blocks. Please refer to the storage docs for more details.")
+	openMetricsLabels := openMetricsImportCmd.Flag("label", "Label to attach to metrics. Can be specified multiple times. Example --label=label_name=label_value").StringMap()
 	importFilePath := openMetricsImportCmd.Arg("input file", "OpenMetrics file to read samples from.").Required().String()
 	importDBPath := openMetricsImportCmd.Arg("output directory", "Output directory for generated blocks.").Default(defaultDBPath).String()
 	importRulesCmd := importCmd.Command("rules", "Create blocks of data for new recording rules.")
@@ -408,7 +409,7 @@ func main() {
 		os.Exit(checkErr(dumpSamples(ctx, *dumpOpenMetricsPath, *dumpOpenMetricsSandboxDirRoot, *dumpOpenMetricsMinTime, *dumpOpenMetricsMaxTime, *dumpOpenMetricsMatch, formatSeriesSetOpenMetrics)))
 	// TODO(aSquare14): Work on adding support for custom block size.
 	case openMetricsImportCmd.FullCommand():
-		os.Exit(backfillOpenMetrics(*importFilePath, *importDBPath, *importHumanReadable, *importQuiet, *maxBlockDuration))
+		os.Exit(backfillOpenMetrics(*importFilePath, *importDBPath, *importHumanReadable, *importQuiet, *maxBlockDuration, *openMetricsLabels))
 
 	case importRulesCmd.FullCommand():
 		os.Exit(checkErr(importRules(serverURL, httpRoundTripper, *importRulesStart, *importRulesEnd, *importRulesOutputDir, *importRulesEvalInterval, *maxBlockDuration, *importRulesFiles...)))
@@ -471,7 +472,7 @@ func (ls lintConfig) lintDuplicateRules() bool {
 	return ls.all || ls.duplicateRules
 }
 
-// Check server status - healthy & ready.
+// CheckServerStatus - healthy & ready.
 func CheckServerStatus(serverURL *url.URL, checkEndpoint string, roundTripper http.RoundTripper) error {
 	if serverURL.Scheme == "" {
 		serverURL.Scheme = "http"

cmd/promtool/metrics.go

@@ -31,7 +31,7 @@ import (
 	"github.com/prometheus/prometheus/util/fmtutil"
 )
 
-// Push metrics to a prometheus remote write (for testing purpose only).
+// PushMetrics to a prometheus remote write (for testing purpose only).
 func PushMetrics(url *url.URL, roundTripper http.RoundTripper, headers map[string]string, timeout time.Duration, labels map[string]string, files ...string) int {
 	addressURL, err := url.Parse(url.String())
 	if err != nil {

cmd/promtool/tsdb.go

@@ -823,7 +823,7 @@ func checkErr(err error) int {
 	return 0
 }
 
-func backfillOpenMetrics(path, outputDir string, humanReadable, quiet bool, maxBlockDuration time.Duration) int {
+func backfillOpenMetrics(path, outputDir string, humanReadable, quiet bool, maxBlockDuration time.Duration, customLabels map[string]string) int {
 	inputFile, err := fileutil.OpenMmapFile(path)
 	if err != nil {
 		return checkErr(err)
@@ -834,7 +834,7 @@ func backfillOpenMetrics(path, outputDir string, humanReadable, quiet bool, maxB
 		return checkErr(fmt.Errorf("create output dir: %w", err))
 	}
 
-	return checkErr(backfill(5000, inputFile.Bytes(), outputDir, humanReadable, quiet, maxBlockDuration))
+	return checkErr(backfill(5000, inputFile.Bytes(), outputDir, humanReadable, quiet, maxBlockDuration, customLabels))
 }
 
 func displayHistogram(dataType string, datas []int, total int) {
@@ -866,16 +866,16 @@ func displayHistogram(dataType string, datas []int, total int) {
 	fmt.Println()
 }
 
-func generateBucket(min, max int) (start, end, step int) {
+func generateBucket(minVal, maxVal int) (start, end, step int) {
-	s := (max - min) / 10
+	s := (maxVal - minVal) / 10
 
 	step = 10
 	for step < s && step <= 10000 {
 		step *= 10
 	}
 
-	start = min - min%step
+	start = minVal - minVal%step
-	end = max - max%step + step
+	end = maxVal - maxVal%step + step
 
 	return
 }

cmd/promtool/tsdb_test.go

@@ -20,6 +20,7 @@ import (
 	"math"
 	"os"
 	"runtime"
+	"slices"
 	"strings"
 	"testing"
 	"time"
@@ -152,12 +153,18 @@ func TestTSDBDump(t *testing.T) {
 			expectedMetrics, err := os.ReadFile(tt.expectedDump)
 			require.NoError(t, err)
 			expectedMetrics = normalizeNewLine(expectedMetrics)
-			// even though in case of one matcher samples are not sorted, the order in the cases above should stay the same.
+			// Sort both, because Prometheus does not guarantee the output order.
-			require.Equal(t, string(expectedMetrics), dumpedMetrics)
+			require.Equal(t, sortLines(string(expectedMetrics)), sortLines(dumpedMetrics))
 		})
 	}
 }
 
+func sortLines(buf string) string {
+	lines := strings.Split(buf, "\n")
+	slices.Sort(lines)
+	return strings.Join(lines, "\n")
+}
+
 func TestTSDBDumpOpenMetrics(t *testing.T) {
 	storage := promqltest.LoadedStorage(t, `
 		load 1m
@@ -169,7 +176,7 @@ func TestTSDBDumpOpenMetrics(t *testing.T) {
 	require.NoError(t, err)
 	expectedMetrics = normalizeNewLine(expectedMetrics)
 	dumpedMetrics := getDumpedSamples(t, storage.Dir(), math.MinInt64, math.MaxInt64, []string{"{__name__=~'(?s:.*)'}"}, formatSeriesSetOpenMetrics)
-	require.Equal(t, string(expectedMetrics), dumpedMetrics)
+	require.Equal(t, sortLines(string(expectedMetrics)), sortLines(dumpedMetrics))
 }
 
 func TestTSDBDumpOpenMetricsRoundTrip(t *testing.T) {
@@ -179,7 +186,7 @@ func TestTSDBDumpOpenMetricsRoundTrip(t *testing.T) {
 
 	dbDir := t.TempDir()
 	// Import samples from OM format
-	err = backfill(5000, initialMetrics, dbDir, false, false, 2*time.Hour)
+	err = backfill(5000, initialMetrics, dbDir, false, false, 2*time.Hour, map[string]string{})
 	require.NoError(t, err)
 	db, err := tsdb.Open(dbDir, nil, nil, tsdb.DefaultOptions(), nil)
 	require.NoError(t, err)

config/config.go

@@ -67,6 +67,11 @@ var (
 	}
 )
 
+const (
+	LegacyValidationConfig = "legacy"
+	UTF8ValidationConfig   = "utf8"
+)
+
 // Load parses the YAML input s into a Config.
 func Load(s string, expandExternalLabels bool, logger log.Logger) (*Config, error) {
 	cfg := &Config{}
@@ -216,6 +221,7 @@ var (
 	// DefaultRemoteReadConfig is the default remote read configuration.
 	DefaultRemoteReadConfig = RemoteReadConfig{
 		RemoteTimeout:        model.Duration(1 * time.Minute),
+		ChunkedReadLimit:     DefaultChunkedReadLimit,
 		HTTPClientConfig:     config.DefaultHTTPClientConfig,
 		FilterExternalLabels: true,
 	}
@@ -446,6 +452,8 @@ type GlobalConfig struct {
 	// Keep no more than this many dropped targets per job.
 	// 0 means no limit.
 	KeepDroppedTargets uint `yaml:"keep_dropped_targets,omitempty"`
+	// Allow UTF8 Metric and Label Names.
+	MetricNameValidationScheme string `yaml:"metric_name_validation_scheme,omitempty"`
 }
 
 // ScrapeProtocol represents supported protocol for scraping metrics.
@@ -471,6 +479,7 @@ var (
 	PrometheusText0_0_4  ScrapeProtocol = "PrometheusText0.0.4"
 	OpenMetricsText0_0_1 ScrapeProtocol = "OpenMetricsText0.0.1"
 	OpenMetricsText1_0_0 ScrapeProtocol = "OpenMetricsText1.0.0"
+	UTF8NamesHeader      string         = model.EscapingKey + "=" + model.AllowUTF8
 
 	ScrapeProtocolsHeaders = map[ScrapeProtocol]string{
 		PrometheusProto:      "application/vnd.google.protobuf;proto=io.prometheus.client.MetricFamily;encoding=delimited",
@@ -656,6 +665,8 @@ type ScrapeConfig struct {
 	// Keep no more than this many dropped targets per job.
 	// 0 means no limit.
 	KeepDroppedTargets uint `yaml:"keep_dropped_targets,omitempty"`
+	// Allow UTF8 Metric and Label Names.
+	MetricNameValidationScheme string `yaml:"metric_name_validation_scheme,omitempty"`
 
 	// We cannot do proper Go type embedding below as the parser will then parse
 	// values arbitrarily into the overflow maps of further-down types.
@@ -762,6 +773,19 @@ func (c *ScrapeConfig) Validate(globalConfig GlobalConfig) error {
 		return fmt.Errorf("%w for scrape config with job name %q", err, c.JobName)
 	}
 
+	switch globalConfig.MetricNameValidationScheme {
+	case "", LegacyValidationConfig:
+	case UTF8ValidationConfig:
+		if model.NameValidationScheme != model.UTF8Validation {
+			return fmt.Errorf("utf8 name validation requested but feature not enabled via --enable-feature=utf8-names")
+		}
+	default:
+		return fmt.Errorf("unknown name validation method specified, must be either 'legacy' or 'utf8', got %s", globalConfig.MetricNameValidationScheme)
+	}
+	if c.MetricNameValidationScheme == "" {
+		c.MetricNameValidationScheme = globalConfig.MetricNameValidationScheme
+	}
+
 	return nil
 }
 
@@ -1090,8 +1114,9 @@ func (m RemoteWriteProtoMsgs) String() string {
 }
 
 var (
-	// RemoteWriteProtoMsgV1 represents the deprecated `prometheus.WriteRequest` protobuf
+	// RemoteWriteProtoMsgV1 represents the `prometheus.WriteRequest` protobuf
-	// message introduced in the https://prometheus.io/docs/specs/remote_write_spec/.
+	// message introduced in the https://prometheus.io/docs/specs/remote_write_spec/,
+	// which will eventually be deprecated.
 	//
 	// NOTE: This string is used for both HTTP header values and config value, so don't change
 	// this reference.
@@ -1255,10 +1280,17 @@ type MetadataConfig struct {
 	MaxSamplesPerSend int `yaml:"max_samples_per_send,omitempty"`
 }
 
+const (
+	// DefaultChunkedReadLimit is the default value for the maximum size of the protobuf frame client allows.
+	// 50MB is the default. This is equivalent to ~100k full XOR chunks and average labelset.
+	DefaultChunkedReadLimit = 5e+7
+)
+
 // RemoteReadConfig is the configuration for reading from remote storage.
 type RemoteReadConfig struct {
 	URL              *config.URL       `yaml:"url"`
 	RemoteTimeout    model.Duration    `yaml:"remote_timeout,omitempty"`
+	ChunkedReadLimit uint64            `yaml:"chunked_read_limit,omitempty"`
 	Headers          map[string]string `yaml:"headers,omitempty"`
 	ReadRecent       bool              `yaml:"read_recent,omitempty"`
 	Name             string            `yaml:"name,omitempty"`

config/config_test.go

@@ -16,6 +16,7 @@ package config
 import (
 	"crypto/tls"
 	"encoding/json"
+	"fmt"
 	"net/url"
 	"os"
 	"path/filepath"
@@ -166,6 +167,7 @@ var expectedConf = &Config{
 		{
 			URL:              mustParseURL("http://remote1/read"),
 			RemoteTimeout:    model.Duration(1 * time.Minute),
+			ChunkedReadLimit: DefaultChunkedReadLimit,
 			ReadRecent:       true,
 			Name:             "default",
 			HTTPClientConfig: config.HTTPClientConfig{
@@ -177,6 +179,7 @@ var expectedConf = &Config{
 		{
 			URL:              mustParseURL("http://remote3/read"),
 			RemoteTimeout:    model.Duration(1 * time.Minute),
+			ChunkedReadLimit: DefaultChunkedReadLimit,
 			ReadRecent:       false,
 			Name:             "read_special",
 			RequiredMatchers: model.LabelSet{"job": "special"},
@@ -2300,3 +2303,52 @@ func TestScrapeConfigDisableCompression(t *testing.T) {
 
 	require.False(t, got.ScrapeConfigs[0].EnableCompression)
 }
+
+func TestScrapeConfigNameValidationSettings(t *testing.T) {
+	model.NameValidationScheme = model.UTF8Validation
+	defer func() {
+		model.NameValidationScheme = model.LegacyValidation
+	}()
+
+	tests := []struct {
+		name         string
+		inputFile    string
+		expectScheme string
+	}{
+		{
+			name:         "blank config implies default",
+			inputFile:    "scrape_config_default_validation_mode",
+			expectScheme: "",
+		},
+		{
+			name:         "global setting implies local settings",
+			inputFile:    "scrape_config_global_validation_mode",
+			expectScheme: "utf8",
+		},
+		{
+			name:         "local setting",
+			inputFile:    "scrape_config_local_validation_mode",
+			expectScheme: "utf8",
+		},
+		{
+			name:         "local setting overrides global setting",
+			inputFile:    "scrape_config_local_global_validation_mode",
+			expectScheme: "legacy",
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			want, err := LoadFile(fmt.Sprintf("testdata/%s.yml", tc.inputFile), false, false, log.NewNopLogger())
+			require.NoError(t, err)
+
+			out, err := yaml.Marshal(want)
+
+			require.NoError(t, err)
+			got := &Config{}
+			require.NoError(t, yaml.UnmarshalStrict(out, got))
+
+			require.Equal(t, tc.expectScheme, got.ScrapeConfigs[0].MetricNameValidationScheme)
+		})
+	}
+}

config/testdata/scrape_config_default_validation_mode.yml

@@ -0,0 +1,2 @@
+scrape_configs:
+  - job_name: prometheus

config/testdata/scrape_config_global_validation_mode.yml

@@ -0,0 +1,4 @@
+global:
+  metric_name_validation_scheme: utf8
+scrape_configs:
+  - job_name: prometheus

config/testdata/scrape_config_local_global_validation_mode.yml

@@ -0,0 +1,5 @@
+global:
+  metric_name_validation_scheme: utf8
+scrape_configs:
+  - job_name: prometheus
+    metric_name_validation_scheme: legacy

config/testdata/scrape_config_local_validation_mode.yml

@@ -0,0 +1,3 @@
+scrape_configs:
+  - job_name: prometheus
+    metric_name_validation_scheme: utf8

discovery/discoverer_metrics_noop.go

@@ -13,7 +13,7 @@
 
 package discovery
 
-// Create a dummy metrics struct, because this SD doesn't have any metrics.
+// NoopDiscovererMetrics creates a dummy metrics struct, because this SD doesn't have any metrics.
 type NoopDiscovererMetrics struct{}
 
 var _ DiscovererMetrics = (*NoopDiscovererMetrics)(nil)

discovery/discovery.go

@@ -39,7 +39,7 @@ type Discoverer interface {
 	Run(ctx context.Context, up chan<- []*targetgroup.Group)
 }
 
-// Internal metrics of service discovery mechanisms.
+// DiscovererMetrics are internal metrics of service discovery mechanisms.
 type DiscovererMetrics interface {
 	Register() error
 	Unregister()
@@ -56,7 +56,7 @@ type DiscovererOptions struct {
 	HTTPClientOptions []config.HTTPClientOption
 }
 
-// Metrics used by the "refresh" package.
+// RefreshMetrics are used by the "refresh" package.
 // We define them here in the "discovery" package in order to avoid a cyclic dependency between
 // "discovery" and "refresh".
 type RefreshMetrics struct {
@@ -64,17 +64,18 @@ type RefreshMetrics struct {
 	Duration prometheus.Observer
 }
 
-// Instantiate the metrics used by the "refresh" package.
+// RefreshMetricsInstantiator instantiates the metrics used by the "refresh" package.
 type RefreshMetricsInstantiator interface {
 	Instantiate(mech string) *RefreshMetrics
 }
 
-// An interface for registering, unregistering, and instantiating metrics for the "refresh" package.
+// RefreshMetricsManager is an interface for registering, unregistering, and
-// Refresh metrics are registered and unregistered outside of the service discovery mechanism.
+// instantiating metrics for the "refresh" package. Refresh metrics are
-// This is so that the same metrics can be reused across different service discovery mechanisms.
+// registered and unregistered outside of the service discovery mechanism. This
-// To manage refresh metrics inside the SD mechanism, we'd need to use const labels which are
+// is so that the same metrics can be reused across different service discovery
-// specific to that SD. However, doing so would also expose too many unused metrics on
+// mechanisms. To manage refresh metrics inside the SD mechanism, we'd need to
-// the Prometheus /metrics endpoint.
+// use const labels which are specific to that SD. However, doing so would also
+// expose too many unused metrics on the Prometheus /metrics endpoint.
 type RefreshMetricsManager interface {
 	DiscovererMetrics
 	RefreshMetricsInstantiator
@@ -145,7 +146,8 @@ func (c StaticConfig) NewDiscoverer(DiscovererOptions) (Discoverer, error) {
 	return staticDiscoverer(c), nil
 }
 
-// No metrics are needed for this service discovery mechanism.
+// NewDiscovererMetrics returns NoopDiscovererMetrics because no metrics are
+// needed for this service discovery mechanism.
 func (c StaticConfig) NewDiscovererMetrics(prometheus.Registerer, RefreshMetricsInstantiator) DiscovererMetrics {
 	return &NoopDiscovererMetrics{}
 }

discovery/eureka/client.go

@@ -97,7 +97,6 @@ func fetchApps(ctx context.Context, server string, client *http.Client) (*Applic
 		resp.Body.Close()
 	}()
 
-	//nolint:usestdlibvars
 	if resp.StatusCode/100 != 2 {
 		return nil, fmt.Errorf("non 2xx status '%d' response during eureka service discovery", resp.StatusCode)
 	}

discovery/hetzner/robot.go

@@ -87,7 +87,6 @@ func (d *robotDiscovery) refresh(context.Context) ([]*targetgroup.Group, error)
 		resp.Body.Close()
 	}()
 
-	//nolint:usestdlibvars
 	if resp.StatusCode/100 != 2 {
 		return nil, fmt.Errorf("non 2xx status '%d' response during hetzner service discovery with role robot", resp.StatusCode)
 	}

discovery/kubernetes/endpoints_test.go

@@ -970,7 +970,7 @@ func TestEndpointsDiscoveryEmptyPodStatus(t *testing.T) {
 	}.Run(t)
 }
 
-// TestEndpointsUpdatePod makes sure that Endpoints discovery detects underlying Pods changes.
+// TestEndpointsDiscoveryUpdatePod makes sure that Endpoints discovery detects underlying Pods changes.
 // See https://github.com/prometheus/prometheus/issues/11305 for more details.
 func TestEndpointsDiscoveryUpdatePod(t *testing.T) {
 	pod := &v1.Pod{

discovery/kubernetes/kubernetes_test.go

@@ -154,7 +154,7 @@ func (d k8sDiscoveryTest) Run(t *testing.T) {
 
 // readResultWithTimeout reads all targetgroups from channel with timeout.
 // It merges targetgroups by source and sends the result to result channel.
-func readResultWithTimeout(t *testing.T, ctx context.Context, ch <-chan []*targetgroup.Group, max int, stopAfter time.Duration, resChan chan<- map[string]*targetgroup.Group) {
+func readResultWithTimeout(t *testing.T, ctx context.Context, ch <-chan []*targetgroup.Group, maxGroups int, stopAfter time.Duration, resChan chan<- map[string]*targetgroup.Group) {
 	res := make(map[string]*targetgroup.Group)
 	timeout := time.After(stopAfter)
 Loop:
@@ -167,7 +167,7 @@ Loop:
 				}
 				res[tg.Source] = tg
 			}
-			if len(res) == max {
+			if len(res) == maxGroups {
 				// Reached max target groups we may get, break fast.
 				break Loop
 			}
@@ -175,10 +175,10 @@ Loop:
 			// Because we use queue, an object that is created then
 			// deleted or updated may be processed only once.
 			// So possibly we may skip events, timed out here.
-			t.Logf("timed out, got %d (max: %d) items, some events are skipped", len(res), max)
+			t.Logf("timed out, got %d (max: %d) items, some events are skipped", len(res), maxGroups)
 			break Loop
 		case <-ctx.Done():
-			t.Logf("stopped, got %d (max: %d) items", len(res), max)
+			t.Logf("stopped, got %d (max: %d) items", len(res), maxGroups)
 			break Loop
 		}
 	}

discovery/manager.go

@@ -64,7 +64,7 @@ func (p *Provider) Config() interface{} {
 	return p.config
 }
 
-// Registers the metrics needed for SD mechanisms.
+// CreateAndRegisterSDMetrics registers the metrics needed for SD mechanisms.
 // Does not register the metrics for the Discovery Manager.
 // TODO(ptodev): Add ability to unregister the metrics?
 func CreateAndRegisterSDMetrics(reg prometheus.Registerer) (map[string]DiscovererMetrics, error) {
@@ -213,8 +213,6 @@ func (m *Manager) ApplyConfig(cfg map[string]Configs) error {
 
 	var (
 		wg           sync.WaitGroup
-		// keep shows if we keep any providers after reload.
-		keep         bool
 		newProviders []*Provider
 	)
 	for _, prov := range m.providers {
@@ -228,13 +226,12 @@ func (m *Manager) ApplyConfig(cfg map[string]Configs) error {
 			continue
 		}
 		newProviders = append(newProviders, prov)
-		// refTargets keeps reference targets used to populate new subs' targets
+		// refTargets keeps reference targets used to populate new subs' targets as they should be the same.
 		var refTargets map[string]*targetgroup.Group
 		prov.mu.Lock()
 
 		m.targetsMtx.Lock()
 		for s := range prov.subs {
-			keep = true
 			refTargets = m.targets[poolKey{s, prov.name}]
 			// Remove obsolete subs' targets.
 			if _, ok := prov.newSubs[s]; !ok {
@@ -267,7 +264,9 @@ func (m *Manager) ApplyConfig(cfg map[string]Configs) error {
 	// While startProvider does pull the trigger, it may take some time to do so, therefore
 	// we pull the trigger as soon as possible so that downstream managers can populate their state.
 	// See https://github.com/prometheus/prometheus/pull/8639 for details.
-	if keep {
+	// This also helps making the downstream managers drop stale targets as soon as possible.
+	// See https://github.com/prometheus/prometheus/pull/13147 for details.
+	if len(m.providers) > 0 {
 		select {
 		case m.triggerSend <- struct{}{}:
 		default:
@@ -288,7 +287,9 @@ func (m *Manager) StartCustomProvider(ctx context.Context, name string, worker D
 			name: {},
 		},
 	}
+	m.mtx.Lock()
 	m.providers = append(m.providers, p)
+	m.mtx.Unlock()
 	m.startProvider(ctx, p)
 }
 
@@ -393,8 +394,16 @@ func (m *Manager) updateGroup(poolKey poolKey, tgs []*targetgroup.Group) {
 		m.targets[poolKey] = make(map[string]*targetgroup.Group)
 	}
 	for _, tg := range tgs {
-		if tg != nil { // Some Discoverers send nil target group so need to check for it to avoid panics.
+		// Some Discoverers send nil target group so need to check for it to avoid panics.
+		if tg == nil {
+			continue
+		}
+		if len(tg.Targets) > 0 {
 			m.targets[poolKey][tg.Source] = tg
+		} else {
+			// The target group is empty, drop the corresponding entry to avoid leaks.
+			// In case the group yielded targets before, allGroups() will take care of making consumers drop them.
+			delete(m.targets[poolKey], tg.Source)
 		}
 	}
 }
@@ -403,19 +412,33 @@ func (m *Manager) allGroups() map[string][]*targetgroup.Group {
 	tSets := map[string][]*targetgroup.Group{}
 	n := map[string]int{}
 
+	m.mtx.RLock()
 	m.targetsMtx.Lock()
-	defer m.targetsMtx.Unlock()
+	for _, p := range m.providers {
-	for pkey, tsets := range m.targets {
+		p.mu.RLock()
+		for s := range p.subs {
+			// Send empty lists for subs without any targets to make sure old stale targets are dropped by consumers.
+			// See: https://github.com/prometheus/prometheus/issues/12858 for details.
+			if _, ok := tSets[s]; !ok {
+				tSets[s] = []*targetgroup.Group{}
+				n[s] = 0
+			}
+			if tsets, ok := m.targets[poolKey{s, p.name}]; ok {
 				for _, tg := range tsets {
-			// Even if the target group 'tg' is empty we still need to send it to the 'Scrape manager'
+					tSets[s] = append(tSets[s], tg)
-			// to signal that it needs to stop all scrape loops for this target set.
+					n[s] += len(tg.Targets)
-			tSets[pkey.setName] = append(tSets[pkey.setName], tg)
-			n[pkey.setName] += len(tg.Targets)
 				}
 			}
+		}
+		p.mu.RUnlock()
+	}
+	m.targetsMtx.Unlock()
+	m.mtx.RUnlock()
+
 	for setName, v := range n {
 		m.metrics.DiscoveredTargets.WithLabelValues(setName).Set(float64(v))
 	}
+
 	return tSets
 }
 

discovery/manager_test.go

@@ -939,11 +939,13 @@ func TestTargetSetTargetGroupsPresentOnConfigChange(t *testing.T) {
 	discoveryManager.ApplyConfig(c)
 
 	// Original targets should be present as soon as possible.
+	// An empty list should be sent for prometheus2 to drop any stale targets
 	syncedTargets = <-discoveryManager.SyncCh()
 	mu.Unlock()
-	require.Len(t, syncedTargets, 1)
+	require.Len(t, syncedTargets, 2)
 	verifySyncedPresence(t, syncedTargets, "prometheus", "{__address__=\"foo:9090\"}", true)
 	require.Len(t, syncedTargets["prometheus"], 1)
+	require.Empty(t, syncedTargets["prometheus2"])
 
 	// prometheus2 configs should be ready on second sync.
 	syncedTargets = <-discoveryManager.SyncCh()
@@ -1049,8 +1051,8 @@ func TestDiscovererConfigs(t *testing.T) {
 }
 
 // TestTargetSetRecreatesEmptyStaticConfigs ensures that reloading a config file after
-// removing all targets from the static_configs sends an update with empty targetGroups.
+// removing all targets from the static_configs cleans the corresponding targetGroups entries to avoid leaks and sends an empty update.
-// This is required to signal the receiver that this target set has no current targets.
+// The update is required to signal the consumers that the previous targets should be dropped.
 func TestTargetSetRecreatesEmptyStaticConfigs(t *testing.T) {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
@@ -1083,16 +1085,14 @@ func TestTargetSetRecreatesEmptyStaticConfigs(t *testing.T) {
 	discoveryManager.ApplyConfig(c)
 
 	syncedTargets = <-discoveryManager.SyncCh()
+	require.Len(t, discoveryManager.targets, 1)
 	p = pk("static", "prometheus", 1)
 	targetGroups, ok := discoveryManager.targets[p]
-	require.True(t, ok, "'%v' should be present in target groups", p)
+	require.True(t, ok, "'%v' should be present in targets", p)
-	group, ok := targetGroups[""]
+	// Otherwise the targetGroups will leak, see https://github.com/prometheus/prometheus/issues/12436.
-	require.True(t, ok, "missing '' key in target groups %v", targetGroups)
+	require.Empty(t, targetGroups, 0, "'%v' should no longer have any associated target groups", p)
-
+	require.Len(t, syncedTargets, 1, "an update with no targetGroups should still be sent.")
-	require.Empty(t, group.Targets, "Invalid number of targets.")
+	require.Empty(t, syncedTargets["prometheus"], 0)
-	require.Len(t, syncedTargets, 1)
-	require.Len(t, syncedTargets["prometheus"], 1)
-	require.Nil(t, syncedTargets["prometheus"][0].Labels)
 }
 
 func TestIdenticalConfigurationsAreCoalesced(t *testing.T) {
@@ -1275,6 +1275,7 @@ func TestCoordinationWithReceiver(t *testing.T) {
 								Targets: []model.LabelSet{{"__instance__": "1"}},
 							},
 						},
+						"mock1": {},
 					},
 				},
 				{

discovery/metrics_refresh.go

@@ -17,7 +17,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 )
 
-// Metric vectors for the "refresh" package.
+// RefreshMetricsVecs are metric vectors for the "refresh" package.
 // We define them here in the "discovery" package in order to avoid a cyclic dependency between
 // "discovery" and "refresh".
 type RefreshMetricsVecs struct {

discovery/moby/docker.go

@@ -19,6 +19,7 @@ import (
 	"net"
 	"net/http"
 	"net/url"
+	"sort"
 	"strconv"
 	"time"
 
@@ -251,28 +252,26 @@ func (d *DockerDiscovery) refresh(ctx context.Context) ([]*targetgroup.Group, er
 		}
 
 		if d.matchFirstNetwork && len(networks) > 1 {
-			// Match user defined network
+			// Sort networks by name and take first non-nil network.
-			if containerNetworkMode.IsUserDefined() {
+			keys := make([]string, 0, len(networks))
-				networkMode := string(containerNetworkMode)
-				networks = map[string]*network.EndpointSettings{networkMode: networks[networkMode]}
-			} else {
-				// Get first network if container network mode has "none" value.
-				// This case appears under certain condition:
-				// 1. Container created with network set to "--net=none".
-				// 2. Disconnect network "none".
-				// 3. Reconnect network with user defined networks.
-				var first string
 			for k, n := range networks {
 				if n != nil {
-						first = k
+					keys = append(keys, k)
-						break
 				}
 			}
-				networks = map[string]*network.EndpointSettings{first: networks[first]}
+			if len(keys) > 0 {
+				sort.Strings(keys)
+				firstNetworkMode := keys[0]
+				firstNetwork := networks[firstNetworkMode]
+				networks = map[string]*network.EndpointSettings{firstNetworkMode: firstNetwork}
 			}
 		}
 
 		for _, n := range networks {
+			if n == nil {
+				continue
+			}
+
 			var added bool
 
 			for _, p := range c.Ports {

discovery/moby/docker_test.go

@@ -60,9 +60,9 @@ host: %s
 	tg := tgs[0]
 	require.NotNil(t, tg)
 	require.NotNil(t, tg.Targets)
-	require.Len(t, tg.Targets, 6)
+	require.Len(t, tg.Targets, 8)
 
-	for i, lbls := range []model.LabelSet{
+	expected := []model.LabelSet{
 		{
 			"__address__":                "172.19.0.2:9100",
 			"__meta_docker_container_id": "c301b928faceb1a18fe379f6bc178727ef920bb30b0f9b8592b32b36255a0eca",
@@ -163,7 +163,43 @@ host: %s
 			"__meta_docker_network_scope":                              "local",
 			"__meta_docker_port_private":                               "9104",
 		},
-	} {
+		{
+			"__address__":                "172.20.0.3:3306",
+			"__meta_docker_container_id": "f84b2a0cfaa58d9e70b0657e2b3c6f44f0e973de4163a871299b4acf127b224f",
+			"__meta_docker_container_label_com_docker_compose_project": "dockersd",
+			"__meta_docker_container_label_com_docker_compose_service": "mysql",
+			"__meta_docker_container_label_com_docker_compose_version": "2.2.2",
+			"__meta_docker_container_name":                             "/dockersd_multi_networks",
+			"__meta_docker_container_network_mode":                     "dockersd_private_none",
+			"__meta_docker_network_id":                                 "e804771e55254a360fdb70dfdd78d3610fdde231b14ef2f837a00ac1eeb9e601",
+			"__meta_docker_network_ingress":                            "false",
+			"__meta_docker_network_internal":                           "false",
+			"__meta_docker_network_ip":                                 "172.20.0.3",
+			"__meta_docker_network_name":                               "dockersd_private",
+			"__meta_docker_network_scope":                              "local",
+			"__meta_docker_port_private":                               "3306",
+		},
+		{
+			"__address__":                "172.20.0.3:33060",
+			"__meta_docker_container_id": "f84b2a0cfaa58d9e70b0657e2b3c6f44f0e973de4163a871299b4acf127b224f",
+			"__meta_docker_container_label_com_docker_compose_project": "dockersd",
+			"__meta_docker_container_label_com_docker_compose_service": "mysql",
+			"__meta_docker_container_label_com_docker_compose_version": "2.2.2",
+			"__meta_docker_container_name":                             "/dockersd_multi_networks",
+			"__meta_docker_container_network_mode":                     "dockersd_private_none",
+			"__meta_docker_network_id":                                 "e804771e55254a360fdb70dfdd78d3610fdde231b14ef2f837a00ac1eeb9e601",
+			"__meta_docker_network_ingress":                            "false",
+			"__meta_docker_network_internal":                           "false",
+			"__meta_docker_network_ip":                                 "172.20.0.3",
+			"__meta_docker_network_name":                               "dockersd_private",
+			"__meta_docker_network_scope":                              "local",
+			"__meta_docker_port_private":                               "33060",
+		},
+	}
+	sortFunc(expected)
+	sortFunc(tg.Targets)
+
+	for i, lbls := range expected {
 		t.Run(fmt.Sprintf("item %d", i), func(t *testing.T) {
 			require.Equal(t, lbls, tg.Targets[i])
 		})
@@ -202,13 +238,8 @@ host: %s
 	tg := tgs[0]
 	require.NotNil(t, tg)
 	require.NotNil(t, tg.Targets)
-	require.Len(t, tg.Targets, 9)
+	require.Len(t, tg.Targets, 13)
 
-	sortFunc := func(labelSets []model.LabelSet) {
-		sort.Slice(labelSets, func(i, j int) bool {
-			return labelSets[i]["__address__"] < labelSets[j]["__address__"]
-		})
-	}
 	expected := []model.LabelSet{
 		{
 			"__address__":                "172.19.0.2:9100",
@@ -359,6 +390,70 @@ host: %s
 			"__meta_docker_network_scope":                              "local",
 			"__meta_docker_port_private":                               "9104",
 		},
+		{
+			"__address__":                "172.20.0.3:3306",
+			"__meta_docker_container_id": "f84b2a0cfaa58d9e70b0657e2b3c6f44f0e973de4163a871299b4acf127b224f",
+			"__meta_docker_container_label_com_docker_compose_project": "dockersd",
+			"__meta_docker_container_label_com_docker_compose_service": "mysql",
+			"__meta_docker_container_label_com_docker_compose_version": "2.2.2",
+			"__meta_docker_container_name":                             "/dockersd_multi_networks",
+			"__meta_docker_container_network_mode":                     "dockersd_private_none",
+			"__meta_docker_network_id":                                 "e804771e55254a360fdb70dfdd78d3610fdde231b14ef2f837a00ac1eeb9e601",
+			"__meta_docker_network_ingress":                            "false",
+			"__meta_docker_network_internal":                           "false",
+			"__meta_docker_network_ip":                                 "172.20.0.3",
+			"__meta_docker_network_name":                               "dockersd_private",
+			"__meta_docker_network_scope":                              "local",
+			"__meta_docker_port_private":                               "3306",
+		},
+		{
+			"__address__":                "172.20.0.3:33060",
+			"__meta_docker_container_id": "f84b2a0cfaa58d9e70b0657e2b3c6f44f0e973de4163a871299b4acf127b224f",
+			"__meta_docker_container_label_com_docker_compose_project": "dockersd",
+			"__meta_docker_container_label_com_docker_compose_service": "mysql",
+			"__meta_docker_container_label_com_docker_compose_version": "2.2.2",
+			"__meta_docker_container_name":                             "/dockersd_multi_networks",
+			"__meta_docker_container_network_mode":                     "dockersd_private_none",
+			"__meta_docker_network_id":                                 "e804771e55254a360fdb70dfdd78d3610fdde231b14ef2f837a00ac1eeb9e601",
+			"__meta_docker_network_ingress":                            "false",
+			"__meta_docker_network_internal":                           "false",
+			"__meta_docker_network_ip":                                 "172.20.0.3",
+			"__meta_docker_network_name":                               "dockersd_private",
+			"__meta_docker_network_scope":                              "local",
+			"__meta_docker_port_private":                               "33060",
+		},
+		{
+			"__address__":                "172.21.0.3:3306",
+			"__meta_docker_container_id": "f84b2a0cfaa58d9e70b0657e2b3c6f44f0e973de4163a871299b4acf127b224f",
+			"__meta_docker_container_label_com_docker_compose_project": "dockersd",
+			"__meta_docker_container_label_com_docker_compose_service": "mysql",
+			"__meta_docker_container_label_com_docker_compose_version": "2.2.2",
+			"__meta_docker_container_name":                             "/dockersd_multi_networks",
+			"__meta_docker_container_network_mode":                     "dockersd_private_none",
+			"__meta_docker_network_id":                                 "bfcf66a6b64f7d518f009e34290dc3f3c66a08164257ad1afc3bd31d75f656e8",
+			"__meta_docker_network_ingress":                            "false",
+			"__meta_docker_network_internal":                           "false",
+			"__meta_docker_network_ip":                                 "172.21.0.3",
+			"__meta_docker_network_name":                               "dockersd_private1",
+			"__meta_docker_network_scope":                              "local",
+			"__meta_docker_port_private":                               "3306",
+		},
+		{
+			"__address__":                "172.21.0.3:33060",
+			"__meta_docker_container_id": "f84b2a0cfaa58d9e70b0657e2b3c6f44f0e973de4163a871299b4acf127b224f",
+			"__meta_docker_container_label_com_docker_compose_project": "dockersd",
+			"__meta_docker_container_label_com_docker_compose_service": "mysql",
+			"__meta_docker_container_label_com_docker_compose_version": "2.2.2",
+			"__meta_docker_container_name":                             "/dockersd_multi_networks",
+			"__meta_docker_container_network_mode":                     "dockersd_private_none",
+			"__meta_docker_network_id":                                 "bfcf66a6b64f7d518f009e34290dc3f3c66a08164257ad1afc3bd31d75f656e8",
+			"__meta_docker_network_ingress":                            "false",
+			"__meta_docker_network_internal":                           "false",
+			"__meta_docker_network_ip":                                 "172.21.0.3",
+			"__meta_docker_network_name":                               "dockersd_private1",
+			"__meta_docker_network_scope":                              "local",
+			"__meta_docker_port_private":                               "33060",
+		},
 	}
 
 	sortFunc(expected)
@@ -370,3 +465,9 @@ host: %s
 		})
 	}
 }
+
+func sortFunc(labelSets []model.LabelSet) {
+	sort.Slice(labelSets, func(i, j int) bool {
+		return labelSets[i]["__address__"] < labelSets[j]["__address__"]
+	})
+}

discovery/moby/testdata/dockerprom/containers/json.json

@@ -228,5 +228,74 @@
       "Networks": {}
     },
     "Mounts": []
+  },
+  {
+    "Id": "f84b2a0cfaa58d9e70b0657e2b3c6f44f0e973de4163a871299b4acf127b224f",
+    "Names": [
+      "/dockersd_multi_networks"
+    ],
+    "Image": "mysql:5.7.29",
+    "ImageID": "sha256:16ae2f4625ba63a250462bedeece422e741de9f0caf3b1d89fd5b257aca80cd1",
+    "Command": "mysqld",
+    "Created": 1616273136,
+    "Ports": [
+      {
+        "PrivatePort": 3306,
+        "Type": "tcp"
+      },
+      {
+        "PrivatePort": 33060,
+        "Type": "tcp"
+      }
+    ],
+    "Labels": {
+      "com.docker.compose.project": "dockersd",
+      "com.docker.compose.service": "mysql",
+      "com.docker.compose.version": "2.2.2"
+    },
+    "State": "running",
+    "Status": "Up 40 seconds",
+    "HostConfig": {
+      "NetworkMode": "dockersd_private_none"
+    },
+    "NetworkSettings": {
+      "Networks": {
+        "dockersd_private": {
+          "IPAMConfig": null,
+          "Links": null,
+          "Aliases": null,
+          "NetworkID": "e804771e55254a360fdb70dfdd78d3610fdde231b14ef2f837a00ac1eeb9e601",
+          "EndpointID": "972d6807997369605ace863af58de6cb90c787a5bf2ffc4105662d393ae539b7",
+          "Gateway": "172.20.0.1",
+          "IPAddress": "172.20.0.3",
+          "IPPrefixLen": 16,
+          "IPv6Gateway": "",
+          "GlobalIPv6Address": "",
+          "GlobalIPv6PrefixLen": 0,
+          "MacAddress": "02:42:ac:14:00:02",
+          "DriverOpts": null
+        },
+        "dockersd_private1": {
+          "IPAMConfig": {},
+          "Links": null,
+          "Aliases": [
+            "mysql",
+            "mysql",
+            "f9ade4b83199"
+          ],
+          "NetworkID": "bfcf66a6b64f7d518f009e34290dc3f3c66a08164257ad1afc3bd31d75f656e8",
+          "EndpointID": "91a98405344ee1cb7d977cafabe634837876651544b32da20a5e0155868e6f5f",
+          "Gateway": "172.21.0.1",
+          "IPAddress": "172.21.0.3",
+          "IPPrefixLen": 24,
+          "IPv6Gateway": "",
+          "GlobalIPv6Address": "",
+          "GlobalIPv6PrefixLen": 0,
+          "MacAddress": "02:42:ac:15:00:02",
+          "DriverOpts": null
+        }
+      }
+    },
+    "Mounts": []
   }
 ]

discovery/util.go

@@ -19,8 +19,8 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 )
 
-// A utility to be used by implementations of discovery.Discoverer
+// MetricRegisterer is used by implementations of discovery.Discoverer that need
-// which need to manage the lifetime of their metrics.
+// to manage the lifetime of their metrics.
 type MetricRegisterer interface {
 	RegisterMetrics() error
 	UnregisterMetrics()
@@ -34,7 +34,7 @@ type metricRegistererImpl struct {
 
 var _ MetricRegisterer = &metricRegistererImpl{}
 
-// Creates an instance of a MetricRegisterer.
+// NewMetricRegisterer creates an instance of a MetricRegisterer.
 // Typically called inside the implementation of the NewDiscoverer() method.
 func NewMetricRegisterer(reg prometheus.Registerer, metrics []prometheus.Collector) MetricRegisterer {
 	return &metricRegistererImpl{

docs/command-line/prometheus.md

@@ -15,11 +15,11 @@ The Prometheus monitoring server
 | <code class="text-nowrap">-h</code>, <code class="text-nowrap">--help</code> | Show context-sensitive help (also try --help-long and --help-man). |  |
 | <code class="text-nowrap">--version</code> | Show application version. |  |
 | <code class="text-nowrap">--config.file</code> | Prometheus configuration file path. | `prometheus.yml` |
-| <code class="text-nowrap">--web.listen-address</code> | Address to listen on for UI, API, and telemetry. | `0.0.0.0:9090` |
+| <code class="text-nowrap">--web.listen-address</code> <code class="text-nowrap">...<code class="text-nowrap"> | Address to listen on for UI, API, and telemetry. Can be repeated. | `0.0.0.0:9090` |
 | <code class="text-nowrap">--auto-gomemlimit.ratio</code> | The ratio of reserved GOMEMLIMIT memory to the detected maximum container or system memory | `0.9` |
 | <code class="text-nowrap">--web.config.file</code> | [EXPERIMENTAL] Path to configuration file that can enable TLS or authentication. |  |
 | <code class="text-nowrap">--web.read-timeout</code> | Maximum duration before timing out read of the request, and closing idle connections. | `5m` |
-| <code class="text-nowrap">--web.max-connections</code> | Maximum number of simultaneous connections. | `512` |
+| <code class="text-nowrap">--web.max-connections</code> | Maximum number of simultaneous connections across all listeners. | `512` |
 | <code class="text-nowrap">--web.external-url</code> | The URL under which Prometheus is externally reachable (for example, if Prometheus is served via a reverse proxy). Used for generating relative and absolute links back to Prometheus itself. If the URL has a path portion, it will be used to prefix all HTTP endpoints served by Prometheus. If omitted, relevant URL components will be derived automatically. |  |
 | <code class="text-nowrap">--web.route-prefix</code> | Prefix for the internal routes of web endpoints. Defaults to path of --web.external-url. |  |
 | <code class="text-nowrap">--web.user-assets</code> | Path to static asset directory, available at /user. |  |
@@ -56,7 +56,8 @@ The Prometheus monitoring server
 | <code class="text-nowrap">--query.timeout</code> | Maximum time a query may take before being aborted. Use with server mode only. | `2m` |
 | <code class="text-nowrap">--query.max-concurrency</code> | Maximum number of queries executed concurrently. Use with server mode only. | `20` |
 | <code class="text-nowrap">--query.max-samples</code> | Maximum number of samples a single query can load into memory. Note that queries will fail if they try to load more samples than this into memory, so this also limits the number of samples a query can return. Use with server mode only. | `50000000` |
-| <code class="text-nowrap">--enable-feature</code> | Comma separated feature names to enable. Valid options: agent, auto-gomemlimit, exemplar-storage, expand-external-labels, memory-snapshot-on-shutdown, promql-per-step-stats, promql-experimental-functions, remote-write-receiver (DEPRECATED), extra-scrape-metrics, new-service-discovery-manager, auto-gomaxprocs, no-default-scrape-port, native-histograms, otlp-write-receiver, created-timestamp-zero-ingestion, concurrent-rule-eval, new-ui. See https://prometheus.io/docs/prometheus/latest/feature_flags/ for more details. |  |
+| <code class="text-nowrap">--scrape.name-escaping-scheme</code> | Method for escaping legacy invalid names when sending to Prometheus that does not support UTF-8. Can be one of "values", "underscores", or "dots". | `values` |
+| <code class="text-nowrap">--enable-feature</code> <code class="text-nowrap">...<code class="text-nowrap"> | Comma separated feature names to enable. Valid options: agent, auto-gomaxprocs, auto-gomemlimit, concurrent-rule-eval, created-timestamp-zero-ingestion, delayed-compaction, exemplar-storage, expand-external-labels, extra-scrape-metrics, memory-snapshot-on-shutdown, native-histograms, new-service-discovery-manager, new-ui, no-default-scrape-port, otlp-write-receiver, promql-experimental-functions, promql-delayed-name-removal, promql-per-step-stats, remote-write-receiver (DEPRECATED), utf8-names. See https://prometheus.io/docs/prometheus/latest/feature_flags/ for more details. |  |
 | <code class="text-nowrap">--log.level</code> | Only log messages with the given severity or above. One of: [debug, info, warn, error] | `info` |
 | <code class="text-nowrap">--log.format</code> | Output format of log messages. One of: [logfmt, json] | `logfmt` |
 

docs/command-line/promtool.md

@@ -15,7 +15,7 @@ Tooling for the Prometheus monitoring system.
 | <code class="text-nowrap">-h</code>, <code class="text-nowrap">--help</code> | Show context-sensitive help (also try --help-long and --help-man). |
 | <code class="text-nowrap">--version</code> | Show application version. |
 | <code class="text-nowrap">--experimental</code> | Enable experimental commands. |
-| <code class="text-nowrap">--enable-feature</code> | Comma separated feature names to enable (only PromQL related and no-default-scrape-port). See https://prometheus.io/docs/prometheus/latest/feature_flags/ for the options and more details. |
+| <code class="text-nowrap">--enable-feature</code> <code class="text-nowrap">...<code class="text-nowrap"> | Comma separated feature names to enable (only PromQL related and no-default-scrape-port). See https://prometheus.io/docs/prometheus/latest/feature_flags/ for the options and more details. |
 
 
 
@@ -281,7 +281,7 @@ Run series query.
 
 | Flag | Description |
 | --- | --- |
-| <code class="text-nowrap">--match</code> | Series selector. Can be specified multiple times. |
+| <code class="text-nowrap">--match</code> <code class="text-nowrap">...<code class="text-nowrap"> | Series selector. Can be specified multiple times. |
 | <code class="text-nowrap">--start</code> | Start time (RFC3339 or Unix timestamp). |
 | <code class="text-nowrap">--end</code> | End time (RFC3339 or Unix timestamp). |
 
@@ -309,7 +309,7 @@ Run labels query.
 | --- | --- |
 | <code class="text-nowrap">--start</code> | Start time (RFC3339 or Unix timestamp). |
 | <code class="text-nowrap">--end</code> | End time (RFC3339 or Unix timestamp). |
-| <code class="text-nowrap">--match</code> | Series selector. Can be specified multiple times. |
+| <code class="text-nowrap">--match</code> <code class="text-nowrap">...<code class="text-nowrap"> | Series selector. Can be specified multiple times. |
 
 
 
@@ -338,7 +338,7 @@ Run queries against your Prometheus to analyze the usage pattern of certain metr
 | <code class="text-nowrap">--type</code> | Type of metric: histogram. |  |
 | <code class="text-nowrap">--duration</code> | Time frame to analyze. | `1h` |
 | <code class="text-nowrap">--time</code> | Query time (RFC3339 or Unix timestamp), defaults to now. |  |
-| <code class="text-nowrap">--match</code> | Series selector. Can be specified multiple times. |  |
+| <code class="text-nowrap">--match</code> <code class="text-nowrap">...<code class="text-nowrap"> | Series selector. Can be specified multiple times. |  |
 
 
 
@@ -461,7 +461,7 @@ Unit tests for rules.
 
 | Flag | Description | Default |
 | --- | --- | --- |
-| <code class="text-nowrap">--run</code> | If set, will only run test groups whose names match the regular expression. Can be specified multiple times. |  |
+| <code class="text-nowrap">--run</code> <code class="text-nowrap">...<code class="text-nowrap"> | If set, will only run test groups whose names match the regular expression. Can be specified multiple times. |  |
 | <code class="text-nowrap">--diff</code> | [Experimental] Print colored differential output between expected & received output. | `false` |
 
 
@@ -578,7 +578,7 @@ Dump samples from a TSDB.
 | <code class="text-nowrap">--sandbox-dir-root</code> | Root directory where a sandbox directory would be created in case WAL replay generates chunks. The sandbox directory is cleaned up at the end. | `data/` |
 | <code class="text-nowrap">--min-time</code> | Minimum timestamp to dump. | `-9223372036854775808` |
 | <code class="text-nowrap">--max-time</code> | Maximum timestamp to dump. | `9223372036854775807` |
-| <code class="text-nowrap">--match</code> | Series selector. Can be specified multiple times. | `{__name__=~'(?s:.*)'}` |
+| <code class="text-nowrap">--match</code> <code class="text-nowrap">...<code class="text-nowrap"> | Series selector. Can be specified multiple times. | `{__name__=~'(?s:.*)'}` |
 
 
 
@@ -605,7 +605,7 @@ Dump samples from a TSDB.
 | <code class="text-nowrap">--sandbox-dir-root</code> | Root directory where a sandbox directory would be created in case WAL replay generates chunks. The sandbox directory is cleaned up at the end. | `data/` |
 | <code class="text-nowrap">--min-time</code> | Minimum timestamp to dump. | `-9223372036854775808` |
 | <code class="text-nowrap">--max-time</code> | Maximum timestamp to dump. | `9223372036854775807` |
-| <code class="text-nowrap">--match</code> | Series selector. Can be specified multiple times. | `{__name__=~'(?s:.*)'}` |
+| <code class="text-nowrap">--match</code> <code class="text-nowrap">...<code class="text-nowrap"> | Series selector. Can be specified multiple times. | `{__name__=~'(?s:.*)'}` |
 
 
 
@@ -641,6 +641,15 @@ Import samples from OpenMetrics input and produce TSDB blocks. Please refer to t
 
 
 
+###### Flags
+
+| Flag | Description |
+| --- | --- |
+| <code class="text-nowrap">--label</code> | Label to attach to metrics. Can be specified multiple times. Example --label=label_name=label_value |
+
+
+
+
 ###### Arguments
 
 | Argument | Description | Default | Required |

docs/configuration/configuration.md

@@ -121,6 +121,11 @@ global:
   # that will be kept in memory. 0 means no limit.
   [ keep_dropped_targets: <int> | default = 0 ]
 
+  # Specifies the validation scheme for metric and label names. Either blank or
+  # "legacy" for letters, numbers, colons, and underscores; or "utf8" for full
+  # UTF-8 support.
+  [ metric_name_validation_scheme <string> | default "legacy" ]
+
 runtime:
   # Configure the Go garbage collector GOGC parameter
   # See: https://tip.golang.org/doc/gc-guide#GOGC
@@ -302,6 +307,17 @@ tls_config:
 [ proxy_connect_header:
   [ <string>: [<secret>, ...] ] ]
 
+# Custom HTTP headers to be sent along with each request.
+# Headers that are set by Prometheus itself can't be overwritten.
+http_headers:
+  # Header name.
+  [ <string>:
+    # Header values.
+    [ values: [<string>, ...] ]
+    # Headers values. Hidden in configuration page.
+    [ secrets: [<secret>, ...] ]
+    # Files to read header values from.
+    [ files: [<string>, ...] ] ]
 
 # List of Azure service discovery configurations.
 azure_sd_configs:
@@ -461,6 +477,11 @@ metric_relabel_configs:
 # that will be kept in memory. 0 means no limit.
 [ keep_dropped_targets: <int> | default = 0 ]
 
+# Specifies the validation scheme for metric and label names. Either blank or
+# "legacy" for letters, numbers, colons, and underscores; or "utf8" for full
+# UTF-8 support.
+[ metric_name_validation_scheme <string> | default "legacy" ]
+
 # Limit on total number of positive and negative buckets allowed in a single
 # native histogram. The resolution of a histogram with more buckets will be
 # reduced until the number of buckets is within the limit. If the limit cannot
@@ -947,7 +968,9 @@ tls_config:
 # The host to use if the container is in host networking mode.
 [ host_networking_host: <string> | default = "localhost" ]
 
-# Match the first network if the container has multiple networks defined, thus avoiding collecting duplicate targets.
+# Sort all non-nil networks in ascending order based on network name and
+# get the first network if the container has multiple networks defined, 
+# thus avoiding collecting duplicate targets.
 [ match_first_network: <boolean> | default = true ]
 
 # Optional filters to limit the discovery process to a subset of available
@@ -3265,12 +3288,16 @@ Initially, aside from the configured per-target labels, a target's `job`
 label is set to the `job_name` value of the respective scrape configuration.
 The `__address__` label is set to the `<host>:<port>` address of the target.
 After relabeling, the `instance` label is set to the value of `__address__` by default if
-it was not set during relabeling. The `__scheme__` and `__metrics_path__` labels
+it was not set during relabeling.
-are set to the scheme and metrics path of the target respectively. The `__param_<name>`
+
-label is set to the value of the first passed URL parameter called `<name>`.
+The `__scheme__` and `__metrics_path__` labels
+are set to the scheme and metrics path of the target respectively, as specified in `scrape_config`.
+
+The `__param_<name>`
+label is set to the value of the first passed URL parameter called `<name>`, as defined in `scrape_config`.
 
 The `__scrape_interval__` and `__scrape_timeout__` labels are set to the target's
-interval and timeout.
+interval and timeout, as specified in `scrape_config`.
 
 Additional labels prefixed with `__meta_` may be available during the
 relabeling phase. They are set by the service discovery mechanism that provided

docs/feature_flags.md

@@ -200,8 +200,9 @@ won't work when you push OTLP metrics.
 
 `--enable-feature=promql-experimental-functions`
 
-Enables PromQL functions that are considered experimental and whose name or
+Enables PromQL functions that are considered experimental. These functions
-semantics could change.
+might change their name, syntax, or semantics. They might also get removed
+entirely.
 
 ## Created Timestamps Zero Injection
 
@@ -240,3 +241,33 @@ metadata changes as WAL records on a per-series basis.
 
 This must be used if
 you are also using remote write 2.0 as it will only gather metadata from the WAL.
+
+## Delay compaction start time
+
+`--enable-feature=delayed-compaction`
+
+A random offset, up to `10%` of the chunk range, is added to the Head compaction start time. This assists Prometheus instances in avoiding simultaneous compactions and reduces the load on shared resources.
+
+Only auto Head compactions and the operations directly resulting from them are subject to this delay.
+
+In the event of multiple consecutive Head compactions being possible, only the first compaction experiences this delay.
+
+Note that during this delay, the Head continues its usual operations, which include serving and appending series.
+
+Despite the delay in compaction, the blocks produced are time-aligned in the same manner as they would be if the delay was not in place.
+
+## Delay __name__ label removal for PromQL engine
+
+`--enable-feature=promql-delayed-name-removal`
+
+When enabled, Prometheus will change the way in which the `__name__` label is removed from PromQL query results (for functions and expressions for which this is necessary). Specifically, it will delay the removal to the last step of the query evaluation, instead of every time an expression or function creating derived metrics is evaluated.
+
+This allows optionally preserving the `__name__` label via the `label_replace` and `label_join` functions, and helps prevent the "vector cannot contain metrics with the same labelset" error, which can happen when applying a regex-matcher to the `__name__` label.
+
+## UTF-8 Name Support
+
+`--enable-feature=utf8-names`
+
+When enabled, changes the metric and label name validation scheme inside Prometheus to allow the full UTF-8 character set.
+By itself, this flag does not enable the request of UTF-8 names via content negotiation.
+Users will also have to set `metric_name_validation_scheme` in scrape configs to enable the feature either on the global config or on a per-scrape config basis.

docs/querying/basics.md

@@ -41,7 +41,7 @@ vector is the only type which can be graphed.
 _Notes about the experimental native histograms:_
 
 * Ingesting native histograms has to be enabled via a [feature
-  flag](../../feature_flags.md#native-histograms).
+  flag](../feature_flags.md#native-histograms).
 * Once native histograms have been ingested into the TSDB (and even after
   disabling the feature flag again), both instant vectors and range vectors may
   now contain samples that aren't simple floating point numbers (float samples)

docs/querying/functions.md

@@ -617,9 +617,9 @@ Like `sort`, `sort_desc` only affects the results of instant queries, as range q
 
 ## `sort_by_label()`
 
-**This function has to be enabled via the [feature flag](../feature_flags/) `--enable-feature=promql-experimental-functions`.**
+**This function has to be enabled via the [feature flag](../feature_flags.md#experimental-promql-functions) `--enable-feature=promql-experimental-functions`.**
 
-`sort_by_label(v instant-vector, label string, ...)` returns vector elements sorted by their label values and sample value in case of label values being equal, in ascending order.
+`sort_by_label(v instant-vector, label string, ...)` returns vector elements sorted by the values of the given labels in ascending order. In case these label values are equal, elements are sorted by their full label sets.
 
 Please note that the sort by label functions only affect the results of instant queries, as range query results always have a fixed output ordering.
 
@@ -627,7 +627,7 @@ This function uses [natural sort order](https://en.wikipedia.org/wiki/Natural_so
 
 ## `sort_by_label_desc()`
 
-**This function has to be enabled via the [feature flag](../feature_flags/) `--enable-feature=promql-experimental-functions`.**
+**This function has to be enabled via the [feature flag](../feature_flags.md#experimental-promql-functions) `--enable-feature=promql-experimental-functions`.**
 
 Same as `sort_by_label`, but sorts in descending order.
 
@@ -676,7 +676,7 @@ over time and return an instant vector with per-series aggregation results:
 * `last_over_time(range-vector)`: the most recent point value in the specified interval.
 * `present_over_time(range-vector)`: the value 1 for any series in the specified interval.
 
-If the [feature flag](../feature_flags/)
+If the [feature flag](../feature_flags.md#experimental-promql-functions)
 `--enable-feature=promql-experimental-functions` is set, the following
 additional functions are available:
 

documentation/examples/remote_storage/example_write_adapter/README.md

@@ -19,7 +19,7 @@ remote_write:
     protobuf_message: "io.prometheus.write.v2.Request"
 ```
 
-or for deprecated Remote Write 1.0 message:
+or for the eventually deprecated Remote Write 1.0 message:
 
 ```yaml
 remote_write:

documentation/examples/remote_storage/go.mod

@@ -8,19 +8,19 @@ require (
 	github.com/gogo/protobuf v1.3.2
 	github.com/golang/snappy v0.0.4
 	github.com/influxdata/influxdb v1.11.5
-	github.com/prometheus/client_golang v1.19.1
+	github.com/prometheus/client_golang v1.20.0
-	github.com/prometheus/common v0.55.0
+	github.com/prometheus/common v0.57.0
 	github.com/prometheus/prometheus v0.53.1
 	github.com/stretchr/testify v1.9.0
 )
 
 require (
 	github.com/Azure/azure-sdk-for-go/sdk/azcore v1.11.1 // indirect
-	github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.5.2 // indirect
+	github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.6.0 // indirect
-	github.com/Azure/azure-sdk-for-go/sdk/internal v1.6.0 // indirect
+	github.com/Azure/azure-sdk-for-go/sdk/internal v1.8.0 // indirect
 	github.com/AzureAD/microsoft-authentication-library-for-go v1.2.2 // indirect
 	github.com/alecthomas/units v0.0.0-20231202071711-9a357b53e9c9 // indirect
-	github.com/aws/aws-sdk-go v1.53.16 // indirect
+	github.com/aws/aws-sdk-go v1.55.5 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/cespare/xxhash/v2 v2.3.0 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
@@ -35,8 +35,7 @@ require (
 	github.com/jmespath/go-jmespath v0.4.0 // indirect
 	github.com/jpillora/backoff v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
-	github.com/klauspost/compress v1.17.8 // indirect
+	github.com/klauspost/compress v1.17.9 // indirect
-	github.com/kr/text v0.2.0 // indirect
 	github.com/kylelemons/godebug v1.1.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
@@ -56,14 +55,14 @@ require (
 	go.opentelemetry.io/otel/trace v1.27.0 // indirect
 	go.uber.org/atomic v1.11.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
-	golang.org/x/crypto v0.24.0 // indirect
+	golang.org/x/crypto v0.25.0 // indirect
-	golang.org/x/net v0.26.0 // indirect
+	golang.org/x/net v0.27.0 // indirect
 	golang.org/x/oauth2 v0.21.0 // indirect
-	golang.org/x/sys v0.21.0 // indirect
+	golang.org/x/sys v0.22.0 // indirect
 	golang.org/x/text v0.16.0 // indirect
 	golang.org/x/time v0.5.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20240528184218-531527333157 // indirect
-	google.golang.org/grpc v1.64.0 // indirect
+	google.golang.org/grpc v1.65.0 // indirect
 	google.golang.org/protobuf v1.34.2 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect

documentation/examples/remote_storage/go.sum

@@ -1,9 +1,9 @@
 github.com/Azure/azure-sdk-for-go/sdk/azcore v1.11.1 h1:E+OJmp2tPvt1W+amx48v1eqbjDYsgN+RzP4q16yV5eM=
 github.com/Azure/azure-sdk-for-go/sdk/azcore v1.11.1/go.mod h1:a6xsAQUZg+VsS3TJ05SRp524Hs4pZ/AeFSr5ENf0Yjo=
-github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.5.2 h1:FDif4R1+UUR+00q6wquyX90K7A8dN+R5E8GEadoP7sU=
+github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.6.0 h1:U2rTu3Ef+7w9FHKIAXM6ZyqF3UOWJZ12zIm8zECAFfg=
-github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.5.2/go.mod h1:aiYBYui4BJ/BJCAIKs92XiPyQfTaBWqvHujDwKb6CBU=
+github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.6.0/go.mod h1:9kIvujWAA58nmPmWB1m23fyWic1kYZMxD9CxaWn4Qpg=
-github.com/Azure/azure-sdk-for-go/sdk/internal v1.6.0 h1:sUFnFjzDUie80h24I7mrKtwCKgLY9L8h5Tp2x9+TWqk=
+github.com/Azure/azure-sdk-for-go/sdk/internal v1.8.0 h1:jBQA3cKT4L2rWMpgE7Yt3Hwh2aUj8KXjIGLxjHeYNNo=
-github.com/Azure/azure-sdk-for-go/sdk/internal v1.6.0/go.mod h1:52JbnQTp15qg5mRkMBHwp0j0ZFwHJ42Sx3zVV5RE9p0=
+github.com/Azure/azure-sdk-for-go/sdk/internal v1.8.0/go.mod h1:4OG6tQ9EOP/MT0NMjDlRzWoVFxfu9rN9B2X+tlSVktg=
 github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/compute/armcompute/v5 v5.7.0 h1:LkHbJbgF3YyvC53aqYGR+wWQDn2Rdp9AQdGndf9QvY4=
 github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/compute/armcompute/v5 v5.7.0/go.mod h1:QyiQdW4f4/BIfB8ZutZ2s+28RAgfa/pT+zS++ZHyM1I=
 github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/network/armnetwork/v4 v4.3.0 h1:bXwSugBiSbgtz7rOtbfGf+woewp4f06orW9OP5BjHLA=
@@ -26,8 +26,8 @@ github.com/alecthomas/units v0.0.0-20231202071711-9a357b53e9c9/go.mod h1:OMCwj8V
 github.com/armon/go-metrics v0.4.1 h1:hR91U9KYmb6bLBYLQjyM+3j+rcd/UhE+G78SFnF8gJA=
 github.com/armon/go-metrics v0.4.1/go.mod h1:E6amYzXo6aW1tqzoZGT755KkbgrJsSdpwZ+3JqfkOG4=
 github.com/aws/aws-sdk-go v1.38.35/go.mod h1:hcU610XS61/+aQV88ixoOzUoG7v3b31pl2zKMmprdro=
-github.com/aws/aws-sdk-go v1.53.16 h1:8oZjKQO/ml1WLUZw5hvF7pvYjPf8o9f57Wldoy/q9Qc=
+github.com/aws/aws-sdk-go v1.55.5 h1:KKUZBfBoyqy5d3swXyiC7Q76ic40rYcbqH7qjh59kzU=
-github.com/aws/aws-sdk-go v1.53.16/go.mod h1:LF8svs817+Nz+DmiMQKTO3ubZ/6IaTpq3TjupRn3Eqk=
+github.com/aws/aws-sdk-go v1.55.5/go.mod h1:eRwEWoyTWFMVYVQzKMNHWP5/RV4xIUGMQfXQHfHkpNU=
 github.com/bboreham/go-loser v0.0.0-20230920113527-fcc2c21820a3 h1:6df1vn4bBlDDo4tARvBm7l6KA9iVMnE3NWizDeWSrps=
 github.com/bboreham/go-loser v0.0.0-20230920113527-fcc2c21820a3/go.mod h1:CIWtjkly68+yqLPbvwwR/fjNJA/idrtULjZWh2v1ys0=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
@@ -37,9 +37,8 @@ github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6r
 github.com/cespare/xxhash/v2 v2.1.1/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
-github.com/cncf/xds/go v0.0.0-20240318125728-8a4994d93e50 h1:DBmgJDC9dTfkVyGgipamEh2BpGYxScCH1TOF1LL1cXc=
+github.com/cncf/xds/go v0.0.0-20240423153145-555b57ec207b h1:ga8SEFjZ60pxLcmhnThWgvH2wg8376yUJmPhEH4H3kw=
-github.com/cncf/xds/go v0.0.0-20240318125728-8a4994d93e50/go.mod h1:5e1+Vvlzido69INQaVO6d87Qn543Xr6nooe9Kz7oBFM=
+github.com/cncf/xds/go v0.0.0-20240423153145-555b57ec207b/go.mod h1:W+zGtBO5Y1IgJhy4+A9GOqVhqLpfZi+vwmdNXUehLA8=
-github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
@@ -50,8 +49,6 @@ github.com/digitalocean/godo v1.117.0 h1:WVlTe09melDYTd7VCVyvHcNWbgB+uI1O115+5LO
 github.com/digitalocean/godo v1.117.0/go.mod h1:Vk0vpCot2HOAJwc5WE8wljZGtJ3ZtWIc8MQ8rF38sdo=
 github.com/distribution/reference v0.5.0 h1:/FUIFXtfc/x2gpa5/VGfiGLuOIdYa1t65IKK2OFGvA0=
 github.com/distribution/reference v0.5.0/go.mod h1:BbU0aIcezP1/5jX/8MP0YiH4SdvB5Y4f/wlDRiLyi3E=
-github.com/dnaeon/go-vcr v1.2.0 h1:zHCHvJYTMh1N7xnV7zf1m1GPBF9Ad0Jk/whtQ1663qI=
-github.com/dnaeon/go-vcr v1.2.0/go.mod h1:R4UdLID7HZT3taECzJs4YgbbH6PIGXB6W/sc5OLb6RQ=
 github.com/docker/docker v26.1.3+incompatible h1:lLCzRbrVZrljpVNobJu1J2FHk8V0s4BawoZippkc+xo=
 github.com/docker/docker v26.1.3+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/go-connections v0.4.0 h1:El9xVISelRB7BuFusrZozjnkIM5YnzCViNKohAFqRJQ=
@@ -190,8 +187,8 @@ github.com/julienschmidt/httprouter v1.2.0/go.mod h1:SYymIcj16QtmaHHD7aYtjjsJG7V
 github.com/julienschmidt/httprouter v1.3.0/go.mod h1:JR6WtHb+2LUe8TCKY3cZOxFyyO8IZAc4RVcycCCAKdM=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
-github.com/klauspost/compress v1.17.8 h1:YcnTYrq7MikUT7k0Yb5eceMmALQPYBW/Xltxn0NAMnU=
+github.com/klauspost/compress v1.17.9 h1:6KIumPrER1LHsvBVuDa0r5xaG0Es51mhhB9BQB2qeMA=
-github.com/klauspost/compress v1.17.8/go.mod h1:Di0epgTjJY877eYKx5yC51cX2A2Vl2ibi7bDH9ttBbw=
+github.com/klauspost/compress v1.17.9/go.mod h1:Di0epgTjJY877eYKx5yC51cX2A2Vl2ibi7bDH9ttBbw=
 github.com/kolo/xmlrpc v0.0.0-20220921171641-a4b6fa1dd06b h1:udzkj9S/zlT5X367kqJis0QP7YMxobob6zhzq6Yre00=
 github.com/kolo/xmlrpc v0.0.0-20220921171641-a4b6fa1dd06b/go.mod h1:pcaDhQK0/NJZEvtCO0qQPPropqV0sJOJ6YW7X+9kRwM=
 github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
@@ -256,8 +253,8 @@ github.com/prometheus/client_golang v0.9.1/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXP
 github.com/prometheus/client_golang v1.0.0/go.mod h1:db9x61etRT2tGnBNRi70OPL5FsnadC4Ky3P0J6CfImo=
 github.com/prometheus/client_golang v1.7.1/go.mod h1:PY5Wy2awLA44sXw4AOSfFBetzPP4j5+D6mVACh+pe2M=
 github.com/prometheus/client_golang v1.11.0/go.mod h1:Z6t4BnS23TR94PD6BsDNk8yVqroYurpAkEiz0P2BEV0=
-github.com/prometheus/client_golang v1.19.1 h1:wZWJDwK+NameRJuPGDhlnFgx8e8HN3XHQeLaYJFJBOE=
+github.com/prometheus/client_golang v1.20.0 h1:jBzTZ7B099Rg24tny+qngoynol8LtVYlA2bqx3vEloI=
-github.com/prometheus/client_golang v1.19.1/go.mod h1:mP78NwGzrVks5S2H6ab8+ZZGJLZUq1hoULYBAYBw1Ho=
+github.com/prometheus/client_golang v1.20.0/go.mod h1:PIEt8X02hGcP8JWbeHyeZ53Y/jReSnHgO035n//V5WE=
 github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910/go.mod h1:MbSGuTsp3dbXC40dX6PRTWyKYBIrTGTE9sqQNg2J8bo=
 github.com/prometheus/client_model v0.0.0-20190129233127-fd36f4220a90/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/prometheus/client_model v0.2.0/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
@@ -267,8 +264,8 @@ github.com/prometheus/common v0.4.1/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y8
 github.com/prometheus/common v0.10.0/go.mod h1:Tlit/dnDKsSWFlCLTWaA1cyBgKHSMdTB80sz/V91rCo=
 github.com/prometheus/common v0.26.0/go.mod h1:M7rCNAaPfAosfx8veZJCuw84e35h3Cfd9VFqTh1DIvc=
 github.com/prometheus/common v0.29.0/go.mod h1:vu+V0TpY+O6vW9J44gczi3Ap/oXXR10b+M/gUGO4Hls=
-github.com/prometheus/common v0.55.0 h1:KEi6DK7lXW/m7Ig5i47x0vRzuBsHuvJdi5ee6Y3G1dc=
+github.com/prometheus/common v0.57.0 h1:Ro/rKjwdq9mZn1K5QPctzh+MA4Lp0BuYk5ZZEVhoNcY=
-github.com/prometheus/common v0.55.0/go.mod h1:2SECS4xJG1kd8XF9IcM1gMX6510RAEL65zxzNImwdc8=
+github.com/prometheus/common v0.57.0/go.mod h1:7uRPFSUTbfZWsJ7MHY56sqt7hLQu3bxXHDnNhl8E9qI=
 github.com/prometheus/common/sigv4 v0.1.0 h1:qoVebwtwwEhS85Czm2dSROY5fTo2PAPEVdDeppTwGX4=
 github.com/prometheus/common/sigv4 v0.1.0/go.mod h1:2Jkxxk9yYvCkE5G1sQT7GuEXm57JrvHu9k5YwTjsNtI=
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
@@ -279,8 +276,8 @@ github.com/prometheus/procfs v0.15.1 h1:YagwOFzUgYfKKHX6Dr+sHT7km/hxC76UB0leargg
 github.com/prometheus/procfs v0.15.1/go.mod h1:fB45yRUv8NstnjriLhBQLuOUt+WW4BsoGhij/e3PBqk=
 github.com/prometheus/prometheus v0.53.1-0.20240704074759-c137febfcf8c h1:6GEA48LnonkYZhQ654v7QTIP5uBTbCEVm49oIhif5lc=
 github.com/prometheus/prometheus v0.53.1-0.20240704074759-c137febfcf8c/go.mod h1:FcNs5wa7M9yV8IlxlB/05s5oy9vULUIlu/tZsviRIT8=
-github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
+github.com/rogpeppe/go-internal v1.12.0 h1:exVL4IDcn6na9z1rAb56Vxr+CgyK3nn3O+epU5NdKM8=
-github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
+github.com/rogpeppe/go-internal v1.12.0/go.mod h1:E+RYuTGaKKdloAfM02xzb0FW3Paa99yedzYV+kq4uf4=
 github.com/scaleway/scaleway-sdk-go v1.0.0-beta.27 h1:yGAraK1uUjlhSXgNMIy8o/J4LFNcy7yeipBqt9N9mVg=
 github.com/scaleway/scaleway-sdk-go v1.0.0-beta.27/go.mod h1:fCa7OJZ/9DRTnOKmxvT6pn+LPWUptQAmHF/SBJUGEcg=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
@@ -326,8 +323,8 @@ golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnf
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.24.0 h1:mnl8DM0o513X8fdIkmyFE/5hTYxbwYOjDS/+rK6qpRI=
+golang.org/x/crypto v0.25.0 h1:ypSNr+bnYL2YhwoMt2zPxHFmbAN1KZs/njMG3hxUp30=
-golang.org/x/crypto v0.24.0/go.mod h1:Z1PMYSOR5nyMcyAVAIQSKCDwalqy85Aqn1x3Ws4L5DM=
+golang.org/x/crypto v0.25.0/go.mod h1:T+wALwcMOSE0kXgUAnPAHqTLW+XHgcELELW8VaDgm/M=
 golang.org/x/exp v0.0.0-20240119083558-1b970713d09a h1:Q8/wZp0KX97QFTc2ywcOE0YRjZPVIx+MXInMzdvQqcA=
 golang.org/x/exp v0.0.0-20240119083558-1b970713d09a/go.mod h1:idGWGoKP1toJGkd5/ig9ZLuPcZBC3ewk7SzmH0uou08=
 golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
@@ -347,8 +344,8 @@ golang.org/x/net v0.0.0-20200822124328-c89045814202/go.mod h1:/O7V0waA8r7cgGh81R
 golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20201110031124-69a78807bb2b/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/net v0.0.0-20210525063256-abc453219eb5/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/net v0.26.0 h1:soB7SVo0PWrY4vPW/+ay0jKDNScG2X9wFeYlXIvJsOQ=
+golang.org/x/net v0.27.0 h1:5K3Njcw06/l2y9vpGCSdcxWOYHOUk3dVNGDXN+FvAys=
-golang.org/x/net v0.26.0/go.mod h1:5YKkiSynbBIh3p6iOc/vibscux0x38BZDkn8sCUPxHE=
+golang.org/x/net v0.27.0/go.mod h1:dDi0PyhWNoiUOrAS8uXv/vnScO4wnHQO4mj9fn/RytE=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
 golang.org/x/oauth2 v0.21.0 h1:tsimM75w1tF/uws5rbeHzIWxEqElMehnc+iW793zsZs=
@@ -376,11 +373,11 @@ golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210603081109-ebe580a85c40/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.1.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.21.0 h1:rF+pYz3DAGSQAxAu1CbC7catZg4ebC4UIeIhKxBZvws=
+golang.org/x/sys v0.22.0 h1:RI27ohtqKCnwULzJLqkv897zojh5/DwS/ENaMzUOaWI=
-golang.org/x/sys v0.21.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.22.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/term v0.21.0 h1:WVXCp+/EBEHOj53Rvu+7KiT/iElMrO8ACK16SMZ3jaA=
+golang.org/x/term v0.22.0 h1:BbsgPEJULsl2fV/AT3v15Mjva5yXKQDyKf+TbDz7QJk=
-golang.org/x/term v0.21.0/go.mod h1:ooXLefLobQVslOqselCNF4SxFAaoS6KujMbsGzSDmX0=
+golang.org/x/term v0.22.0/go.mod h1:F3qCibpT5AMpCRfhfT53vVJwhLtIVHhB9XDjfFvnMI4=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
 golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
@@ -405,8 +402,8 @@ google.golang.org/genproto/googleapis/api v0.0.0-20240528184218-531527333157 h1:
 google.golang.org/genproto/googleapis/api v0.0.0-20240528184218-531527333157/go.mod h1:99sLkeliLXfdj2J75X3Ho+rrVCaJze0uwN7zDDkjPVU=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240528184218-531527333157 h1:Zy9XzmMEflZ/MAaA7vNcoebnRAld7FsPW1EeBB7V0m8=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240528184218-531527333157/go.mod h1:EfXuqaE1J41VCDicxHzUDm+8rk+7ZdXzHV0IhO/I6s0=
-google.golang.org/grpc v1.64.0 h1:KH3VH9y/MgNQg1dE7b3XfVK0GsPSIzJwdF617gUSbvY=
+google.golang.org/grpc v1.65.0 h1:bs/cUb4lp1G5iImFFd3u5ixQzweKizoZJAwBNLR42lc=
-google.golang.org/grpc v1.64.0/go.mod h1:oxjF8E3FBnjp+/gVFYdWacaLDx9na1aqy9oovLpxQYg=
+google.golang.org/grpc v1.65.0/go.mod h1:WgYC2ypjlB0EiQi6wdKixMqukr6lBc0Vo+oOgjrM5ZQ=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
 google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=

go.mod

@@ -13,15 +13,15 @@ require (
 	github.com/KimMachineGun/automemlimit v0.6.1
 	github.com/alecthomas/kingpin/v2 v2.4.0
 	github.com/alecthomas/units v0.0.0-20240626203959-61d1e3462e30
-	github.com/aws/aws-sdk-go v1.54.19
+	github.com/aws/aws-sdk-go v1.55.5
 	github.com/bboreham/go-loser v0.0.0-20230920113527-fcc2c21820a3
 	github.com/cespare/xxhash/v2 v2.3.0
 	github.com/dennwc/varint v1.0.0
 	github.com/digitalocean/godo v1.119.0
-	github.com/docker/docker v27.0.3+incompatible
+	github.com/docker/docker v27.1.1+incompatible
 	github.com/edsrzf/mmap-go v1.1.0
 	github.com/envoyproxy/go-control-plane v0.12.0
-	github.com/envoyproxy/protoc-gen-validate v1.0.4
+	github.com/envoyproxy/protoc-gen-validate v1.1.0
 	github.com/facette/natsort v0.0.0-20181210072756-2cd4dd1e2dcb
 	github.com/fsnotify/fsnotify v1.7.0
 	github.com/go-kit/log v0.2.1
@@ -36,10 +36,10 @@ require (
 	github.com/gophercloud/gophercloud v1.14.0
 	github.com/grafana/regexp v0.0.0-20240518133315-a468a5bfb3bc
 	github.com/grpc-ecosystem/grpc-gateway v1.16.0
-	github.com/hashicorp/consul/api v1.29.2
+	github.com/hashicorp/consul/api v1.29.4
 	github.com/hashicorp/nomad/api v0.0.0-20240717122358-3d93bd3778f3
-	github.com/hetznercloud/hcloud-go/v2 v2.12.0
+	github.com/hetznercloud/hcloud-go/v2 v2.13.1
-	github.com/ionos-cloud/sdk-go/v6 v6.1.11
+	github.com/ionos-cloud/sdk-go/v6 v6.2.1
 	github.com/json-iterator/go v1.1.12
 	github.com/klauspost/compress v1.17.9
 	github.com/kolo/xmlrpc v0.0.0-20220921171641-a4b6fa1dd06b
@@ -52,9 +52,9 @@ require (
 	github.com/oklog/ulid v1.3.1
 	github.com/ovh/go-ovh v1.6.0
 	github.com/prometheus/alertmanager v0.27.0
-	github.com/prometheus/client_golang v1.19.1
+	github.com/prometheus/client_golang v1.20.2
 	github.com/prometheus/client_model v0.6.1
-	github.com/prometheus/common v0.55.0
+	github.com/prometheus/common v0.56.0
 	github.com/prometheus/common/assets v0.2.0
 	github.com/prometheus/common/sigv4 v0.1.0
 	github.com/prometheus/exporter-toolkit v0.11.0
@@ -75,15 +75,14 @@ require (
 	go.uber.org/automaxprocs v1.5.3
 	go.uber.org/goleak v1.3.0
 	go.uber.org/multierr v1.11.0
-	golang.org/x/net v0.27.0
+	golang.org/x/oauth2 v0.22.0
-	golang.org/x/oauth2 v0.21.0
 	golang.org/x/sync v0.7.0
 	golang.org/x/sys v0.22.0
 	golang.org/x/text v0.16.0
 	golang.org/x/time v0.5.0
 	golang.org/x/tools v0.23.0
-	google.golang.org/api v0.189.0
+	google.golang.org/api v0.190.0
-	google.golang.org/genproto/googleapis/api v0.0.0-20240711142825-46eb208f015d
+	google.golang.org/genproto/googleapis/api v0.0.0-20240725223205-93522f1f2a9f
 	google.golang.org/grpc v1.65.0
 	google.golang.org/protobuf v1.34.2
 	gopkg.in/yaml.v2 v2.4.0
@@ -96,7 +95,7 @@ require (
 )
 
 require (
-	cloud.google.com/go/auth v0.7.2 // indirect
+	cloud.google.com/go/auth v0.7.3 // indirect
 	cloud.google.com/go/auth/oauth2adapt v0.2.3 // indirect
 	cloud.google.com/go/compute/metadata v0.5.0 // indirect
 	github.com/Azure/azure-sdk-for-go/sdk/internal v1.10.0 // indirect
@@ -140,9 +139,9 @@ require (
 	github.com/google/gnostic-models v0.6.8 // indirect
 	github.com/google/go-querystring v1.1.0 // indirect
 	github.com/google/gofuzz v1.2.0 // indirect
-	github.com/google/s2a-go v0.1.7 // indirect
+	github.com/google/s2a-go v0.1.8 // indirect
 	github.com/googleapis/enterprise-certificate-proxy v0.3.2 // indirect
-	github.com/googleapis/gax-go/v2 v2.12.5 // indirect
+	github.com/googleapis/gax-go/v2 v2.13.0 // indirect
 	github.com/gorilla/websocket v1.5.0 // indirect
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.20.0 // indirect
 	github.com/hashicorp/cronexpr v1.1.2 // indirect
@@ -190,8 +189,9 @@ require (
 	golang.org/x/crypto v0.25.0 // indirect
 	golang.org/x/exp v0.0.0-20240119083558-1b970713d09a // indirect
 	golang.org/x/mod v0.19.0 // indirect
+	golang.org/x/net v0.27.0 // indirect
 	golang.org/x/term v0.22.0 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20240722135656-d784300faade // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20240730163845-b1a4ccb954bf // indirect
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
 	gotest.tools/v3 v3.0.3 // indirect

go.sum

@@ -12,8 +12,8 @@ cloud.google.com/go v0.54.0/go.mod h1:1rq2OEkV3YMf6n/9ZvGWI3GWw0VoqH/1x2nd8Is/bP
 cloud.google.com/go v0.56.0/go.mod h1:jr7tqZxxKOVYizybht9+26Z/gUq7tiRzu+ACVAMbKVk=
 cloud.google.com/go v0.57.0/go.mod h1:oXiQ6Rzq3RAkkY7N6t3TcE6jE+CIBBbA36lwQ1JyzZs=
 cloud.google.com/go v0.65.0/go.mod h1:O5N8zS7uWy9vkA9vayVHs65eM1ubvY4h553ofrNHObY=
-cloud.google.com/go/auth v0.7.2 h1:uiha352VrCDMXg+yoBtaD0tUF4Kv9vrtrWPYXwutnDE=
+cloud.google.com/go/auth v0.7.3 h1:98Vr+5jMaCZ5NZk6e/uBgf60phTk/XN84r8QEWB9yjY=
-cloud.google.com/go/auth v0.7.2/go.mod h1:VEc4p5NNxycWQTMQEDQF0bd6aTMb6VgYDXEwiJJQAbs=
+cloud.google.com/go/auth v0.7.3/go.mod h1:HJtWUx1P5eqjy/f6Iq5KeytNpbAcGolPhOgyop2LlzA=
 cloud.google.com/go/auth/oauth2adapt v0.2.3 h1:MlxF+Pd3OmSudg/b1yZ5lJwoXCEaeedAguodky1PcKI=
 cloud.google.com/go/auth/oauth2adapt v0.2.3/go.mod h1:tMQXOfZzFuNuUxOypHlQEXgdfX5cuhwU+ffUuXRJE8I=
 cloud.google.com/go/bigquery v1.0.1/go.mod h1:i/xbL2UlR5RvWAURpBYZTtm/cXjCha9lbfbpx4poX+o=
@@ -92,8 +92,8 @@ github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2/go.mod h1:W
 github.com/aws/aws-lambda-go v1.13.3/go.mod h1:4UKl9IzQMoD+QF79YdCuzCwp8VbmG4VAQwij/eHl5CU=
 github.com/aws/aws-sdk-go v1.27.0/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
 github.com/aws/aws-sdk-go v1.38.35/go.mod h1:hcU610XS61/+aQV88ixoOzUoG7v3b31pl2zKMmprdro=
-github.com/aws/aws-sdk-go v1.54.19 h1:tyWV+07jagrNiCcGRzRhdtVjQs7Vy41NwsuOcl0IbVI=
+github.com/aws/aws-sdk-go v1.55.5 h1:KKUZBfBoyqy5d3swXyiC7Q76ic40rYcbqH7qjh59kzU=
-github.com/aws/aws-sdk-go v1.54.19/go.mod h1:eRwEWoyTWFMVYVQzKMNHWP5/RV4xIUGMQfXQHfHkpNU=
+github.com/aws/aws-sdk-go v1.55.5/go.mod h1:eRwEWoyTWFMVYVQzKMNHWP5/RV4xIUGMQfXQHfHkpNU=
 github.com/aws/aws-sdk-go-v2 v0.18.0/go.mod h1:JWVYvqSMppoMJC0x5wdwiImzgXTI9FuZwxzkQq9wy+g=
 github.com/bboreham/go-loser v0.0.0-20230920113527-fcc2c21820a3 h1:6df1vn4bBlDDo4tARvBm7l6KA9iVMnE3NWizDeWSrps=
 github.com/bboreham/go-loser v0.0.0-20230920113527-fcc2c21820a3/go.mod h1:CIWtjkly68+yqLPbvwwR/fjNJA/idrtULjZWh2v1ys0=
@@ -149,8 +149,8 @@ github.com/distribution/reference v0.5.0 h1:/FUIFXtfc/x2gpa5/VGfiGLuOIdYa1t65IKK
 github.com/distribution/reference v0.5.0/go.mod h1:BbU0aIcezP1/5jX/8MP0YiH4SdvB5Y4f/wlDRiLyi3E=
 github.com/dnaeon/go-vcr v1.2.0 h1:zHCHvJYTMh1N7xnV7zf1m1GPBF9Ad0Jk/whtQ1663qI=
 github.com/dnaeon/go-vcr v1.2.0/go.mod h1:R4UdLID7HZT3taECzJs4YgbbH6PIGXB6W/sc5OLb6RQ=
-github.com/docker/docker v27.0.3+incompatible h1:aBGI9TeQ4MPlhquTQKq9XbK79rKFVwXNUAYz9aXyEBE=
+github.com/docker/docker v27.1.1+incompatible h1:hO/M4MtV36kzKldqnA37IWhebRA+LnqqcqDja6kVaKY=
-github.com/docker/docker v27.0.3+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
+github.com/docker/docker v27.1.1+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/go-connections v0.4.0 h1:El9xVISelRB7BuFusrZozjnkIM5YnzCViNKohAFqRJQ=
 github.com/docker/go-connections v0.4.0/go.mod h1:Gbd7IOopHjR8Iph03tsViu4nIes5XhDvyHbTtUxmeec=
 github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4=
@@ -171,8 +171,8 @@ github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1m
 github.com/envoyproxy/go-control-plane v0.12.0 h1:4X+VP1GHd1Mhj6IB5mMeGbLCleqxjletLK6K0rbxyZI=
 github.com/envoyproxy/go-control-plane v0.12.0/go.mod h1:ZBTaoJ23lqITozF0M6G4/IragXCQKCnYbmlmtHvwRG0=
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
-github.com/envoyproxy/protoc-gen-validate v1.0.4 h1:gVPz/FMfvh57HdSJQyvBtF00j8JU4zdyUgIUNhlgg0A=
+github.com/envoyproxy/protoc-gen-validate v1.1.0 h1:tntQDh69XqOCOZsDz0lVJQez/2L6Uu2PdjCQwWCJ3bM=
-github.com/envoyproxy/protoc-gen-validate v1.0.4/go.mod h1:qys6tmnRsYrQqIhm2bvKZH4Blx/1gTIZ2UKVY1M+Yew=
+github.com/envoyproxy/protoc-gen-validate v1.1.0/go.mod h1:sXRDRVmzEbkM7CVcM06s9shE/m23dg3wzjl0UWqJ2q4=
 github.com/evanphx/json-patch v5.6.0+incompatible h1:jBYDEEiFBPxA0v50tFdvOzQQTCvpL6mnFh5mB2/l16U=
 github.com/evanphx/json-patch v5.6.0+incompatible/go.mod h1:50XU6AFN0ol/bzJsmQLiYLvXMP4fmwYFNcr97nuDLSk=
 github.com/facette/natsort v0.0.0-20181210072756-2cd4dd1e2dcb h1:IT4JYU7k4ikYg1SCxNI1/Tieq/NFvh6dzLdgi7eu0tM=
@@ -322,8 +322,8 @@ github.com/google/pprof v0.0.0-20200708004538-1a94d8640e99/go.mod h1:ZgVRPoUq/hf
 github.com/google/pprof v0.0.0-20240711041743-f6c9dda6c6da h1:xRmpO92tb8y+Z85iUOMOicpCfaYcv7o3Cg3wKrIpg8g=
 github.com/google/pprof v0.0.0-20240711041743-f6c9dda6c6da/go.mod h1:K1liHPHnj73Fdn/EKuT8nrFqBihUSKXoLYU0BuatOYo=
 github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
-github.com/google/s2a-go v0.1.7 h1:60BLSyTrOV4/haCDW4zb1guZItoSq8foHCXrAnjBo/o=
+github.com/google/s2a-go v0.1.8 h1:zZDs9gcbt9ZPLV0ndSyQk6Kacx2g/X+SKYovpnz3SMM=
-github.com/google/s2a-go v0.1.7/go.mod h1:50CgR4k1jNlWBu4UfS4AcfhVe1r6pdZPygJ3R8F0Qdw=
+github.com/google/s2a-go v0.1.8/go.mod h1:6iNWHTpQ+nfNRN5E00MSdfDwVesa8hhS32PhPO8deJA=
 github.com/google/uuid v1.0.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
@@ -332,8 +332,8 @@ github.com/googleapis/enterprise-certificate-proxy v0.3.2 h1:Vie5ybvEvT75RniqhfF
 github.com/googleapis/enterprise-certificate-proxy v0.3.2/go.mod h1:VLSiSSBs/ksPL8kq3OBOQ6WRI2QnaFynd1DCjZ62+V0=
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
-github.com/googleapis/gax-go/v2 v2.12.5 h1:8gw9KZK8TiVKB6q3zHY3SBzLnrGp6HQjyfYBYGmXdxA=
+github.com/googleapis/gax-go/v2 v2.13.0 h1:yitjD5f7jQHhyDsnhKEBU52NdvvdSeGzlAnDPT0hH1s=
-github.com/googleapis/gax-go/v2 v2.12.5/go.mod h1:BUDKcWo+RaKq5SC9vVYL0wLADa3VcfswbOMMRmB9H3E=
+github.com/googleapis/gax-go/v2 v2.13.0/go.mod h1:Z/fvTZXF8/uw7Xu5GuslPw+bplx6SS338j1Is2S+B7A=
 github.com/gophercloud/gophercloud v1.14.0 h1:Bt9zQDhPrbd4qX7EILGmy+i7GP35cc+AAL2+wIJpUE8=
 github.com/gophercloud/gophercloud v1.14.0/go.mod h1:aAVqcocTSXh2vYFZ1JTvx4EQmfgzxRcNupUfxZbBNDM=
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
@@ -353,8 +353,8 @@ github.com/grpc-ecosystem/grpc-gateway v1.16.0/go.mod h1:BDjrQk3hbvj6Nolgz8mAMFb
 github.com/grpc-ecosystem/grpc-gateway/v2 v2.20.0 h1:bkypFPDjIYGfCYD5mRBvpqxfYX1YCS1PXdKYWi8FsN0=
 github.com/grpc-ecosystem/grpc-gateway/v2 v2.20.0/go.mod h1:P+Lt/0by1T8bfcF3z737NnSbmxQAppXMRziHUxPOC8k=
 github.com/hashicorp/consul/api v1.3.0/go.mod h1:MmDNSzIMUjNpY/mQ398R4bk2FnqQLoPndWW5VkKPlCE=
-github.com/hashicorp/consul/api v1.29.2 h1:aYyRn8EdE2mSfG14S1+L9Qkjtz8RzmaWh6AcNGRNwPw=
+github.com/hashicorp/consul/api v1.29.4 h1:P6slzxDLBOxUSj3fWo2o65VuKtbtOXFi7TSSgtXutuE=
-github.com/hashicorp/consul/api v1.29.2/go.mod h1:0YObcaLNDSbtlgzIRtmRXI1ZkeuK0trCBxwZQ4MYnIk=
+github.com/hashicorp/consul/api v1.29.4/go.mod h1:HUlfw+l2Zy68ceJavv2zAyArl2fqhGWnMycyt56sBgg=
 github.com/hashicorp/consul/proto-public v0.6.2 h1:+DA/3g/IiKlJZb88NBn0ZgXrxJp2NlvCZdEyl+qxvL0=
 github.com/hashicorp/consul/proto-public v0.6.2/go.mod h1:cXXbOg74KBNGajC+o8RlA502Esf0R9prcoJgiOX/2Tg=
 github.com/hashicorp/consul/sdk v0.3.0/go.mod h1:VKf9jXwCTEY1QZP2MOLRhb5i/I/ssyNV1vwHyQBF0x8=
@@ -414,8 +414,8 @@ github.com/hashicorp/nomad/api v0.0.0-20240717122358-3d93bd3778f3/go.mod h1:svtx
 github.com/hashicorp/serf v0.8.2/go.mod h1:6hOLApaqBFA1NXqRQAsxw9QxuDEvNxSQRwA/JwenrHc=
 github.com/hashicorp/serf v0.10.1 h1:Z1H2J60yRKvfDYAOZLd2MU0ND4AH/WDz7xYHDWQsIPY=
 github.com/hashicorp/serf v0.10.1/go.mod h1:yL2t6BqATOLGc5HF7qbFkTfXoPIY0WZdWHfEvMqbG+4=
-github.com/hetznercloud/hcloud-go/v2 v2.12.0 h1:nOgfNTo0gyXZJJdM8mo/XH5MO/e80wAEpldRzdWayhY=
+github.com/hetznercloud/hcloud-go/v2 v2.13.1 h1:jq0GP4QaYE5d8xR/Zw17s9qoaESRJMXfGmtD1a/qckQ=
-github.com/hetznercloud/hcloud-go/v2 v2.12.0/go.mod h1:dhix40Br3fDiBhwaSG/zgaYOFFddpfBm/6R1Zz0IiF0=
+github.com/hetznercloud/hcloud-go/v2 v2.13.1/go.mod h1:dhix40Br3fDiBhwaSG/zgaYOFFddpfBm/6R1Zz0IiF0=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/hudl/fargo v1.3.0/go.mod h1:y3CKSmjA+wD2gak7sUSXTAoopbhU08POFhmITJgmKTg=
 github.com/ianlancetaylor/demangle v0.0.0-20181102032728-5e5cf60278f6/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
@@ -423,8 +423,8 @@ github.com/imdario/mergo v0.3.16 h1:wwQJbIsHYGMUyLSPrEq1CT16AhnhNJQ51+4fdHUnCl4=
 github.com/imdario/mergo v0.3.16/go.mod h1:WBLT9ZmE3lPoWsEzCh9LPo3TiwVN+ZKEjmz+hD27ysY=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
 github.com/influxdata/influxdb1-client v0.0.0-20191209144304-8bf82d3c094d/go.mod h1:qj24IKcXYK6Iy9ceXlo3Tc+vtHo9lIhSX5JddghvEPo=
-github.com/ionos-cloud/sdk-go/v6 v6.1.11 h1:J/uRN4UWO3wCyGOeDdMKv8LWRzKu6UIkLEaes38Kzh8=
+github.com/ionos-cloud/sdk-go/v6 v6.2.1 h1:mxxN+frNVmbFrmmFfXnBC3g2USYJrl6mc1LW2iNYbFY=
-github.com/ionos-cloud/sdk-go/v6 v6.1.11/go.mod h1:EzEgRIDxBELvfoa/uBN0kOQaqovLjUWEB7iW4/Q+t4k=
+github.com/ionos-cloud/sdk-go/v6 v6.2.1/go.mod h1:SXrO9OGyWjd2rZhAhEpdYN6VUAODzzqRdqA9BCviQtI=
 github.com/jarcoal/httpmock v1.3.1 h1:iUx3whfZWVf3jT01hQTO/Eo5sAYtB2/rqaUuOtpInww=
 github.com/jarcoal/httpmock v1.3.1/go.mod h1:3yb8rc4BI7TCBhFY8ng0gjuLKJNquuDNiPaZjnENuYg=
 github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
@@ -608,8 +608,8 @@ github.com/prometheus/client_golang v1.3.0/go.mod h1:hJaj2vgQTGQmVCsAACORcieXFeD
 github.com/prometheus/client_golang v1.4.0/go.mod h1:e9GMxYsXl05ICDXkRhurwBS4Q3OK1iX/F2sw+iXX5zU=
 github.com/prometheus/client_golang v1.7.1/go.mod h1:PY5Wy2awLA44sXw4AOSfFBetzPP4j5+D6mVACh+pe2M=
 github.com/prometheus/client_golang v1.11.0/go.mod h1:Z6t4BnS23TR94PD6BsDNk8yVqroYurpAkEiz0P2BEV0=
-github.com/prometheus/client_golang v1.19.1 h1:wZWJDwK+NameRJuPGDhlnFgx8e8HN3XHQeLaYJFJBOE=
+github.com/prometheus/client_golang v1.20.2 h1:5ctymQzZlyOON1666svgwn3s6IKWgfbjsejTMiXIyjg=
-github.com/prometheus/client_golang v1.19.1/go.mod h1:mP78NwGzrVks5S2H6ab8+ZZGJLZUq1hoULYBAYBw1Ho=
+github.com/prometheus/client_golang v1.20.2/go.mod h1:PIEt8X02hGcP8JWbeHyeZ53Y/jReSnHgO035n//V5WE=
 github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910/go.mod h1:MbSGuTsp3dbXC40dX6PRTWyKYBIrTGTE9sqQNg2J8bo=
 github.com/prometheus/client_model v0.0.0-20190115171406-56726106282f/go.mod h1:MbSGuTsp3dbXC40dX6PRTWyKYBIrTGTE9sqQNg2J8bo=
 github.com/prometheus/client_model v0.0.0-20190129233127-fd36f4220a90/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
@@ -625,8 +625,8 @@ github.com/prometheus/common v0.9.1/go.mod h1:yhUN8i9wzaXS3w1O07YhxHEBxD+W35wd8b
 github.com/prometheus/common v0.10.0/go.mod h1:Tlit/dnDKsSWFlCLTWaA1cyBgKHSMdTB80sz/V91rCo=
 github.com/prometheus/common v0.26.0/go.mod h1:M7rCNAaPfAosfx8veZJCuw84e35h3Cfd9VFqTh1DIvc=
 github.com/prometheus/common v0.29.0/go.mod h1:vu+V0TpY+O6vW9J44gczi3Ap/oXXR10b+M/gUGO4Hls=
-github.com/prometheus/common v0.55.0 h1:KEi6DK7lXW/m7Ig5i47x0vRzuBsHuvJdi5ee6Y3G1dc=
+github.com/prometheus/common v0.56.0 h1:UffReloqkBtvtQEYDg2s+uDPGRrJyC6vZWPGXf6OhPY=
-github.com/prometheus/common v0.55.0/go.mod h1:2SECS4xJG1kd8XF9IcM1gMX6510RAEL65zxzNImwdc8=
+github.com/prometheus/common v0.56.0/go.mod h1:7uRPFSUTbfZWsJ7MHY56sqt7hLQu3bxXHDnNhl8E9qI=
 github.com/prometheus/common/assets v0.2.0 h1:0P5OrzoHrYBOSM1OigWL3mY8ZvV2N4zIE/5AahrSrfM=
 github.com/prometheus/common/assets v0.2.0/go.mod h1:D17UVUE12bHbim7HzwUvtqm6gwBEaDQ0F+hIGbFbccI=
 github.com/prometheus/common/sigv4 v0.1.0 h1:qoVebwtwwEhS85Czm2dSROY5fTo2PAPEVdDeppTwGX4=
@@ -865,8 +865,8 @@ golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4Iltr
 golang.org/x/oauth2 v0.0.0-20191202225959-858c2ad4c8b6/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20210514164344-f6687ab2804c/go.mod h1:KelEdhl1UZF7XfJ4dDtk6s++YSgaE7mD/BuKKDLBl4A=
-golang.org/x/oauth2 v0.21.0 h1:tsimM75w1tF/uws5rbeHzIWxEqElMehnc+iW793zsZs=
+golang.org/x/oauth2 v0.22.0 h1:BzDx2FehcG7jJwgWLELCdmLuxk2i+x9UDpSiss2u0ZA=
-golang.org/x/oauth2 v0.21.0/go.mod h1:XYTD2NtWslqkgxebSiOHnXEap4TF09sJSc7H1sXbhtI=
+golang.org/x/oauth2 v0.22.0/go.mod h1:XYTD2NtWslqkgxebSiOHnXEap4TF09sJSc7H1sXbhtI=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -1047,8 +1047,8 @@ google.golang.org/api v0.20.0/go.mod h1:BwFmGc8tA3vsd7r/7kR8DY7iEEGSU04BFxCo5jP/
 google.golang.org/api v0.22.0/go.mod h1:BwFmGc8tA3vsd7r/7kR8DY7iEEGSU04BFxCo5jP/sfE=
 google.golang.org/api v0.24.0/go.mod h1:lIXQywCXRcnZPGlsd8NbLnOjtAoL6em04bJ9+z0MncE=
 google.golang.org/api v0.28.0/go.mod h1:lIXQywCXRcnZPGlsd8NbLnOjtAoL6em04bJ9+z0MncE=
-google.golang.org/api v0.189.0 h1:equMo30LypAkdkLMBqfeIqtyAnlyig1JSZArl4XPwdI=
+google.golang.org/api v0.190.0 h1:ASM+IhLY1zljNdLu19W1jTmU6A+gMk6M46Wlur61s+Q=
-google.golang.org/api v0.189.0/go.mod h1:FLWGJKb0hb+pU2j+rJqwbnsF+ym+fQs73rbJ+KAUgy8=
+google.golang.org/api v0.190.0/go.mod h1:QIr6I9iedBLnfqoD6L6Vze1UvS5Hzj5r2aUBOaZnLHo=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.2.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
@@ -1085,10 +1085,10 @@ google.golang.org/genproto v0.0.0-20200515170657-fc4c6c6a6587/go.mod h1:YsZOwe1m
 google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013/go.mod h1:NbSheEEYHJ7i3ixzK3sjbqSGDJWnxyFXZblF3eUsNvo=
 google.golang.org/genproto v0.0.0-20200618031413-b414f8b61790/go.mod h1:jDfRM7FcilCzHH/e9qn6dsT145K34l5v+OpcnNgKAAA=
 google.golang.org/genproto v0.0.0-20200825200019-8632dd797987/go.mod h1:FWY/as6DDZQgahTzZj3fqbO1CbirC29ZNUFHwi0/+no=
-google.golang.org/genproto/googleapis/api v0.0.0-20240711142825-46eb208f015d h1:kHjw/5UfflP/L5EbledDrcG4C2597RtymmGRZvHiCuY=
+google.golang.org/genproto/googleapis/api v0.0.0-20240725223205-93522f1f2a9f h1:b1Ln/PG8orm0SsBbHZWke8dDp2lrCD4jSmfglFpTZbk=
-google.golang.org/genproto/googleapis/api v0.0.0-20240711142825-46eb208f015d/go.mod h1:mw8MG/Qz5wfgYr6VqVCiZcHe/GJEfI+oGGDCohaVgB0=
+google.golang.org/genproto/googleapis/api v0.0.0-20240725223205-93522f1f2a9f/go.mod h1:AHT0dDg3SoMOgZGnZk29b5xTbPHMoEC8qthmBLJCpys=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20240722135656-d784300faade h1:oCRSWfwGXQsqlVdErcyTt4A93Y8fo0/9D4b1gnI++qo=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20240730163845-b1a4ccb954bf h1:liao9UHurZLtiEwBgT9LMOnKYsHze6eA6w1KQCMVN2Q=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20240722135656-d784300faade/go.mod h1:Ue6ibwXGpU+dqIcODieyLOcgj7z8+IcskoNIgZxtrFY=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20240730163845-b1a4ccb954bf/go.mod h1:Ue6ibwXGpU+dqIcODieyLOcgj7z8+IcskoNIgZxtrFY=
 google.golang.org/grpc v1.17.0/go.mod h1:6QZJwpn2B+Zp71q/5VxRsJ6NXXVCE5NRUHRo+f3cWCs=
 google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 google.golang.org/grpc v1.20.0/go.mod h1:chYK+tFQF0nDUGJgXMSgLCQk3phJEuONr2DCgLDdAQM=

model/exemplar/exemplar.go

@@ -15,7 +15,9 @@ package exemplar
 
 import "github.com/prometheus/prometheus/model/labels"
 
-// The combined length of the label names and values of an Exemplar's LabelSet MUST NOT exceed 128 UTF-8 characters
+// ExemplarMaxLabelSetLength is defined by OpenMetrics: "The combined length of
+// the label names and values of an Exemplar's LabelSet MUST NOT exceed 128
+// UTF-8 characters."
 // https://github.com/OpenObservability/OpenMetrics/blob/main/specification/OpenMetrics.md#exemplars
 const ExemplarMaxLabelSetLength = 128
 
@@ -49,7 +51,7 @@ func (e Exemplar) Equals(e2 Exemplar) bool {
 	return e.Value == e2.Value
 }
 
-// Sort first by timestamp, then value, then labels.
+// Compare first timestamps, then values, then labels.
 func Compare(a, b Exemplar) int {
 	if a.Ts < b.Ts {
 		return -1

model/labels/labels.go

@@ -315,7 +315,8 @@ func Compare(a, b Labels) int {
 	return len(a) - len(b)
 }
 
-// Copy labels from b on top of whatever was in ls previously, reusing memory or expanding if needed.
+// CopyFrom copies labels from b on top of whatever was in ls previously,
+// reusing memory or expanding if needed.
 func (ls *Labels) CopyFrom(b Labels) {
 	(*ls) = append((*ls)[:0], b...)
 }
@@ -422,7 +423,7 @@ type ScratchBuilder struct {
 	add Labels
 }
 
-// Symbol-table is no-op, just for api parity with dedupelabels.
+// SymbolTable is no-op, just for api parity with dedupelabels.
 type SymbolTable struct{}
 
 func NewSymbolTable() *SymbolTable { return nil }
@@ -458,7 +459,7 @@ func (b *ScratchBuilder) Add(name, value string) {
 	b.add = append(b.add, Label{Name: name, Value: value})
 }
 
-// Add a name/value pair, using []byte instead of string.
+// UnsafeAddBytes adds a name/value pair, using []byte instead of string.
 // The '-tags stringlabels' version of this function is unsafe, hence the name.
 // This version is safe - it copies the strings immediately - but we keep the same name so everything compiles.
 func (b *ScratchBuilder) UnsafeAddBytes(name, value []byte) {
@@ -475,14 +476,14 @@ func (b *ScratchBuilder) Assign(ls Labels) {
 	b.add = append(b.add[:0], ls...) // Copy on top of our slice, so we don't retain the input slice.
 }
 
-// Return the name/value pairs added so far as a Labels object.
+// Labels returns the name/value pairs added so far as a Labels object.
 // Note: if you want them sorted, call Sort() first.
 func (b *ScratchBuilder) Labels() Labels {
 	// Copy the slice, so the next use of ScratchBuilder doesn't overwrite.
 	return append([]Label{}, b.add...)
 }
 
-// Write the newly-built Labels out to ls.
+// Overwrite the newly-built Labels out to ls.
 // Callers must ensure that there are no other references to ls, or any strings fetched from it.
 func (b *ScratchBuilder) Overwrite(ls *Labels) {
 	*ls = append((*ls)[:0], b.add...)

model/labels/labels_common.go

@@ -95,12 +95,23 @@ func (ls *Labels) UnmarshalYAML(unmarshal func(interface{}) error) error {
 }
 
 // IsValid checks if the metric name or label names are valid.
-func (ls Labels) IsValid() bool {
+func (ls Labels) IsValid(validationScheme model.ValidationScheme) bool {
 	err := ls.Validate(func(l Label) error {
-		if l.Name == model.MetricNameLabel && !model.IsValidMetricName(model.LabelValue(l.Value)) {
+		if l.Name == model.MetricNameLabel {
+			// If the default validation scheme has been overridden with legacy mode,
+			// we need to call the special legacy validation checker.
+			if validationScheme == model.LegacyValidation && model.NameValidationScheme == model.UTF8Validation && !model.IsValidLegacyMetricName(string(model.LabelValue(l.Value))) {
 				return strconv.ErrSyntax
 			}
-		if !model.LabelName(l.Name).IsValid() || !model.LabelValue(l.Value).IsValid() {
+			if !model.IsValidMetricName(model.LabelValue(l.Value)) {
+				return strconv.ErrSyntax
+			}
+		}
+		if validationScheme == model.LegacyValidation && model.NameValidationScheme == model.UTF8Validation {
+			if !model.LabelName(l.Name).IsValidLegacy() || !model.LabelValue(l.Value).IsValid() {
+				return strconv.ErrSyntax
+			}
+		} else if !model.LabelName(l.Name).IsValid() || !model.LabelValue(l.Value).IsValid() {
 			return strconv.ErrSyntax
 		}
 		return nil

model/labels/labels_test.go

@@ -21,6 +21,7 @@ import (
 	"strings"
 	"testing"
 
+	"github.com/prometheus/common/model"
 	"github.com/stretchr/testify/require"
 	"gopkg.in/yaml.v2"
 )
@@ -272,11 +273,86 @@ func TestLabels_IsValid(t *testing.T) {
 		},
 	} {
 		t.Run("", func(t *testing.T) {
-			require.Equal(t, test.expected, test.input.IsValid())
+			require.Equal(t, test.expected, test.input.IsValid(model.LegacyValidation))
 		})
 	}
 }
 
+func TestLabels_ValidationModes(t *testing.T) {
+	for _, test := range []struct {
+		input      Labels
+		globalMode model.ValidationScheme
+		callMode   model.ValidationScheme
+		expected   bool
+	}{
+		{
+			input: FromStrings(
+				"__name__", "test.metric",
+				"hostname", "localhost",
+				"job", "check",
+			),
+			globalMode: model.UTF8Validation,
+			callMode:   model.UTF8Validation,
+			expected:   true,
+		},
+		{
+			input: FromStrings(
+				"__name__", "test",
+				"\xc5 bad utf8", "localhost",
+				"job", "check",
+			),
+			globalMode: model.UTF8Validation,
+			callMode:   model.UTF8Validation,
+			expected:   false,
+		},
+		{
+			// Setting the common model to legacy validation and then trying to check for UTF-8 on a
+			// per-call basis is not supported.
+			input: FromStrings(
+				"__name__", "test.utf8.metric",
+				"hostname", "localhost",
+				"job", "check",
+			),
+			globalMode: model.LegacyValidation,
+			callMode:   model.UTF8Validation,
+			expected:   false,
+		},
+		{
+			input: FromStrings(
+				"__name__", "test",
+				"hostname", "localhost",
+				"job", "check",
+			),
+			globalMode: model.LegacyValidation,
+			callMode:   model.LegacyValidation,
+			expected:   true,
+		},
+		{
+			input: FromStrings(
+				"__name__", "test.utf8.metric",
+				"hostname", "localhost",
+				"job", "check",
+			),
+			globalMode: model.UTF8Validation,
+			callMode:   model.LegacyValidation,
+			expected:   false,
+		},
+		{
+			input: FromStrings(
+				"__name__", "test",
+				"host.name", "localhost",
+				"job", "check",
+			),
+			globalMode: model.UTF8Validation,
+			callMode:   model.LegacyValidation,
+			expected:   false,
+		},
+	} {
+		model.NameValidationScheme = test.globalMode
+		require.Equal(t, test.expected, test.input.IsValid(test.callMode))
+	}
+}
+
 func TestLabels_Equal(t *testing.T) {
 	labels := FromStrings(
 		"aaa", "111",

model/textparse/interface.go

@@ -106,8 +106,8 @@ const (
 	EntryInvalid   Entry = -1
 	EntryType      Entry = 0
 	EntryHelp      Entry = 1
-	EntrySeries    Entry = 2 // A series with a simple float64 as value.
+	EntrySeries    Entry = 2 // EntrySeries marks a series with a simple float64 as value.
 	EntryComment   Entry = 3
 	EntryUnit      Entry = 4
-	EntryHistogram Entry = 5 // A series with a native histogram as a value.
+	EntryHistogram Entry = 5 // EntryHistogram marks a series with a native histogram as a value.
 )

model/textparse/openmetricsparse.go

@@ -94,14 +94,44 @@ type OpenMetricsParser struct {
 	exemplarVal   float64
 	exemplarTs    int64
 	hasExemplarTs bool
+
+	skipCTSeries bool
 }
 
-// NewOpenMetricsParser returns a new parser of the byte slice.
+type openMetricsParserOptions struct {
-func NewOpenMetricsParser(b []byte, st *labels.SymbolTable) Parser {
+	SkipCTSeries bool
-	return &OpenMetricsParser{
+}
+
+type OpenMetricsOption func(*openMetricsParserOptions)
+
+// WithOMParserCTSeriesSkipped turns off exposing _created lines
+// as series, which makes those only used for parsing created timestamp
+// for `CreatedTimestamp` method purposes.
+//
+// It's recommended to use this option to avoid using _created lines for other
+// purposes than created timestamp, but leave false by default for the
+// best-effort compatibility.
+func WithOMParserCTSeriesSkipped() OpenMetricsOption {
+	return func(o *openMetricsParserOptions) {
+		o.SkipCTSeries = true
+	}
+}
+
+// NewOpenMetricsParser returns a new parser for the byte slice with option to skip CT series parsing.
+func NewOpenMetricsParser(b []byte, st *labels.SymbolTable, opts ...OpenMetricsOption) Parser {
+	options := &openMetricsParserOptions{}
+
+	for _, opt := range opts {
+		opt(options)
+	}
+
+	parser := &OpenMetricsParser{
 		l:            &openMetricsLexer{b: b},
 		builder:      labels.NewScratchBuilderWithSymbolTable(st, 16),
+		skipCTSeries: options.SkipCTSeries,
 	}
+
+	return parser
 }
 
 // Series returns the bytes of the series, the timestamp if set, and the value
@@ -219,10 +249,90 @@ func (p *OpenMetricsParser) Exemplar(e *exemplar.Exemplar) bool {
 	return true
 }
 
-// CreatedTimestamp returns nil as it's not implemented yet.
+// CreatedTimestamp returns the created timestamp for a current Metric if exists or nil.
-// TODO(bwplotka): https://github.com/prometheus/prometheus/issues/12980
+// NOTE(Maniktherana): Might use additional CPU/mem resources due to deep copy of parser required for peeking given 1.0 OM specification on _created series.
 func (p *OpenMetricsParser) CreatedTimestamp() *int64 {
+	if !TypeRequiresCT(p.mtype) {
+		// Not a CT supported metric type, fast path.
 		return nil
+	}
+
+	var (
+		currLset                labels.Labels
+		buf                     []byte
+		peekWithoutNameLsetHash uint64
+	)
+	p.Metric(&currLset)
+	currFamilyLsetHash, buf := currLset.HashWithoutLabels(buf, labels.MetricName, "le", "quantile")
+	// Search for the _created line for the currFamilyLsetHash using ephemeral parser until
+	// we see EOF or new metric family. We have to do it as we don't know where (and if)
+	// that CT line is.
+	// TODO(bwplotka): Make sure OM 1.1/2.0 pass CT via metadata or exemplar-like to avoid this.
+	peek := deepCopy(p)
+	for {
+		eType, err := peek.Next()
+		if err != nil {
+			// This means peek will give error too later on, so def no CT line found.
+			// This might result in partial scrape with wrong/missing CT, but only
+			// spec improvement would help.
+			// TODO(bwplotka): Make sure OM 1.1/2.0 pass CT via metadata or exemplar-like to avoid this.
+			return nil
+		}
+		if eType != EntrySeries {
+			// Assume we hit different family, no CT line found.
+			return nil
+		}
+
+		var peekedLset labels.Labels
+		peek.Metric(&peekedLset)
+		peekedName := peekedLset.Get(model.MetricNameLabel)
+		if !strings.HasSuffix(peekedName, "_created") {
+			// Not a CT line, search more.
+			continue
+		}
+
+		// We got a CT line here, but let's search if CT line is actually for our series, edge case.
+		peekWithoutNameLsetHash, _ = peekedLset.HashWithoutLabels(buf, labels.MetricName, "le", "quantile")
+		if peekWithoutNameLsetHash != currFamilyLsetHash {
+			// CT line for a different series, for our series no CT.
+			return nil
+		}
+		ct := int64(peek.val)
+		return &ct
+	}
+}
+
+// TypeRequiresCT returns true if the metric type requires a _created timestamp.
+func TypeRequiresCT(t model.MetricType) bool {
+	switch t {
+	case model.MetricTypeCounter, model.MetricTypeSummary, model.MetricTypeHistogram:
+		return true
+	default:
+		return false
+	}
+}
+
+// deepCopy creates a copy of a parser without re-using the slices' original memory addresses.
+func deepCopy(p *OpenMetricsParser) OpenMetricsParser {
+	newB := make([]byte, len(p.l.b))
+	copy(newB, p.l.b)
+
+	newLexer := &openMetricsLexer{
+		b:     newB,
+		i:     p.l.i,
+		start: p.l.start,
+		err:   p.l.err,
+		state: p.l.state,
+	}
+
+	newParser := OpenMetricsParser{
+		l:            newLexer,
+		builder:      p.builder,
+		mtype:        p.mtype,
+		val:          p.val,
+		skipCTSeries: false,
+	}
+	return newParser
 }
 
 // nextToken returns the next token from the openMetricsLexer.
@@ -337,7 +447,13 @@ func (p *OpenMetricsParser) Next() (Entry, error) {
 		}
 
 		p.series = p.l.b[p.start:p.l.i]
-		return p.parseMetricSuffix(p.nextToken())
+		if err := p.parseSeriesEndOfLine(p.nextToken()); err != nil {
+			return EntryInvalid, err
+		}
+		if p.skipCTSeries && p.isCreatedSeries() {
+			return p.Next()
+		}
+		return EntrySeries, nil
 	case tMName:
 		p.offsets = append(p.offsets, p.start, p.l.i)
 		p.series = p.l.b[p.start:p.l.i]
@@ -351,8 +467,14 @@ func (p *OpenMetricsParser) Next() (Entry, error) {
 			p.series = p.l.b[p.start:p.l.i]
 			t2 = p.nextToken()
 		}
-		return p.parseMetricSuffix(t2)
 
+		if err := p.parseSeriesEndOfLine(t2); err != nil {
+			return EntryInvalid, err
+		}
+		if p.skipCTSeries && p.isCreatedSeries() {
+			return p.Next()
+		}
+		return EntrySeries, nil
 	default:
 		err = p.parseError("expected a valid start token", t)
 	}
@@ -467,51 +589,64 @@ func (p *OpenMetricsParser) parseLVals(offsets []int, isExemplar bool) ([]int, e
 	}
 }
 
-// parseMetricSuffix parses the end of the line after the metric name and
+// isCreatedSeries returns true if the current series is a _created series.
-// labels. It starts parsing with the provided token.
+func (p *OpenMetricsParser) isCreatedSeries() bool {
-func (p *OpenMetricsParser) parseMetricSuffix(t token) (Entry, error) {
+	var newLbs labels.Labels
+	p.Metric(&newLbs)
+	name := newLbs.Get(model.MetricNameLabel)
+	if TypeRequiresCT(p.mtype) && strings.HasSuffix(name, "_created") {
+		return true
+	}
+	return false
+}
+
+// parseSeriesEndOfLine parses the series end of the line (value, optional
+// timestamp, commentary, etc.) after the metric name and labels.
+// It starts parsing with the provided token.
+func (p *OpenMetricsParser) parseSeriesEndOfLine(t token) error {
 	if p.offsets[0] == -1 {
-		return EntryInvalid, fmt.Errorf("metric name not set while parsing: %q", p.l.b[p.start:p.l.i])
+		return fmt.Errorf("metric name not set while parsing: %q", p.l.b[p.start:p.l.i])
 	}
 
 	var err error
 	p.val, err = p.getFloatValue(t, "metric")
 	if err != nil {
-		return EntryInvalid, err
+		return err
 	}
 
 	p.hasTS = false
 	switch t2 := p.nextToken(); t2 {
 	case tEOF:
-		return EntryInvalid, errors.New("data does not end with # EOF")
+		return errors.New("data does not end with # EOF")
 	case tLinebreak:
 		break
 	case tComment:
 		if err := p.parseComment(); err != nil {
-			return EntryInvalid, err
+			return err
 		}
 	case tTimestamp:
 		p.hasTS = true
 		var ts float64
 		// A float is enough to hold what we need for millisecond resolution.
 		if ts, err = parseFloat(yoloString(p.l.buf()[1:])); err != nil {
-			return EntryInvalid, fmt.Errorf("%w while parsing: %q", err, p.l.b[p.start:p.l.i])
+			return fmt.Errorf("%w while parsing: %q", err, p.l.b[p.start:p.l.i])
 		}
 		if math.IsNaN(ts) || math.IsInf(ts, 0) {
-			return EntryInvalid, fmt.Errorf("invalid timestamp %f", ts)
+			return fmt.Errorf("invalid timestamp %f", ts)
 		}
 		p.ts = int64(ts * 1000)
 		switch t3 := p.nextToken(); t3 {
 		case tLinebreak:
 		case tComment:
 			if err := p.parseComment(); err != nil {
-				return EntryInvalid, err
+				return err
 			}
 		default:
-			return EntryInvalid, p.parseError("expected next entry after timestamp", t3)
+			return p.parseError("expected next entry after timestamp", t3)
 		}
 	}
-	return EntrySeries, nil
+
+	return nil
 }
 
 func (p *OpenMetricsParser) getFloatValue(t token, after string) (float64, error) {

model/textparse/openmetricsparse_test.go

@@ -14,6 +14,7 @@
 package textparse
 
 import (
+	"errors"
 	"io"
 	"testing"
 
@@ -24,6 +25,8 @@ import (
 	"github.com/prometheus/prometheus/model/labels"
 )
 
+func int64p(x int64) *int64 { return &x }
+
 func TestOpenMetricsParse(t *testing.T) {
 	input := `# HELP go_gc_duration_seconds A summary of the GC invocation durations.
 # TYPE go_gc_duration_seconds summary
@@ -63,15 +66,34 @@ ss{A="a"} 0
 _metric_starting_with_underscore 1
 testmetric{_label_starting_with_underscore="foo"} 1
 testmetric{label="\"bar\""} 1
+# HELP foo Counter with and without labels to certify CT is parsed for both cases
 # TYPE foo counter
-foo_total 17.0 1520879607.789 # {id="counter-test"} 5`
+foo_total 17.0 1520879607.789 # {id="counter-test"} 5
+foo_created 1000
+foo_total{a="b"} 17.0 1520879607.789 # {id="counter-test"} 5
+foo_created{a="b"} 1000
+# HELP bar Summary with CT at the end, making sure we find CT even if it's multiple lines a far
+# TYPE bar summary
+bar_count 17.0
+bar_sum 324789.3
+bar{quantile="0.95"} 123.7
+bar{quantile="0.99"} 150.0
+bar_created 1520430000
+# HELP baz Histogram with the same objective as above's summary
+# TYPE baz histogram
+baz_bucket{le="0.0"} 0
+baz_bucket{le="+Inf"} 17
+baz_count 17
+baz_sum 324789.3
+baz_created 1520430000
+# HELP fizz_created Gauge which shouldn't be parsed as CT
+# TYPE fizz_created gauge
+fizz_created 17.0`
 
 	input += "\n# HELP metric foo\x00bar"
 	input += "\nnull_byte_metric{a=\"abc\x00\"} 1"
 	input += "\n# EOF\n"
 
-	int64p := func(x int64) *int64 { return &x }
-
 	exp := []expectedParse{
 		{
 			m:    "go_gc_duration_seconds",
@@ -216,6 +238,9 @@ foo_total 17.0 1520879607.789 # {id="counter-test"} 5`
 			m:    "testmetric{label=\"\\\"bar\\\"\"}",
 			v:    1,
 			lset: labels.FromStrings("__name__", "testmetric", "label", `"bar"`),
+		}, {
+			m:    "foo",
+			help: "Counter with and without labels to certify CT is parsed for both cases",
 		}, {
 			m:   "foo",
 			typ: model.MetricTypeCounter,
@@ -225,6 +250,76 @@ foo_total 17.0 1520879607.789 # {id="counter-test"} 5`
 			lset: labels.FromStrings("__name__", "foo_total"),
 			t:    int64p(1520879607789),
 			e:    &exemplar.Exemplar{Labels: labels.FromStrings("id", "counter-test"), Value: 5},
+			ct:   int64p(1000),
+		}, {
+			m:    `foo_total{a="b"}`,
+			v:    17.0,
+			lset: labels.FromStrings("__name__", "foo_total", "a", "b"),
+			t:    int64p(1520879607789),
+			e:    &exemplar.Exemplar{Labels: labels.FromStrings("id", "counter-test"), Value: 5},
+			ct:   int64p(1000),
+		}, {
+			m:    "bar",
+			help: "Summary with CT at the end, making sure we find CT even if it's multiple lines a far",
+		}, {
+			m:   "bar",
+			typ: model.MetricTypeSummary,
+		}, {
+			m:    "bar_count",
+			v:    17.0,
+			lset: labels.FromStrings("__name__", "bar_count"),
+			ct:   int64p(1520430000),
+		}, {
+			m:    "bar_sum",
+			v:    324789.3,
+			lset: labels.FromStrings("__name__", "bar_sum"),
+			ct:   int64p(1520430000),
+		}, {
+			m:    `bar{quantile="0.95"}`,
+			v:    123.7,
+			lset: labels.FromStrings("__name__", "bar", "quantile", "0.95"),
+			ct:   int64p(1520430000),
+		}, {
+			m:    `bar{quantile="0.99"}`,
+			v:    150.0,
+			lset: labels.FromStrings("__name__", "bar", "quantile", "0.99"),
+			ct:   int64p(1520430000),
+		}, {
+			m:    "baz",
+			help: "Histogram with the same objective as above's summary",
+		}, {
+			m:   "baz",
+			typ: model.MetricTypeHistogram,
+		}, {
+			m:    `baz_bucket{le="0.0"}`,
+			v:    0,
+			lset: labels.FromStrings("__name__", "baz_bucket", "le", "0.0"),
+			ct:   int64p(1520430000),
+		}, {
+			m:    `baz_bucket{le="+Inf"}`,
+			v:    17,
+			lset: labels.FromStrings("__name__", "baz_bucket", "le", "+Inf"),
+			ct:   int64p(1520430000),
+		}, {
+			m:    `baz_count`,
+			v:    17,
+			lset: labels.FromStrings("__name__", "baz_count"),
+			ct:   int64p(1520430000),
+		}, {
+			m:    `baz_sum`,
+			v:    324789.3,
+			lset: labels.FromStrings("__name__", "baz_sum"),
+			ct:   int64p(1520430000),
+		}, {
+			m:    "fizz_created",
+			help: "Gauge which shouldn't be parsed as CT",
+		}, {
+			m:   "fizz_created",
+			typ: model.MetricTypeGauge,
+		}, {
+			m:    `fizz_created`,
+			v:    17,
+			lset: labels.FromStrings("__name__", "fizz_created"),
 		}, {
 			m:    "metric",
 			help: "foo\x00bar",
@@ -235,8 +330,8 @@ foo_total 17.0 1520879607.789 # {id="counter-test"} 5`
 		},
 	}
 
-	p := NewOpenMetricsParser([]byte(input), labels.NewSymbolTable())
+	p := NewOpenMetricsParser([]byte(input), labels.NewSymbolTable(), WithOMParserCTSeriesSkipped())
-	checkParseResults(t, p, exp)
+	checkParseResultsWithCT(t, p, exp, true)
 }
 
 func TestUTF8OpenMetricsParse(t *testing.T) {
@@ -251,6 +346,7 @@ func TestUTF8OpenMetricsParse(t *testing.T) {
 # UNIT "go.gc_duration_seconds" seconds
 {"go.gc_duration_seconds",quantile="0"} 4.9351e-05
 {"go.gc_duration_seconds",quantile="0.25"} 7.424100000000001e-05
+{"go.gc_duration_seconds_created"} 12313
 {"go.gc_duration_seconds",quantile="0.5",a="b"} 8.3835e-05
 {"http.status",q="0.9",a="b"} 8.3835e-05
 {"http.status",q="0.9",a="b"} 8.3835e-05
@@ -274,10 +370,12 @@ func TestUTF8OpenMetricsParse(t *testing.T) {
 			m:    `{"go.gc_duration_seconds",quantile="0"}`,
 			v:    4.9351e-05,
 			lset: labels.FromStrings("__name__", "go.gc_duration_seconds", "quantile", "0"),
+			ct:   int64p(12313),
 		}, {
 			m:    `{"go.gc_duration_seconds",quantile="0.25"}`,
 			v:    7.424100000000001e-05,
 			lset: labels.FromStrings("__name__", "go.gc_duration_seconds", "quantile", "0.25"),
+			ct:   int64p(12313),
 		}, {
 			m:    `{"go.gc_duration_seconds",quantile="0.5",a="b"}`,
 			v:    8.3835e-05,
@@ -306,8 +404,8 @@ choices}`, "strange©™\n'quoted' \"name\"", "6"),
 		},
 	}
 
-	p := NewOpenMetricsParser([]byte(input), labels.NewSymbolTable())
+	p := NewOpenMetricsParser([]byte(input), labels.NewSymbolTable(), WithOMParserCTSeriesSkipped())
-	checkParseResults(t, p, exp)
+	checkParseResultsWithCT(t, p, exp, true)
 }
 
 func TestOpenMetricsParseErrors(t *testing.T) {
@@ -598,10 +696,6 @@ func TestOpenMetricsParseErrors(t *testing.T) {
 			input: "# TYPE hhh histogram\nhhh_bucket{le=\"+Inf\"} 1 # {aa=\"bb\"} 4 -Inf",
 			err:   `invalid exemplar timestamp -Inf`,
 		},
-		{
-			input: "# TYPE hhh histogram\nhhh_bucket{le=\"+Inf\"} 1 # {aa=\"bb\"} 4 Inf",
-			err:   `invalid exemplar timestamp +Inf`,
-		},
 	}
 
 	for i, c := range cases {
@@ -684,3 +778,217 @@ func TestOMNullByteHandling(t *testing.T) {
 		require.Equal(t, c.err, err.Error(), "test %d", i)
 	}
 }
+
+// While not desirable, there are cases were CT fails to parse and
+// these tests show them.
+// TODO(maniktherana): Make sure OM 1.1/2.0 pass CT via metadata or exemplar-like to avoid this.
+func TestCTParseFailures(t *testing.T) {
+	input := `# HELP something Histogram with _created between buckets and summary
+# TYPE something histogram
+something_count 17
+something_sum 324789.3
+something_created 1520430001
+something_bucket{le="0.0"} 0
+something_bucket{le="+Inf"} 17
+# HELP thing Histogram with _created as first line
+# TYPE thing histogram
+thing_created 1520430002
+thing_count 17
+thing_sum 324789.3
+thing_bucket{le="0.0"} 0
+thing_bucket{le="+Inf"} 17
+# HELP yum Summary with _created between sum and quantiles
+# TYPE yum summary
+yum_count 17.0
+yum_sum 324789.3
+yum_created 1520430003
+yum{quantile="0.95"} 123.7
+yum{quantile="0.99"} 150.0
+# HELP foobar Summary with _created as the first line
+# TYPE foobar summary
+foobar_created 1520430004
+foobar_count 17.0
+foobar_sum 324789.3
+foobar{quantile="0.95"} 123.7
+foobar{quantile="0.99"} 150.0`
+
+	input += "\n# EOF\n"
+
+	int64p := func(x int64) *int64 { return &x }
+
+	type expectCT struct {
+		m     string
+		ct    *int64
+		typ   model.MetricType
+		help  string
+		isErr bool
+	}
+
+	exp := []expectCT{
+		{
+			m:     "something",
+			help:  "Histogram with _created between buckets and summary",
+			isErr: false,
+		}, {
+			m:     "something",
+			typ:   model.MetricTypeHistogram,
+			isErr: false,
+		}, {
+			m:     `something_count`,
+			ct:    int64p(1520430001),
+			isErr: false,
+		}, {
+			m:     `something_sum`,
+			ct:    int64p(1520430001),
+			isErr: false,
+		}, {
+			m:     `something_bucket{le="0.0"}`,
+			ct:    int64p(1520430001),
+			isErr: true,
+		}, {
+			m:     `something_bucket{le="+Inf"}`,
+			ct:    int64p(1520430001),
+			isErr: true,
+		}, {
+			m:     "thing",
+			help:  "Histogram with _created as first line",
+			isErr: false,
+		}, {
+			m:     "thing",
+			typ:   model.MetricTypeHistogram,
+			isErr: false,
+		}, {
+			m:     `thing_count`,
+			ct:    int64p(1520430002),
+			isErr: true,
+		}, {
+			m:     `thing_sum`,
+			ct:    int64p(1520430002),
+			isErr: true,
+		}, {
+			m:     `thing_bucket{le="0.0"}`,
+			ct:    int64p(1520430002),
+			isErr: true,
+		}, {
+			m:     `thing_bucket{le="+Inf"}`,
+			ct:    int64p(1520430002),
+			isErr: true,
+		}, {
+			m:     "yum",
+			help:  "Summary with _created between summary and quantiles",
+			isErr: false,
+		}, {
+			m:     "yum",
+			typ:   model.MetricTypeSummary,
+			isErr: false,
+		}, {
+			m:     "yum_count",
+			ct:    int64p(1520430003),
+			isErr: false,
+		}, {
+			m:     "yum_sum",
+			ct:    int64p(1520430003),
+			isErr: false,
+		}, {
+			m:     `yum{quantile="0.95"}`,
+			ct:    int64p(1520430003),
+			isErr: true,
+		}, {
+			m:     `yum{quantile="0.99"}`,
+			ct:    int64p(1520430003),
+			isErr: true,
+		}, {
+			m:     "foobar",
+			help:  "Summary with _created as the first line",
+			isErr: false,
+		}, {
+			m:     "foobar",
+			typ:   model.MetricTypeSummary,
+			isErr: false,
+		}, {
+			m:     "foobar_count",
+			ct:    int64p(1520430004),
+			isErr: true,
+		}, {
+			m:     "foobar_sum",
+			ct:    int64p(1520430004),
+			isErr: true,
+		}, {
+			m:     `foobar{quantile="0.95"}`,
+			ct:    int64p(1520430004),
+			isErr: true,
+		}, {
+			m:     `foobar{quantile="0.99"}`,
+			ct:    int64p(1520430004),
+			isErr: true,
+		},
+	}
+
+	p := NewOpenMetricsParser([]byte(input), labels.NewSymbolTable(), WithOMParserCTSeriesSkipped())
+	i := 0
+
+	var res labels.Labels
+	for {
+		et, err := p.Next()
+		if errors.Is(err, io.EOF) {
+			break
+		}
+		require.NoError(t, err)
+
+		switch et {
+		case EntrySeries:
+			p.Metric(&res)
+
+			if ct := p.CreatedTimestamp(); exp[i].isErr {
+				require.Nil(t, ct)
+			} else {
+				require.Equal(t, *exp[i].ct, *ct)
+			}
+		default:
+			i++
+			continue
+		}
+		i++
+	}
+}
+
+func TestDeepCopy(t *testing.T) {
+	input := []byte(`# HELP go_goroutines A gauge goroutines.
+# TYPE go_goroutines gauge
+go_goroutines 33 123.123
+# TYPE go_gc_duration_seconds summary
+go_gc_duration_seconds
+go_gc_duration_seconds_created`)
+
+	st := labels.NewSymbolTable()
+	parser := NewOpenMetricsParser(input, st, WithOMParserCTSeriesSkipped()).(*OpenMetricsParser)
+
+	// Modify the original parser state
+	_, err := parser.Next()
+	require.NoError(t, err)
+	require.Equal(t, "go_goroutines", string(parser.l.b[parser.offsets[0]:parser.offsets[1]]))
+	require.True(t, parser.skipCTSeries)
+
+	// Create a deep copy of the parser
+	copyParser := deepCopy(parser)
+	etype, err := copyParser.Next()
+	require.NoError(t, err)
+	require.Equal(t, EntryType, etype)
+	require.True(t, parser.skipCTSeries)
+	require.False(t, copyParser.skipCTSeries)
+
+	// Modify the original parser further
+	parser.Next()
+	parser.Next()
+	parser.Next()
+	require.Equal(t, "go_gc_duration_seconds", string(parser.l.b[parser.offsets[0]:parser.offsets[1]]))
+	require.Equal(t, "summary", string(parser.mtype))
+	require.False(t, copyParser.skipCTSeries)
+	require.True(t, parser.skipCTSeries)
+
+	// Ensure the copy remains unchanged
+	copyParser.Next()
+	copyParser.Next()
+	require.Equal(t, "go_gc_duration_seconds", string(copyParser.l.b[copyParser.offsets[0]:copyParser.offsets[1]]))
+	require.False(t, copyParser.skipCTSeries)
+}

model/textparse/promparse_test.go

@@ -18,6 +18,7 @@ import (
 	"errors"
 	"io"
 	"os"
+	"strings"
 	"testing"
 
 	"github.com/klauspost/compress/gzip"
@@ -41,6 +42,7 @@ type expectedParse struct {
 	unit    string
 	comment string
 	e       *exemplar.Exemplar
+	ct      *int64
 }
 
 func TestPromParse(t *testing.T) {
@@ -188,6 +190,10 @@ testmetric{label="\"bar\""} 1`
 }
 
 func checkParseResults(t *testing.T, p Parser, exp []expectedParse) {
+	checkParseResultsWithCT(t, p, exp, false)
+}
+
+func checkParseResultsWithCT(t *testing.T, p Parser, exp []expectedParse, ctLinesRemoved bool) {
 	i := 0
 
 	var res labels.Labels
@@ -205,6 +211,14 @@ func checkParseResults(t *testing.T, p Parser, exp []expectedParse) {
 
 			p.Metric(&res)
 
+			if ctLinesRemoved {
+				// Are CT series skipped?
+				_, typ := p.Type()
+				if TypeRequiresCT(typ) && strings.HasSuffix(res.Get(labels.MetricName), "_created") {
+					t.Fatalf("we exped created lines skipped")
+				}
+			}
+
 			require.Equal(t, exp[i].m, string(m))
 			require.Equal(t, exp[i].t, ts)
 			require.Equal(t, exp[i].v, v)
@@ -218,6 +232,11 @@ func checkParseResults(t *testing.T, p Parser, exp []expectedParse) {
 				require.True(t, found)
 				testutil.RequireEqual(t, *exp[i].e, e)
 			}
+			if ct := p.CreatedTimestamp(); ct != nil {
+				require.Equal(t, *exp[i].ct, *ct)
+			} else {
+				require.Nil(t, exp[i].ct)
+			}
 
 		case EntryType:
 			m, typ := p.Type()
@@ -476,7 +495,9 @@ const (
 func BenchmarkParse(b *testing.B) {
 	for parserName, parser := range map[string]func([]byte, *labels.SymbolTable) Parser{
 		"prometheus": NewPromParser,
-		"openmetrics": NewOpenMetricsParser,
+		"openmetrics": func(b []byte, st *labels.SymbolTable) Parser {
+			return NewOpenMetricsParser(b, st)
+		},
 	} {
 		for _, fn := range []string{"promtestdata.txt", "promtestdata.nometa.txt"} {
 			f, err := os.Open(fn)

model/textparse/protobufparse.go

@@ -47,7 +47,7 @@ import (
 // the re-arrangement work is actually causing problems (which has to be seen),
 // that expectation needs to be changed.
 type ProtobufParser struct {
-	in        []byte // The intput to parse.
+	in        []byte // The input to parse.
 	inPos     int    // Position within the input.
 	metricPos int    // Position within Metric slice.
 	// fieldPos is the position within a Summary or (legacy) Histogram. -2
@@ -71,7 +71,7 @@ type ProtobufParser struct {
 
 	mf *dto.MetricFamily
 
-	// Wether to also parse a classic histogram that is also present as a
+	// Whether to also parse a classic histogram that is also present as a
 	// native histogram.
 	parseClassicHistograms bool
 
@@ -409,6 +409,7 @@ func (p *ProtobufParser) Next() (Entry, error) {
 	switch p.state {
 	case EntryInvalid:
 		p.metricPos = 0
+		p.exemplarPos = 0
 		p.fieldPos = -2
 		n, err := readDelimited(p.in[p.inPos:], p.mf)
 		p.inPos += n
@@ -485,6 +486,7 @@ func (p *ProtobufParser) Next() (Entry, error) {
 			p.metricPos++
 			p.fieldPos = -2
 			p.fieldsDone = false
+			p.exemplarPos = 0
 			// If this is a metric family containing native
 			// histograms, we have to switch back to native
 			// histograms after parsing a classic histogram.

model/textparse/protobufparse_test.go

@@ -695,6 +695,70 @@ metric: <
   timestamp_ms: 1234568
 >
 
+`,
+
+		`name: "test_histogram_with_native_histogram_exemplars2"
+help: "Another histogram with native histogram exemplars."
+type: HISTOGRAM
+metric: <
+  histogram: <
+    sample_count: 175
+    sample_sum: 0.0008280461746287094
+    bucket: <
+      cumulative_count: 2
+      upper_bound: -0.0004899999999999998
+    >
+    bucket: <
+      cumulative_count: 4
+      upper_bound: -0.0003899999999999998
+    >
+    bucket: <
+      cumulative_count: 16
+      upper_bound: -0.0002899999999999998
+    >
+    schema: 3
+    zero_threshold: 2.938735877055719e-39
+    zero_count: 2
+    negative_span: <
+      offset: -162
+      length: 1
+    >
+    negative_span: <
+      offset: 23
+      length: 4
+    >
+    negative_delta: 1
+    negative_delta: 3
+    negative_delta: -2
+    negative_delta: -1
+    negative_delta: 1
+    positive_span: <
+      offset: -161
+      length: 1
+    >
+    positive_span: <
+      offset: 8
+      length: 3
+    >
+    positive_delta: 1
+    positive_delta: 2
+    positive_delta: -1
+    positive_delta: -1
+    exemplars: <
+      label: <
+        name: "dummyID"
+        value: "59780"
+      >
+      value: -0.00039
+      timestamp: <
+        seconds: 1625851155
+        nanos: 146848499
+      >
+    >
+  >
+  timestamp_ms: 1234568
+>
+
 `,
 	}
 
@@ -1276,6 +1340,41 @@ func TestProtobufParse(t *testing.T) {
 						{Labels: labels.FromStrings("dummyID", "59772"), Value: -0.00052, HasTs: true, Ts: 1625851160156},
 					},
 				},
+				{
+					m:    "test_histogram_with_native_histogram_exemplars2",
+					help: "Another histogram with native histogram exemplars.",
+				},
+				{
+					m:   "test_histogram_with_native_histogram_exemplars2",
+					typ: model.MetricTypeHistogram,
+				},
+				{
+					m: "test_histogram_with_native_histogram_exemplars2",
+					t: 1234568,
+					shs: &histogram.Histogram{
+						Count:         175,
+						ZeroCount:     2,
+						Sum:           0.0008280461746287094,
+						ZeroThreshold: 2.938735877055719e-39,
+						Schema:        3,
+						PositiveSpans: []histogram.Span{
+							{Offset: -161, Length: 1},
+							{Offset: 8, Length: 3},
+						},
+						NegativeSpans: []histogram.Span{
+							{Offset: -162, Length: 1},
+							{Offset: 23, Length: 4},
+						},
+						PositiveBuckets: []int64{1, 2, -1, -1},
+						NegativeBuckets: []int64{1, 3, -2, -1, 1},
+					},
+					lset: labels.FromStrings(
+						"__name__", "test_histogram_with_native_histogram_exemplars2",
+					),
+					e: []exemplar.Exemplar{
+						{Labels: labels.FromStrings("dummyID", "59780"), Value: -0.00039, HasTs: true, Ts: 1625851155146},
+					},
+				},
 			},
 		},
 		{
@@ -1995,15 +2094,15 @@ func TestProtobufParse(t *testing.T) {
 						"__name__", "without_quantiles_sum",
 					),
 				},
-				{ // 78
+				{ // 81
 					m:    "empty_histogram",
 					help: "A histogram without observations and with a zero threshold of zero but with a no-op span to identify it as a native histogram.",
 				},
-				{ // 79
+				{ // 82
 					m:   "empty_histogram",
 					typ: model.MetricTypeHistogram,
 				},
-				{ // 80
+				{ // 83
 					m: "empty_histogram",
 					shs: &histogram.Histogram{
 						CounterResetHint: histogram.UnknownCounterReset,
@@ -2014,15 +2113,15 @@ func TestProtobufParse(t *testing.T) {
 						"__name__", "empty_histogram",
 					),
 				},
-				{ // 81
+				{ // 84
 					m:    "test_counter_with_createdtimestamp",
 					help: "A counter with a created timestamp.",
 				},
-				{ // 82
+				{ // 85
 					m:   "test_counter_with_createdtimestamp",
 					typ: model.MetricTypeCounter,
 				},
-				{ // 83
+				{ // 86
 					m:  "test_counter_with_createdtimestamp",
 					v:  42,
 					ct: 1000,
@@ -2030,15 +2129,15 @@ func TestProtobufParse(t *testing.T) {
 						"__name__", "test_counter_with_createdtimestamp",
 					),
 				},
-				{ // 84
+				{ // 87
 					m:    "test_summary_with_createdtimestamp",
 					help: "A summary with a created timestamp.",
 				},
-				{ // 85
+				{ // 88
 					m:   "test_summary_with_createdtimestamp",
 					typ: model.MetricTypeSummary,
 				},
-				{ // 86
+				{ // 89
 					m:  "test_summary_with_createdtimestamp_count",
 					v:  42,
 					ct: 1000,
@@ -2046,7 +2145,7 @@ func TestProtobufParse(t *testing.T) {
 						"__name__", "test_summary_with_createdtimestamp_count",
 					),
 				},
-				{ // 87
+				{ // 90
 					m:  "test_summary_with_createdtimestamp_sum",
 					v:  1.234,
 					ct: 1000,
@@ -2054,15 +2153,15 @@ func TestProtobufParse(t *testing.T) {
 						"__name__", "test_summary_with_createdtimestamp_sum",
 					),
 				},
-				{ // 88
+				{ // 91
 					m:    "test_histogram_with_createdtimestamp",
 					help: "A histogram with a created timestamp.",
 				},
-				{ // 89
+				{ // 92
 					m:   "test_histogram_with_createdtimestamp",
 					typ: model.MetricTypeHistogram,
 				},
-				{ // 90
+				{ // 93
 					m:  "test_histogram_with_createdtimestamp",
 					ct: 1000,
 					shs: &histogram.Histogram{
@@ -2074,15 +2173,15 @@ func TestProtobufParse(t *testing.T) {
 						"__name__", "test_histogram_with_createdtimestamp",
 					),
 				},
-				{ // 91
+				{ // 94
 					m:    "test_gaugehistogram_with_createdtimestamp",
 					help: "A gauge histogram with a created timestamp.",
 				},
-				{ // 92
+				{ // 95
 					m:   "test_gaugehistogram_with_createdtimestamp",
 					typ: model.MetricTypeGaugeHistogram,
 				},
-				{ // 93
+				{ // 96
 					m:  "test_gaugehistogram_with_createdtimestamp",
 					ct: 1000,
 					shs: &histogram.Histogram{
@@ -2094,15 +2193,15 @@ func TestProtobufParse(t *testing.T) {
 						"__name__", "test_gaugehistogram_with_createdtimestamp",
 					),
 				},
-				{ // 94
+				{ // 97
 					m:    "test_histogram_with_native_histogram_exemplars",
 					help: "A histogram with native histogram exemplars.",
 				},
-				{ // 95
+				{ // 98
 					m:   "test_histogram_with_native_histogram_exemplars",
 					typ: model.MetricTypeHistogram,
 				},
-				{ // 96
+				{ // 99
 					m: "test_histogram_with_native_histogram_exemplars",
 					t: 1234568,
 					shs: &histogram.Histogram{
@@ -2130,7 +2229,7 @@ func TestProtobufParse(t *testing.T) {
 						{Labels: labels.FromStrings("dummyID", "59772"), Value: -0.00052, HasTs: true, Ts: 1625851160156},
 					},
 				},
-				{ // 97
+				{ // 100
 					m: "test_histogram_with_native_histogram_exemplars_count",
 					t: 1234568,
 					v: 175,
@@ -2138,7 +2237,7 @@ func TestProtobufParse(t *testing.T) {
 						"__name__", "test_histogram_with_native_histogram_exemplars_count",
 					),
 				},
-				{ // 98
+				{ // 101
 					m: "test_histogram_with_native_histogram_exemplars_sum",
 					t: 1234568,
 					v: 0.0008280461746287094,
@@ -2146,7 +2245,7 @@ func TestProtobufParse(t *testing.T) {
 						"__name__", "test_histogram_with_native_histogram_exemplars_sum",
 					),
 				},
-				{ // 99
+				{ // 102
 					m: "test_histogram_with_native_histogram_exemplars_bucket\xffle\xff-0.0004899999999999998",
 					t: 1234568,
 					v: 2,
@@ -2155,7 +2254,7 @@ func TestProtobufParse(t *testing.T) {
 						"le", "-0.0004899999999999998",
 					),
 				},
-				{ // 100
+				{ // 103
 					m: "test_histogram_with_native_histogram_exemplars_bucket\xffle\xff-0.0003899999999999998",
 					t: 1234568,
 					v: 4,
@@ -2167,7 +2266,7 @@ func TestProtobufParse(t *testing.T) {
 						{Labels: labels.FromStrings("dummyID", "59727"), Value: -0.00039, HasTs: true, Ts: 1625851155146},
 					},
 				},
-				{ // 101
+				{ // 104
 					m: "test_histogram_with_native_histogram_exemplars_bucket\xffle\xff-0.0002899999999999998",
 					t: 1234568,
 					v: 16,
@@ -2179,7 +2278,7 @@ func TestProtobufParse(t *testing.T) {
 						{Labels: labels.FromStrings("dummyID", "5617"), Value: -0.00029, HasTs: false},
 					},
 				},
-				{ // 102
+				{ // 105
 					m: "test_histogram_with_native_histogram_exemplars_bucket\xffle\xff+Inf",
 					t: 1234568,
 					v: 175,
@@ -2188,6 +2287,93 @@ func TestProtobufParse(t *testing.T) {
 						"le", "+Inf",
 					),
 				},
+				{ // 106
+					m:    "test_histogram_with_native_histogram_exemplars2",
+					help: "Another histogram with native histogram exemplars.",
+				},
+				{ // 107
+					m:   "test_histogram_with_native_histogram_exemplars2",
+					typ: model.MetricTypeHistogram,
+				},
+				{ // 108
+					m: "test_histogram_with_native_histogram_exemplars2",
+					t: 1234568,
+					shs: &histogram.Histogram{
+						Count:         175,
+						ZeroCount:     2,
+						Sum:           0.0008280461746287094,
+						ZeroThreshold: 2.938735877055719e-39,
+						Schema:        3,
+						PositiveSpans: []histogram.Span{
+							{Offset: -161, Length: 1},
+							{Offset: 8, Length: 3},
+						},
+						NegativeSpans: []histogram.Span{
+							{Offset: -162, Length: 1},
+							{Offset: 23, Length: 4},
+						},
+						PositiveBuckets: []int64{1, 2, -1, -1},
+						NegativeBuckets: []int64{1, 3, -2, -1, 1},
+					},
+					lset: labels.FromStrings(
+						"__name__", "test_histogram_with_native_histogram_exemplars2",
+					),
+					e: []exemplar.Exemplar{
+						{Labels: labels.FromStrings("dummyID", "59780"), Value: -0.00039, HasTs: true, Ts: 1625851155146},
+					},
+				},
+				{ // 109
+					m: "test_histogram_with_native_histogram_exemplars2_count",
+					t: 1234568,
+					v: 175,
+					lset: labels.FromStrings(
+						"__name__", "test_histogram_with_native_histogram_exemplars2_count",
+					),
+				},
+				{ // 110
+					m: "test_histogram_with_native_histogram_exemplars2_sum",
+					t: 1234568,
+					v: 0.0008280461746287094,
+					lset: labels.FromStrings(
+						"__name__", "test_histogram_with_native_histogram_exemplars2_sum",
+					),
+				},
+				{ // 111
+					m: "test_histogram_with_native_histogram_exemplars2_bucket\xffle\xff-0.0004899999999999998",
+					t: 1234568,
+					v: 2,
+					lset: labels.FromStrings(
+						"__name__", "test_histogram_with_native_histogram_exemplars2_bucket",
+						"le", "-0.0004899999999999998",
+					),
+				},
+				{ // 112
+					m: "test_histogram_with_native_histogram_exemplars2_bucket\xffle\xff-0.0003899999999999998",
+					t: 1234568,
+					v: 4,
+					lset: labels.FromStrings(
+						"__name__", "test_histogram_with_native_histogram_exemplars2_bucket",
+						"le", "-0.0003899999999999998",
+					),
+				},
+				{ // 113
+					m: "test_histogram_with_native_histogram_exemplars2_bucket\xffle\xff-0.0002899999999999998",
+					t: 1234568,
+					v: 16,
+					lset: labels.FromStrings(
+						"__name__", "test_histogram_with_native_histogram_exemplars2_bucket",
+						"le", "-0.0002899999999999998",
+					),
+				},
+				{ // 114
+					m: "test_histogram_with_native_histogram_exemplars2_bucket\xffle\xff+Inf",
+					t: 1234568,
+					v: 175,
+					lset: labels.FromStrings(
+						"__name__", "test_histogram_with_native_histogram_exemplars2_bucket",
+						"le", "+Inf",
+					),
+				},
 			},
 		},
 	}

notifier/notifier.go

@@ -674,7 +674,6 @@ func (n *Manager) sendOne(ctx context.Context, c *http.Client, url string, b []b
 	}()
 
 	// Any HTTP status 2xx is OK.
-	//nolint:usestdlibvars
 	if resp.StatusCode/100 != 2 {
 		return fmt.Errorf("bad response status %s", resp.Status)
 	}

notifier/notifier_test.go

@@ -711,7 +711,7 @@ func TestHangingNotifier(t *testing.T) {
 	)
 
 	var (
-		sendTimeout = 10 * time.Millisecond
+		sendTimeout = 100 * time.Millisecond
 		sdUpdatert  = sendTimeout / 2
 
 		done = make(chan struct{})

prompb/io/prometheus/write/v2/types.pb.go

@@ -302,15 +302,10 @@ type Exemplar struct {
 	// value represents an exact example value. This can be useful when the exemplar
 	// is attached to a histogram, which only gives an estimated value through buckets.
 	Value float64 `protobuf:"fixed64,2,opt,name=value,proto3" json:"value,omitempty"`
-	// timestamp represents an optional timestamp of the sample in ms.
+	// timestamp represents the timestamp of the exemplar in ms.
 	//
 	// For Go, see github.com/prometheus/prometheus/model/timestamp/timestamp.go
 	// for conversion from/to time.Time to Prometheus timestamp.
-	//
-	// Note that the "optional" keyword is omitted due to
-	// https://cloud.google.com/apis/design/design_patterns.md#optional_primitive_fields
-	// Zero value means value not set. If you need to use exactly zero value for
-	// the timestamp, use 1 millisecond before or after.
 	Timestamp            int64    `protobuf:"varint,3,opt,name=timestamp,proto3" json:"timestamp,omitempty"`
 	XXX_NoUnkeyedLiteral struct{} `json:"-"`
 	XXX_unrecognized     []byte   `json:"-"`

prompb/io/prometheus/write/v2/types.proto

@@ -107,15 +107,10 @@ message Exemplar {
   // value represents an exact example value. This can be useful when the exemplar
   // is attached to a histogram, which only gives an estimated value through buckets.
   double value = 2;
-  // timestamp represents an optional timestamp of the sample in ms.
+  // timestamp represents the timestamp of the exemplar in ms.
   //
   // For Go, see github.com/prometheus/prometheus/model/timestamp/timestamp.go
   // for conversion from/to time.Time to Prometheus timestamp.
-  //
-  // Note that the "optional" keyword is omitted due to
-  // https://cloud.google.com/apis/design/design_patterns.md#optional_primitive_fields
-  // Zero value means value not set. If you need to use exactly zero value for
-  // the timestamp, use 1 millisecond before or after.
   int64 timestamp = 3;
 }
 

promql/bench_test.go

@@ -25,6 +25,7 @@ import (
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/tsdb/tsdbutil"
 	"github.com/prometheus/prometheus/util/teststorage"
@@ -165,6 +166,9 @@ func rangeQueryCases() []benchCase {
 		{
 			expr: "sum(a_X)",
 		},
+		{
+			expr: "avg(a_X)",
+		},
 		{
 			expr: "sum without (l)(h_X)",
 		},
@@ -271,7 +275,7 @@ func BenchmarkRangeQuery(b *testing.B) {
 		MaxSamples: 50000000,
 		Timeout:    100 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(b, opts)
 
 	const interval = 10000 // 10s interval.
 	// A day of data plus 10k steps.
@@ -362,7 +366,7 @@ func BenchmarkNativeHistograms(b *testing.B) {
 
 	for _, tc := range cases {
 		b.Run(tc.name, func(b *testing.B) {
-			ng := promql.NewEngine(opts)
+			ng := promqltest.NewTestEngineWithOpts(b, opts)
 			for i := 0; i < b.N; i++ {
 				qry, err := ng.NewRangeQuery(context.Background(), testStorage, nil, tc.query, start, end, step)
 				if err != nil {

promql/engine.go

@@ -19,6 +19,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"io"
 	"math"
 	"reflect"
 	"runtime"
@@ -271,6 +272,8 @@ func contextErr(err error, env string) error {
 //
 // 2) Enforcement of the maximum number of concurrent queries.
 type QueryTracker interface {
+	io.Closer
+
 	// GetMaxConcurrent returns maximum number of concurrent queries that are allowed by this tracker.
 	GetMaxConcurrent() int
 
@@ -313,6 +316,11 @@ type EngineOpts struct {
 
 	// EnablePerStepStats if true allows for per-step stats to be computed on request. Disabled otherwise.
 	EnablePerStepStats bool
+
+	// EnableDelayedNameRemoval delays the removal of the __name__ label to the last step of the query evaluation.
+	// This is useful in certain scenarios where the __name__ label must be preserved or where applying a
+	// regex-matcher to the __name__ label may otherwise lead to duplicate labelset errors.
+	EnableDelayedNameRemoval bool
 }
 
 // Engine handles the lifetime of queries from beginning to end.
@@ -330,6 +338,7 @@ type Engine struct {
 	enableAtModifier         bool
 	enableNegativeOffset     bool
 	enablePerStepStats       bool
+	enableDelayedNameRemoval bool
 }
 
 // NewEngine returns a new engine.
@@ -420,9 +429,18 @@ func NewEngine(opts EngineOpts) *Engine {
 		enableAtModifier:         opts.EnableAtModifier,
 		enableNegativeOffset:     opts.EnableNegativeOffset,
 		enablePerStepStats:       opts.EnablePerStepStats,
+		enableDelayedNameRemoval: opts.EnableDelayedNameRemoval,
 	}
 }
 
+// Close closes ng.
+func (ng *Engine) Close() error {
+	if ng.activeQueryTracker != nil {
+		return ng.activeQueryTracker.Close()
+	}
+	return nil
+}
+
 // SetQueryLogger sets the query logger.
 func (ng *Engine) SetQueryLogger(l QueryLogger) {
 	ng.queryLoggerLock.Lock()
@@ -573,7 +591,7 @@ func (ng *Engine) validateOpts(expr parser.Expr) error {
 	return validationErr
 }
 
-// NewTestQuery: inject special behaviour into Query for testing.
+// NewTestQuery injects special behaviour into Query for testing.
 func (ng *Engine) NewTestQuery(f func(context.Context) error) Query {
 	qry := &query{
 		q:           "test statement",
@@ -706,16 +724,16 @@ func (ng *Engine) execEvalStmt(ctx context.Context, query *query, s *parser.Eval
 			startTimestamp:           start,
 			endTimestamp:             start,
 			interval:                 1,
-			ctx:                      ctxInnerEval,
 			maxSamples:               ng.maxSamplesPerQuery,
 			logger:                   ng.logger,
 			lookbackDelta:            s.LookbackDelta,
 			samplesStats:             query.sampleStats,
 			noStepSubqueryIntervalFn: ng.noStepSubqueryIntervalFn,
+			enableDelayedNameRemoval: ng.enableDelayedNameRemoval,
 		}
 		query.sampleStats.InitStepTracking(start, start, 1)
 
-		val, warnings, err := evaluator.Eval(s.Expr)
+		val, warnings, err := evaluator.Eval(ctxInnerEval, s.Expr)
 
 		evalSpanTimer.Finish()
 
@@ -743,9 +761,9 @@ func (ng *Engine) execEvalStmt(ctx context.Context, query *query, s *parser.Eval
 				// Point might have a different timestamp, force it to the evaluation
 				// timestamp as that is when we ran the evaluation.
 				if len(s.Histograms) > 0 {
-					vector[i] = Sample{Metric: s.Metric, H: s.Histograms[0].H, T: start}
+					vector[i] = Sample{Metric: s.Metric, H: s.Histograms[0].H, T: start, DropName: s.DropName}
 				} else {
-					vector[i] = Sample{Metric: s.Metric, F: s.Floats[0].F, T: start}
+					vector[i] = Sample{Metric: s.Metric, F: s.Floats[0].F, T: start, DropName: s.DropName}
 				}
 			}
 			return vector, warnings, nil
@@ -764,15 +782,15 @@ func (ng *Engine) execEvalStmt(ctx context.Context, query *query, s *parser.Eval
 		startTimestamp:           timeMilliseconds(s.Start),
 		endTimestamp:             timeMilliseconds(s.End),
 		interval:                 durationMilliseconds(s.Interval),
-		ctx:                      ctxInnerEval,
 		maxSamples:               ng.maxSamplesPerQuery,
 		logger:                   ng.logger,
 		lookbackDelta:            s.LookbackDelta,
 		samplesStats:             query.sampleStats,
 		noStepSubqueryIntervalFn: ng.noStepSubqueryIntervalFn,
+		enableDelayedNameRemoval: ng.enableDelayedNameRemoval,
 	}
 	query.sampleStats.InitStepTracking(evaluator.startTimestamp, evaluator.endTimestamp, evaluator.interval)
-	val, warnings, err := evaluator.Eval(s.Expr)
+	val, warnings, err := evaluator.Eval(ctxInnerEval, s.Expr)
 
 	evalSpanTimer.Finish()
 
@@ -984,6 +1002,8 @@ func checkAndExpandSeriesSet(ctx context.Context, expr parser.Expr) (annotations
 		if e.Series != nil {
 			return nil, nil
 		}
+		span := trace.SpanFromContext(ctx)
+		span.AddEvent("expand start", trace.WithAttributes(attribute.String("selector", e.String())))
 		series, ws, err := expandSeriesSet(ctx, e.UnexpandedSeriesSet)
 		if e.SkipHistogramBuckets {
 			for i := range series {
@@ -991,6 +1011,7 @@ func checkAndExpandSeriesSet(ctx context.Context, expr parser.Expr) (annotations
 			}
 		}
 		e.Series = series
+		span.AddEvent("expand end", trace.WithAttributes(attribute.Int("num_series", len(series))))
 		return ws, err
 	}
 	return nil, nil
@@ -1020,8 +1041,6 @@ func (e errWithWarnings) Error() string { return e.err.Error() }
 // querier and reports errors. On timeout or cancellation of its context it
 // terminates.
 type evaluator struct {
-	ctx context.Context
-
 	startTimestamp int64 // Start time in milliseconds.
 	endTimestamp   int64 // End time in milliseconds.
 	interval       int64 // Interval in milliseconds.
@@ -1032,6 +1051,7 @@ type evaluator struct {
 	lookbackDelta            time.Duration
 	samplesStats             *stats.QuerySamples
 	noStepSubqueryIntervalFn func(rangeMillis int64) int64
+	enableDelayedNameRemoval bool
 }
 
 // errorf causes a panic with the input formatted into an error.
@@ -1057,7 +1077,7 @@ func (ev *evaluator) recover(expr parser.Expr, ws *annotations.Annotations, errp
 		buf := make([]byte, 64<<10)
 		buf = buf[:runtime.Stack(buf, false)]
 
-		level.Error(ev.logger).Log("msg", "runtime panic in parser", "expr", expr.String(), "err", e, "stacktrace", string(buf))
+		level.Error(ev.logger).Log("msg", "runtime panic during query evaluation", "expr", expr.String(), "err", e, "stacktrace", string(buf))
 		*errp = fmt.Errorf("unexpected error: %w", err)
 	case errWithWarnings:
 		*errp = err.err
@@ -1069,10 +1089,13 @@ func (ev *evaluator) recover(expr parser.Expr, ws *annotations.Annotations, errp
 	}
 }
 
-func (ev *evaluator) Eval(expr parser.Expr) (v parser.Value, ws annotations.Annotations, err error) {
+func (ev *evaluator) Eval(ctx context.Context, expr parser.Expr) (v parser.Value, ws annotations.Annotations, err error) {
 	defer ev.recover(expr, &ws, &err)
 
-	v, ws = ev.eval(expr)
+	v, ws = ev.eval(ctx, expr)
+	if ev.enableDelayedNameRemoval {
+		ev.cleanupMetricLabels(v)
+	}
 	return v, ws, nil
 }
 
@@ -1101,6 +1124,9 @@ type EvalNodeHelper struct {
 	rightSigs    map[string]Sample
 	matchedSigs  map[string]map[uint64]struct{}
 	resultMetric map[string]labels.Labels
+
+	// Additional options for the evaluation.
+	enableDelayedNameRemoval bool
 }
 
 func (enh *EvalNodeHelper) resetBuilder(lbls labels.Labels) {
@@ -1117,7 +1143,7 @@ func (enh *EvalNodeHelper) resetBuilder(lbls labels.Labels) {
 // function call results.
 // The prepSeries function (if provided) can be used to prepare the helper
 // for each series, then passed to each call funcCall.
-func (ev *evaluator) rangeEval(prepSeries func(labels.Labels, *EvalSeriesHelper), funcCall func([]parser.Value, [][]EvalSeriesHelper, *EvalNodeHelper) (Vector, annotations.Annotations), exprs ...parser.Expr) (Matrix, annotations.Annotations) {
+func (ev *evaluator) rangeEval(ctx context.Context, prepSeries func(labels.Labels, *EvalSeriesHelper), funcCall func([]parser.Value, [][]EvalSeriesHelper, *EvalNodeHelper) (Vector, annotations.Annotations), exprs ...parser.Expr) (Matrix, annotations.Annotations) {
 	numSteps := int((ev.endTimestamp-ev.startTimestamp)/ev.interval) + 1
 	matrixes := make([]Matrix, len(exprs))
 	origMatrixes := make([]Matrix, len(exprs))
@@ -1128,7 +1154,7 @@ func (ev *evaluator) rangeEval(prepSeries func(labels.Labels, *EvalSeriesHelper)
 		// Functions will take string arguments from the expressions, not the values.
 		if e != nil && e.Type() != parser.ValueTypeString {
 			// ev.currentSamples will be updated to the correct value within the ev.eval call.
-			val, ws := ev.eval(e)
+			val, ws := ev.eval(ctx, e)
 			warnings.Merge(ws)
 			matrixes[i] = val.(Matrix)
 
@@ -1150,7 +1176,7 @@ func (ev *evaluator) rangeEval(prepSeries func(labels.Labels, *EvalSeriesHelper)
 			biggestLen = len(matrixes[i])
 		}
 	}
-	enh := &EvalNodeHelper{Out: make(Vector, 0, biggestLen)}
+	enh := &EvalNodeHelper{Out: make(Vector, 0, biggestLen), enableDelayedNameRemoval: ev.enableDelayedNameRemoval}
 	type seriesAndTimestamp struct {
 		Series
 		ts int64
@@ -1180,7 +1206,7 @@ func (ev *evaluator) rangeEval(prepSeries func(labels.Labels, *EvalSeriesHelper)
 	}
 
 	for ts := ev.startTimestamp; ts <= ev.endTimestamp; ts += ev.interval {
-		if err := contextDone(ev.ctx, "expression evaluation"); err != nil {
+		if err := contextDone(ctx, "expression evaluation"); err != nil {
 			ev.error(err)
 		}
 		// Reset number of samples in memory after each timestamp.
@@ -1196,12 +1222,12 @@ func (ev *evaluator) rangeEval(prepSeries func(labels.Labels, *EvalSeriesHelper)
 			for si, series := range matrixes[i] {
 				switch {
 				case len(series.Floats) > 0 && series.Floats[0].T == ts:
-					vectors[i] = append(vectors[i], Sample{Metric: series.Metric, F: series.Floats[0].F, T: ts})
+					vectors[i] = append(vectors[i], Sample{Metric: series.Metric, F: series.Floats[0].F, T: ts, DropName: series.DropName})
 					// Move input vectors forward so we don't have to re-scan the same
 					// past points at the next step.
 					matrixes[i][si].Floats = series.Floats[1:]
 				case len(series.Histograms) > 0 && series.Histograms[0].T == ts:
-					vectors[i] = append(vectors[i], Sample{Metric: series.Metric, H: series.Histograms[0].H, T: ts})
+					vectors[i] = append(vectors[i], Sample{Metric: series.Metric, H: series.Histograms[0].H, T: ts, DropName: series.DropName})
 					matrixes[i][si].Histograms = series.Histograms[1:]
 				default:
 					continue
@@ -1240,15 +1266,15 @@ func (ev *evaluator) rangeEval(prepSeries func(labels.Labels, *EvalSeriesHelper)
 
 		// If this could be an instant query, shortcut so as not to change sort order.
 		if ev.endTimestamp == ev.startTimestamp {
-			if result.ContainsSameLabelset() {
+			if !ev.enableDelayedNameRemoval && result.ContainsSameLabelset() {
 				ev.errorf("vector cannot contain metrics with the same labelset")
 			}
 			mat := make(Matrix, len(result))
 			for i, s := range result {
 				if s.H == nil {
-					mat[i] = Series{Metric: s.Metric, Floats: []FPoint{{T: ts, F: s.F}}}
+					mat[i] = Series{Metric: s.Metric, Floats: []FPoint{{T: ts, F: s.F}}, DropName: s.DropName}
 				} else {
-					mat[i] = Series{Metric: s.Metric, Histograms: []HPoint{{T: ts, H: s.H}}}
+					mat[i] = Series{Metric: s.Metric, Histograms: []HPoint{{T: ts, H: s.H}}, DropName: s.DropName}
 				}
 			}
 			ev.currentSamples = originalNumSamples + mat.TotalSamples()
@@ -1266,7 +1292,7 @@ func (ev *evaluator) rangeEval(prepSeries func(labels.Labels, *EvalSeriesHelper)
 				}
 				ss.ts = ts
 			} else {
-				ss = seriesAndTimestamp{Series{Metric: sample.Metric}, ts}
+				ss = seriesAndTimestamp{Series{Metric: sample.Metric, DropName: sample.DropName}, ts}
 			}
 			addToSeries(&ss.Series, enh.Ts, sample.F, sample.H, numSteps)
 			seriess[h] = ss
@@ -1290,7 +1316,7 @@ func (ev *evaluator) rangeEval(prepSeries func(labels.Labels, *EvalSeriesHelper)
 	return mat, warnings
 }
 
-func (ev *evaluator) rangeEvalAgg(aggExpr *parser.AggregateExpr, sortedGrouping []string, inputMatrix Matrix, param float64) (Matrix, annotations.Annotations) {
+func (ev *evaluator) rangeEvalAgg(ctx context.Context, aggExpr *parser.AggregateExpr, sortedGrouping []string, inputMatrix Matrix, param float64) (Matrix, annotations.Annotations) {
 	// Keep a copy of the original point slice so that it can be returned to the pool.
 	origMatrix := slices.Clone(inputMatrix)
 	defer func() {
@@ -1302,7 +1328,7 @@ func (ev *evaluator) rangeEvalAgg(aggExpr *parser.AggregateExpr, sortedGrouping
 
 	var warnings annotations.Annotations
 
-	enh := &EvalNodeHelper{}
+	enh := &EvalNodeHelper{enableDelayedNameRemoval: ev.enableDelayedNameRemoval}
 	tempNumSamples := ev.currentSamples
 
 	// Create a mapping from input series to output groups.
@@ -1370,7 +1396,7 @@ func (ev *evaluator) rangeEvalAgg(aggExpr *parser.AggregateExpr, sortedGrouping
 	}
 
 	for ts := ev.startTimestamp; ts <= ev.endTimestamp; ts += ev.interval {
-		if err := contextDone(ev.ctx, "expression evaluation"); err != nil {
+		if err := contextDone(ctx, "expression evaluation"); err != nil {
 			ev.error(err)
 		}
 		// Reset number of samples in memory after each timestamp.
@@ -1421,11 +1447,11 @@ func (ev *evaluator) rangeEvalAgg(aggExpr *parser.AggregateExpr, sortedGrouping
 
 // evalSubquery evaluates given SubqueryExpr and returns an equivalent
 // evaluated MatrixSelector in its place. Note that the Name and LabelMatchers are not set.
-func (ev *evaluator) evalSubquery(subq *parser.SubqueryExpr) (*parser.MatrixSelector, int, annotations.Annotations) {
+func (ev *evaluator) evalSubquery(ctx context.Context, subq *parser.SubqueryExpr) (*parser.MatrixSelector, int, annotations.Annotations) {
 	samplesStats := ev.samplesStats
 	// Avoid double counting samples when running a subquery, those samples will be counted in later stage.
 	ev.samplesStats = ev.samplesStats.NewChild()
-	val, ws := ev.eval(subq)
+	val, ws := ev.eval(ctx, subq)
 	// But do incorporate the peak from the subquery
 	samplesStats.UpdatePeakFromSubquery(ev.samplesStats)
 	ev.samplesStats = samplesStats
@@ -1452,18 +1478,20 @@ func (ev *evaluator) evalSubquery(subq *parser.SubqueryExpr) (*parser.MatrixSele
 }
 
 // eval evaluates the given expression as the given AST expression node requires.
-func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotations) {
+func (ev *evaluator) eval(ctx context.Context, expr parser.Expr) (parser.Value, annotations.Annotations) {
 	// This is the top-level evaluation method.
 	// Thus, we check for timeout/cancellation here.
-	if err := contextDone(ev.ctx, "expression evaluation"); err != nil {
+	if err := contextDone(ctx, "expression evaluation"); err != nil {
 		ev.error(err)
 	}
 	numSteps := int((ev.endTimestamp-ev.startTimestamp)/ev.interval) + 1
 
 	// Create a new span to help investigate inner evaluation performances.
-	ctxWithSpan, span := otel.Tracer("").Start(ev.ctx, stats.InnerEvalTime.SpanOperation()+" eval "+reflect.TypeOf(expr).String())
+	ctx, span := otel.Tracer("").Start(ctx, stats.InnerEvalTime.SpanOperation()+" eval "+reflect.TypeOf(expr).String())
-	ev.ctx = ctxWithSpan
 	defer span.End()
+	if ss, ok := expr.(interface{ ShortString() string }); ok {
+		span.SetAttributes(attribute.String("operation", ss.ShortString()))
+	}
 
 	switch e := expr.(type) {
 	case *parser.AggregateExpr:
@@ -1484,7 +1512,7 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 				sortedGrouping = append(sortedGrouping, valueLabel.Val)
 				slices.Sort(sortedGrouping)
 			}
-			return ev.rangeEval(nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+			return ev.rangeEval(ctx, nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 				return ev.aggregationCountValues(e, sortedGrouping, valueLabel.Val, v[0].(Vector), enh)
 			}, e.Expr)
 		}
@@ -1494,16 +1522,16 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 		// param is the number k for topk/bottomk, or q for quantile.
 		var fParam float64
 		if param != nil {
-			val, ws := ev.eval(param)
+			val, ws := ev.eval(ctx, param)
 			warnings.Merge(ws)
 			fParam = val.(Matrix)[0].Floats[0].F
 		}
 		// Now fetch the data to be aggregated.
-		val, ws := ev.eval(e.Expr)
+		val, ws := ev.eval(ctx, e.Expr)
 		warnings.Merge(ws)
 		inputMatrix := val.(Matrix)
 
-		result, ws := ev.rangeEvalAgg(e, sortedGrouping, inputMatrix, fParam)
+		result, ws := ev.rangeEvalAgg(ctx, e, sortedGrouping, inputMatrix, fParam)
 		warnings.Merge(ws)
 		ev.currentSamples = originalNumSamples + result.TotalSamples()
 		ev.samplesStats.UpdatePeak(ev.currentSamples)
@@ -1521,7 +1549,7 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 			unwrapParenExpr(&arg)
 			vs, ok := arg.(*parser.VectorSelector)
 			if ok {
-				return ev.rangeEvalTimestampFunctionOverVectorSelector(vs, call, e)
+				return ev.rangeEvalTimestampFunctionOverVectorSelector(ctx, vs, call, e)
 			}
 		}
 
@@ -1545,7 +1573,7 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 				matrixArgIndex = i
 				matrixArg = true
 				// Replacing parser.SubqueryExpr with parser.MatrixSelector.
-				val, totalSamples, ws := ev.evalSubquery(subq)
+				val, totalSamples, ws := ev.evalSubquery(ctx, subq)
 				e.Args[i] = val
 				warnings.Merge(ws)
 				defer func() {
@@ -1560,14 +1588,14 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 		// Special handling for functions that work on series not samples.
 		switch e.Func.Name {
 		case "label_replace":
-			return ev.evalLabelReplace(e.Args)
+			return ev.evalLabelReplace(ctx, e.Args)
 		case "label_join":
-			return ev.evalLabelJoin(e.Args)
+			return ev.evalLabelJoin(ctx, e.Args)
 		}
 
 		if !matrixArg {
 			// Does not have a matrix argument.
-			return ev.rangeEval(nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+			return ev.rangeEval(ctx, nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 				vec, annos := call(v, e.Args, enh)
 				return vec, warnings.Merge(annos)
 			}, e.Args...)
@@ -1579,7 +1607,7 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 		otherInArgs := make([]Vector, len(e.Args))
 		for i, e := range e.Args {
 			if i != matrixArgIndex {
-				val, ws := ev.eval(e)
+				val, ws := ev.eval(ctx, e)
 				otherArgs[i] = val.(Matrix)
 				otherInArgs[i] = Vector{Sample{}}
 				inArgs[i] = otherInArgs[i]
@@ -1593,7 +1621,7 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 		sel := arg.(*parser.MatrixSelector)
 		selVS := sel.VectorSelector.(*parser.VectorSelector)
 
-		ws, err := checkAndExpandSeriesSet(ev.ctx, sel)
+		ws, err := checkAndExpandSeriesSet(ctx, sel)
 		warnings.Merge(ws)
 		if err != nil {
 			ev.error(errWithWarnings{fmt.Errorf("expanding series: %w", err), warnings})
@@ -1611,12 +1639,19 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 		var prevSS *Series
 		inMatrix := make(Matrix, 1)
 		inArgs[matrixArgIndex] = inMatrix
-		enh := &EvalNodeHelper{Out: make(Vector, 0, 1)}
+		enh := &EvalNodeHelper{Out: make(Vector, 0, 1), enableDelayedNameRemoval: ev.enableDelayedNameRemoval}
 		// Process all the calls for one time series at a time.
 		it := storage.NewBuffer(selRange)
 		var chkIter chunkenc.Iterator
+
+		// The last_over_time function acts like offset; thus, it
+		// should keep the metric name.  For all the other range
+		// vector functions, the only change needed is to drop the
+		// metric name in the output.
+		dropName := e.Func.Name != "last_over_time"
+
 		for i, s := range selVS.Series {
-			if err := contextDone(ev.ctx, "expression evaluation"); err != nil {
+			if err := contextDone(ctx, "expression evaluation"); err != nil {
 				ev.error(err)
 			}
 			ev.currentSamples -= len(floats) + totalHPointSize(histograms)
@@ -1629,15 +1664,12 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 			chkIter = s.Iterator(chkIter)
 			it.Reset(chkIter)
 			metric := selVS.Series[i].Labels()
-			// The last_over_time function acts like offset; thus, it
+			if !ev.enableDelayedNameRemoval && dropName {
-			// should keep the metric name.  For all the other range
-			// vector functions, the only change needed is to drop the
-			// metric name in the output.
-			if e.Func.Name != "last_over_time" {
 				metric = metric.DropMetricName()
 			}
 			ss := Series{
 				Metric:   metric,
+				DropName: dropName,
 			}
 			inMatrix[0].Metric = selVS.Series[i].Labels()
 			for ts, step := ev.startTimestamp, -1; ts <= ev.endTimestamp; ts += ev.interval {
@@ -1754,30 +1786,33 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 				Series{
 					Metric:   createLabelsForAbsentFunction(e.Args[0]),
 					Floats:   newp,
+					DropName: dropName,
 				},
 			}, warnings
 		}
 
-		if mat.ContainsSameLabelset() {
+		if !ev.enableDelayedNameRemoval && mat.ContainsSameLabelset() {
 			ev.errorf("vector cannot contain metrics with the same labelset")
 		}
-
 		return mat, warnings
 
 	case *parser.ParenExpr:
-		return ev.eval(e.Expr)
+		return ev.eval(ctx, e.Expr)
 
 	case *parser.UnaryExpr:
-		val, ws := ev.eval(e.Expr)
+		val, ws := ev.eval(ctx, e.Expr)
 		mat := val.(Matrix)
 		if e.Op == parser.SUB {
 			for i := range mat {
+				if !ev.enableDelayedNameRemoval {
 					mat[i].Metric = mat[i].Metric.DropMetricName()
+				}
+				mat[i].DropName = true
 				for j := range mat[i].Floats {
 					mat[i].Floats[j].F = -mat[i].Floats[j].F
 				}
 			}
-			if mat.ContainsSameLabelset() {
+			if !ev.enableDelayedNameRemoval && mat.ContainsSameLabelset() {
 				ev.errorf("vector cannot contain metrics with the same labelset")
 			}
 		}
@@ -1786,7 +1821,7 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 	case *parser.BinaryExpr:
 		switch lt, rt := e.LHS.Type(), e.RHS.Type(); {
 		case lt == parser.ValueTypeScalar && rt == parser.ValueTypeScalar:
-			return ev.rangeEval(nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+			return ev.rangeEval(ctx, nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 				val := scalarBinop(e.Op, v[0].(Vector)[0].F, v[1].(Vector)[0].F)
 				return append(enh.Out, Sample{F: val}), nil
 			}, e.LHS, e.RHS)
@@ -1799,47 +1834,49 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 			}
 			switch e.Op {
 			case parser.LAND:
-				return ev.rangeEval(initSignatures, func(v []parser.Value, sh [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+				return ev.rangeEval(ctx, initSignatures, func(v []parser.Value, sh [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 					return ev.VectorAnd(v[0].(Vector), v[1].(Vector), e.VectorMatching, sh[0], sh[1], enh), nil
 				}, e.LHS, e.RHS)
 			case parser.LOR:
-				return ev.rangeEval(initSignatures, func(v []parser.Value, sh [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+				return ev.rangeEval(ctx, initSignatures, func(v []parser.Value, sh [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 					return ev.VectorOr(v[0].(Vector), v[1].(Vector), e.VectorMatching, sh[0], sh[1], enh), nil
 				}, e.LHS, e.RHS)
 			case parser.LUNLESS:
-				return ev.rangeEval(initSignatures, func(v []parser.Value, sh [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+				return ev.rangeEval(ctx, initSignatures, func(v []parser.Value, sh [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 					return ev.VectorUnless(v[0].(Vector), v[1].(Vector), e.VectorMatching, sh[0], sh[1], enh), nil
 				}, e.LHS, e.RHS)
 			default:
-				return ev.rangeEval(initSignatures, func(v []parser.Value, sh [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+				return ev.rangeEval(ctx, initSignatures, func(v []parser.Value, sh [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 					vec, err := ev.VectorBinop(e.Op, v[0].(Vector), v[1].(Vector), e.VectorMatching, e.ReturnBool, sh[0], sh[1], enh)
 					return vec, handleVectorBinopError(err, e)
 				}, e.LHS, e.RHS)
 			}
 
 		case lt == parser.ValueTypeVector && rt == parser.ValueTypeScalar:
-			return ev.rangeEval(nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+			return ev.rangeEval(ctx, nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 				vec, err := ev.VectorscalarBinop(e.Op, v[0].(Vector), Scalar{V: v[1].(Vector)[0].F}, false, e.ReturnBool, enh)
 				return vec, handleVectorBinopError(err, e)
 			}, e.LHS, e.RHS)
 
 		case lt == parser.ValueTypeScalar && rt == parser.ValueTypeVector:
-			return ev.rangeEval(nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+			return ev.rangeEval(ctx, nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 				vec, err := ev.VectorscalarBinop(e.Op, v[1].(Vector), Scalar{V: v[0].(Vector)[0].F}, true, e.ReturnBool, enh)
 				return vec, handleVectorBinopError(err, e)
 			}, e.LHS, e.RHS)
 		}
 
 	case *parser.NumberLiteral:
-		return ev.rangeEval(nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+		span.SetAttributes(attribute.Float64("value", e.Val))
+		return ev.rangeEval(ctx, nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 			return append(enh.Out, Sample{F: e.Val, Metric: labels.EmptyLabels()}), nil
 		})
 
 	case *parser.StringLiteral:
+		span.SetAttributes(attribute.String("value", e.Val))
 		return String{V: e.Val, T: ev.startTimestamp}, nil
 
 	case *parser.VectorSelector:
-		ws, err := checkAndExpandSeriesSet(ev.ctx, e)
+		ws, err := checkAndExpandSeriesSet(ctx, e)
 		if err != nil {
 			ev.error(errWithWarnings{fmt.Errorf("expanding series: %w", err), ws})
 		}
@@ -1848,7 +1885,7 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 		it := storage.NewMemoizedEmptyIterator(durationMilliseconds(ev.lookbackDelta))
 		var chkIter chunkenc.Iterator
 		for i, s := range e.Series {
-			if err := contextDone(ev.ctx, "expression evaluation"); err != nil {
+			if err := contextDone(ctx, "expression evaluation"); err != nil {
 				ev.error(err)
 			}
 			chkIter = s.Iterator(chkIter)
@@ -1899,20 +1936,20 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 		if ev.startTimestamp != ev.endTimestamp {
 			panic(errors.New("cannot do range evaluation of matrix selector"))
 		}
-		return ev.matrixSelector(e)
+		return ev.matrixSelector(ctx, e)
 
 	case *parser.SubqueryExpr:
 		offsetMillis := durationMilliseconds(e.Offset)
 		rangeMillis := durationMilliseconds(e.Range)
 		newEv := &evaluator{
 			endTimestamp:             ev.endTimestamp - offsetMillis,
-			ctx:                      ev.ctx,
 			currentSamples:           ev.currentSamples,
 			maxSamples:               ev.maxSamples,
 			logger:                   ev.logger,
 			lookbackDelta:            ev.lookbackDelta,
 			samplesStats:             ev.samplesStats.NewChild(),
 			noStepSubqueryIntervalFn: ev.noStepSubqueryIntervalFn,
+			enableDelayedNameRemoval: ev.enableDelayedNameRemoval,
 		}
 
 		if e.Step != 0 {
@@ -1935,7 +1972,7 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 			setOffsetForAtModifier(newEv.startTimestamp, e.Expr)
 		}
 
-		res, ws := newEv.eval(e.Expr)
+		res, ws := newEv.eval(ctx, e.Expr)
 		ev.currentSamples = newEv.currentSamples
 		ev.samplesStats.UpdatePeakFromSubquery(newEv.samplesStats)
 		ev.samplesStats.IncrementSamplesAtTimestamp(ev.endTimestamp, newEv.samplesStats.TotalSamples)
@@ -1943,22 +1980,22 @@ func (ev *evaluator) eval(expr parser.Expr) (parser.Value, annotations.Annotatio
 	case *parser.StepInvariantExpr:
 		switch ce := e.Expr.(type) {
 		case *parser.StringLiteral, *parser.NumberLiteral:
-			return ev.eval(ce)
+			return ev.eval(ctx, ce)
 		}
 
 		newEv := &evaluator{
 			startTimestamp:           ev.startTimestamp,
 			endTimestamp:             ev.startTimestamp, // Always a single evaluation.
 			interval:                 ev.interval,
-			ctx:                      ev.ctx,
 			currentSamples:           ev.currentSamples,
 			maxSamples:               ev.maxSamples,
 			logger:                   ev.logger,
 			lookbackDelta:            ev.lookbackDelta,
 			samplesStats:             ev.samplesStats.NewChild(),
 			noStepSubqueryIntervalFn: ev.noStepSubqueryIntervalFn,
+			enableDelayedNameRemoval: ev.enableDelayedNameRemoval,
 		}
-		res, ws := newEv.eval(e.Expr)
+		res, ws := newEv.eval(ctx, e.Expr)
 		ev.currentSamples = newEv.currentSamples
 		ev.samplesStats.UpdatePeakFromSubquery(newEv.samplesStats)
 		for ts, step := ev.startTimestamp, -1; ts <= ev.endTimestamp; ts += ev.interval {
@@ -2034,8 +2071,8 @@ func reuseOrGetFPointSlices(prevSS *Series, numSteps int) (r []FPoint) {
 	return getFPointSlice(numSteps)
 }
 
-func (ev *evaluator) rangeEvalTimestampFunctionOverVectorSelector(vs *parser.VectorSelector, call FunctionCall, e *parser.Call) (parser.Value, annotations.Annotations) {
+func (ev *evaluator) rangeEvalTimestampFunctionOverVectorSelector(ctx context.Context, vs *parser.VectorSelector, call FunctionCall, e *parser.Call) (parser.Value, annotations.Annotations) {
-	ws, err := checkAndExpandSeriesSet(ev.ctx, vs)
+	ws, err := checkAndExpandSeriesSet(ctx, vs)
 	if err != nil {
 		ev.error(errWithWarnings{fmt.Errorf("expanding series: %w", err), ws})
 	}
@@ -2046,7 +2083,7 @@ func (ev *evaluator) rangeEvalTimestampFunctionOverVectorSelector(vs *parser.Vec
 		seriesIterators[i] = storage.NewMemoizedIterator(it, durationMilliseconds(ev.lookbackDelta))
 	}
 
-	return ev.rangeEval(nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
+	return ev.rangeEval(ctx, nil, func(v []parser.Value, _ [][]EvalSeriesHelper, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 		if vs.Timestamp != nil {
 			// This is a special case for "timestamp()" when the @ modifier is used, to ensure that
 			// we return a point for each time step in this case.
@@ -2182,7 +2219,7 @@ func putMatrixSelectorHPointSlice(p []HPoint) {
 }
 
 // matrixSelector evaluates a *parser.MatrixSelector expression.
-func (ev *evaluator) matrixSelector(node *parser.MatrixSelector) (Matrix, annotations.Annotations) {
+func (ev *evaluator) matrixSelector(ctx context.Context, node *parser.MatrixSelector) (Matrix, annotations.Annotations) {
 	var (
 		vs = node.VectorSelector.(*parser.VectorSelector)
 
@@ -2193,7 +2230,7 @@ func (ev *evaluator) matrixSelector(node *parser.MatrixSelector) (Matrix, annota
 
 		it = storage.NewBuffer(durationMilliseconds(node.Range))
 	)
-	ws, err := checkAndExpandSeriesSet(ev.ctx, node)
+	ws, err := checkAndExpandSeriesSet(ctx, node)
 	if err != nil {
 		ev.error(errWithWarnings{fmt.Errorf("expanding series: %w", err), ws})
 	}
@@ -2201,7 +2238,7 @@ func (ev *evaluator) matrixSelector(node *parser.MatrixSelector) (Matrix, annota
 	var chkIter chunkenc.Iterator
 	series := vs.Series
 	for i, s := range series {
-		if err := contextDone(ev.ctx, "expression evaluation"); err != nil {
+		if err := contextDone(ctx, "expression evaluation"); err != nil {
 			ev.error(err)
 		}
 		chkIter = s.Iterator(chkIter)
@@ -2356,6 +2393,11 @@ loop:
 		} else {
 			histograms = append(histograms, HPoint{H: &histogram.FloatHistogram{}})
 		}
+		if histograms[n].H == nil {
+			// Make sure to pass non-nil H to AtFloatHistogram so that it does a deep-copy.
+			// Not an issue in the loop above since that uses an intermediate buffer.
+			histograms[n].H = &histogram.FloatHistogram{}
+		}
 		histograms[n].T, histograms[n].H = it.AtFloatHistogram(histograms[n].H)
 		if value.IsStaleNaN(histograms[n].H.Sum) {
 			histograms = histograms[:n]
@@ -2548,7 +2590,7 @@ func (ev *evaluator) VectorBinop(op parser.ItemType, lhs, rhs Vector, matching *
 			continue
 		}
 		metric := resultMetric(ls.Metric, rs.Metric, op, matching, enh)
-		if returnBool {
+		if !ev.enableDelayedNameRemoval && returnBool {
 			metric = metric.DropMetricName()
 		}
 		insertedSigs, exists := matchedSigs[sig]
@@ -2576,6 +2618,7 @@ func (ev *evaluator) VectorBinop(op parser.ItemType, lhs, rhs Vector, matching *
 			Metric:   metric,
 			F:        floatValue,
 			H:        histogramValue,
+			DropName: returnBool,
 		})
 	}
 	return enh.Out, lastErr
@@ -2675,8 +2718,11 @@ func (ev *evaluator) VectorscalarBinop(op parser.ItemType, lhs Vector, rhs Scala
 			lhsSample.F = float
 			lhsSample.H = histogram
 			if shouldDropMetricName(op) || returnBool {
+				if !ev.enableDelayedNameRemoval {
 					lhsSample.Metric = lhsSample.Metric.DropMetricName()
 				}
+				lhsSample.DropName = true
+			}
 			enh.Out = append(enh.Out, lhsSample)
 		}
 	}
@@ -2773,15 +2819,20 @@ func vectorElemBinop(op parser.ItemType, lhs, rhs float64, hlhs, hrhs *histogram
 }
 
 type groupedAggregation struct {
+	floatValue     float64
+	histogramValue *histogram.FloatHistogram
+	floatMean      float64
+	floatKahanC    float64 // "Compensating value" for Kahan summation.
+	groupCount     float64
+	heap           vectorByValueHeap
+
+	// All bools together for better packing within the struct.
 	seen                   bool // Was this output groups seen in the input at this timestamp.
 	hasFloat               bool // Has at least 1 float64 sample aggregated.
 	hasHistogram           bool // Has at least 1 histogram sample aggregated.
-	floatValue        float64
+	incompatibleHistograms bool // If true, group has seen mixed exponential and custom buckets, or incompatible custom buckets.
-	histogramValue    *histogram.FloatHistogram
+	groupAggrComplete      bool // Used by LIMITK to short-cut series loop when we've reached K elem on every group.
-	floatMean         float64 // Mean, or "compensating value" for Kahan summation.
+	incrementalMean        bool // True after reverting to incremental calculation of the mean value.
-	groupCount        int
-	groupAggrComplete bool // Used by LIMITK to short-cut series loop when we've reached K elem on every group
-	heap              vectorByValueHeap
 }
 
 // aggregation evaluates sum, avg, count, stdvar, stddev or quantile at one timestep on inputMatrix.
@@ -2807,13 +2858,12 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 			*group = groupedAggregation{
 				seen:                   true,
 				floatValue:             f,
+				floatMean:              f,
+				incompatibleHistograms: false,
 				groupCount:             1,
 			}
 			switch op {
-			case parser.AVG:
+			case parser.AVG, parser.SUM:
-				group.floatMean = f
-				fallthrough
-			case parser.SUM:
 				if h == nil {
 					group.hasFloat = true
 				} else {
@@ -2821,7 +2871,6 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 					group.hasHistogram = true
 				}
 			case parser.STDVAR, parser.STDDEV:
-				group.floatMean = f
 				group.floatValue = 0
 			case parser.QUANTILE:
 				group.heap = make(vectorByValueHeap, 1)
@@ -2832,6 +2881,10 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 			continue
 		}
 
+		if group.incompatibleHistograms {
+			continue
+		}
+
 		switch op {
 		case parser.SUM:
 			if h != nil {
@@ -2840,6 +2893,7 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 					_, err := group.histogramValue.Add(h)
 					if err != nil {
 						handleAggregationError(err, e, inputMatrix[si].Metric.Get(model.MetricNameLabel), &annos)
+						group.incompatibleHistograms = true
 					}
 				}
 				// Otherwise the aggregation contained floats
@@ -2847,7 +2901,7 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 				// point in copying the histogram in that case.
 			} else {
 				group.hasFloat = true
-				group.floatValue, group.floatMean = kahanSumInc(f, group.floatValue, group.floatMean)
+				group.floatValue, group.floatKahanC = kahanSumInc(f, group.floatValue, group.floatKahanC)
 			}
 
 		case parser.AVG:
@@ -2855,15 +2909,19 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 			if h != nil {
 				group.hasHistogram = true
 				if group.histogramValue != nil {
-					left := h.Copy().Div(float64(group.groupCount))
+					left := h.Copy().Div(group.groupCount)
-					right := group.histogramValue.Copy().Div(float64(group.groupCount))
+					right := group.histogramValue.Copy().Div(group.groupCount)
 					toAdd, err := left.Sub(right)
 					if err != nil {
 						handleAggregationError(err, e, inputMatrix[si].Metric.Get(model.MetricNameLabel), &annos)
+						group.incompatibleHistograms = true
+						continue
 					}
 					_, err = group.histogramValue.Add(toAdd)
 					if err != nil {
 						handleAggregationError(err, e, inputMatrix[si].Metric.Get(model.MetricNameLabel), &annos)
+						group.incompatibleHistograms = true
+						continue
 					}
 				}
 				// Otherwise the aggregation contained floats
@@ -2871,6 +2929,22 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 				// point in copying the histogram in that case.
 			} else {
 				group.hasFloat = true
+				if !group.incrementalMean {
+					newV, newC := kahanSumInc(f, group.floatValue, group.floatKahanC)
+					if !math.IsInf(newV, 0) {
+						// The sum doesn't overflow, so we propagate it to the
+						// group struct and continue with the regular
+						// calculation of the mean value.
+						group.floatValue, group.floatKahanC = newV, newC
+						break
+					}
+					// If we are here, we know that the sum _would_ overflow. So
+					// instead of continue to sum up, we revert to incremental
+					// calculation of the mean value from here on.
+					group.incrementalMean = true
+					group.floatMean = group.floatValue / (group.groupCount - 1)
+					group.floatKahanC /= group.groupCount - 1
+				}
 				if math.IsInf(group.floatMean, 0) {
 					if math.IsInf(f, 0) && (group.floatMean > 0) == (f > 0) {
 						// The `floatMean` and `s.F` values are `Inf` of the same sign.  They
@@ -2888,8 +2962,13 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 						break
 					}
 				}
+				currentMean := group.floatMean + group.floatKahanC
+				group.floatMean, group.floatKahanC = kahanSumInc(
 					// Divide each side of the `-` by `group.groupCount` to avoid float64 overflows.
-				group.floatMean += f/float64(group.groupCount) - group.floatMean/float64(group.groupCount)
+					f/group.groupCount-currentMean/group.groupCount,
+					group.floatMean,
+					group.floatKahanC,
+				)
 			}
 
 		case parser.GROUP:
@@ -2912,7 +2991,7 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 			if h == nil { // Ignore native histograms.
 				group.groupCount++
 				delta := f - group.floatMean
-				group.floatMean += delta / float64(group.groupCount)
+				group.floatMean += delta / group.groupCount
 				group.floatValue += delta * (f - group.floatMean)
 			}
 
@@ -2938,20 +3017,25 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 				annos.Add(annotations.NewMixedFloatsHistogramsAggWarning(e.Expr.PositionRange()))
 				continue
 			}
-			if aggr.hasHistogram {
+			switch {
+			case aggr.incompatibleHistograms:
+				continue
+			case aggr.hasHistogram:
 				aggr.histogramValue = aggr.histogramValue.Compact(0)
-			} else {
+			case aggr.incrementalMean:
-				aggr.floatValue = aggr.floatMean
+				aggr.floatValue = aggr.floatMean + aggr.floatKahanC
+			default:
+				aggr.floatValue = (aggr.floatValue + aggr.floatKahanC) / aggr.groupCount
 			}
 
 		case parser.COUNT:
-			aggr.floatValue = float64(aggr.groupCount)
+			aggr.floatValue = aggr.groupCount
 
 		case parser.STDVAR:
-			aggr.floatValue /= float64(aggr.groupCount)
+			aggr.floatValue /= aggr.groupCount
 
 		case parser.STDDEV:
-			aggr.floatValue = math.Sqrt(aggr.floatValue / float64(aggr.groupCount))
+			aggr.floatValue = math.Sqrt(aggr.floatValue / aggr.groupCount)
 
 		case parser.QUANTILE:
 			aggr.floatValue = quantile(q, aggr.heap)
@@ -2962,10 +3046,13 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 				annos.Add(annotations.NewMixedFloatsHistogramsAggWarning(e.Expr.PositionRange()))
 				continue
 			}
-			if aggr.hasHistogram {
+			switch {
+			case aggr.incompatibleHistograms:
+				continue
+			case aggr.hasHistogram:
 				aggr.histogramValue.Compact(0)
-			} else {
+			default:
-				aggr.floatValue += aggr.floatMean // Add Kahan summation compensating term.
+				aggr.floatValue += aggr.floatKahanC
 			}
 		default:
 			// For other aggregations, we already have the right value.
@@ -2973,6 +3060,7 @@ func (ev *evaluator) aggregation(e *parser.AggregateExpr, q float64, inputMatrix
 
 		ss := &outputMatrix[ri]
 		addToSeries(ss, enh.Ts, aggr.floatValue, aggr.histogramValue, numSteps)
+		ss.DropName = inputMatrix[ri].DropName
 	}
 
 	return annos
@@ -2999,7 +3087,7 @@ seriesLoop:
 		if !ok {
 			continue
 		}
-		s = Sample{Metric: inputMatrix[si].Metric, F: f}
+		s = Sample{Metric: inputMatrix[si].Metric, F: f, DropName: inputMatrix[si].DropName}
 
 		group := &groups[seriesToResult[si]]
 		// Initialize this group if it's the first time we've seen it.
@@ -3083,16 +3171,16 @@ seriesLoop:
 		mat = make(Matrix, 0, len(groups))
 	}
 
-	add := func(lbls labels.Labels, f float64) {
+	add := func(lbls labels.Labels, f float64, dropName bool) {
 		// If this could be an instant query, add directly to the matrix so the result is in consistent order.
 		if ev.endTimestamp == ev.startTimestamp {
-			mat = append(mat, Series{Metric: lbls, Floats: []FPoint{{T: enh.Ts, F: f}}})
+			mat = append(mat, Series{Metric: lbls, Floats: []FPoint{{T: enh.Ts, F: f}}, DropName: dropName})
 		} else {
 			// Otherwise the results are added into seriess elements.
 			hash := lbls.Hash()
 			ss, ok := seriess[hash]
 			if !ok {
-				ss = Series{Metric: lbls}
+				ss = Series{Metric: lbls, DropName: dropName}
 			}
 			addToSeries(&ss, enh.Ts, f, nil, numSteps)
 			seriess[hash] = ss
@@ -3109,7 +3197,7 @@ seriesLoop:
 				sort.Sort(sort.Reverse(aggr.heap))
 			}
 			for _, v := range aggr.heap {
-				add(v.Metric, v.F)
+				add(v.Metric, v.F, v.DropName)
 			}
 
 		case parser.BOTTOMK:
@@ -3118,12 +3206,12 @@ seriesLoop:
 				sort.Sort(sort.Reverse((*vectorByReverseValueHeap)(&aggr.heap)))
 			}
 			for _, v := range aggr.heap {
-				add(v.Metric, v.F)
+				add(v.Metric, v.F, v.DropName)
 			}
 
 		case parser.LIMITK, parser.LIMIT_RATIO:
 			for _, v := range aggr.heap {
-				add(v.Metric, v.F)
+				add(v.Metric, v.F, v.DropName)
 			}
 		}
 	}
@@ -3131,7 +3219,7 @@ seriesLoop:
 	return mat, annos
 }
 
-// aggregationK evaluates count_values on vec.
+// aggregationCountValues evaluates count_values on vec.
 // Outputs as many series per group as there are values in the input.
 func (ev *evaluator) aggregationCountValues(e *parser.AggregateExpr, grouping []string, valueLabel string, vec Vector, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 	type groupCount struct {
@@ -3175,6 +3263,30 @@ func (ev *evaluator) aggregationCountValues(e *parser.AggregateExpr, grouping []
 	return enh.Out, nil
 }
 
+func (ev *evaluator) cleanupMetricLabels(v parser.Value) {
+	if v.Type() == parser.ValueTypeMatrix {
+		mat := v.(Matrix)
+		for i := range mat {
+			if mat[i].DropName {
+				mat[i].Metric = mat[i].Metric.DropMetricName()
+			}
+		}
+		if mat.ContainsSameLabelset() {
+			ev.errorf("vector cannot contain metrics with the same labelset")
+		}
+	} else if v.Type() == parser.ValueTypeVector {
+		vec := v.(Vector)
+		for i := range vec {
+			if vec[i].DropName {
+				vec[i].Metric = vec[i].Metric.DropMetricName()
+			}
+		}
+		if vec.ContainsSameLabelset() {
+			ev.errorf("vector cannot contain metrics with the same labelset")
+		}
+	}
+}
+
 func addToSeries(ss *Series, ts int64, f float64, h *histogram.FloatHistogram, numSteps int) {
 	if h == nil {
 		if ss.Floats == nil {
@@ -3485,14 +3597,14 @@ func makeInt64Pointer(val int64) *int64 {
 	return valp
 }
 
-// Add RatioSampler interface to allow unit-testing (previously: Randomizer).
+// RatioSampler allows unit-testing (previously: Randomizer).
 type RatioSampler interface {
 	// Return this sample "offset" between [0.0, 1.0]
 	sampleOffset(ts int64, sample *Sample) float64
 	AddRatioSample(r float64, sample *Sample) bool
 }
 
-// Use Hash(labels.String()) / maxUint64 as a "deterministic"
+// HashRatioSampler uses Hash(labels.String()) / maxUint64 as a "deterministic"
 // value in [0.0, 1.0].
 type HashRatioSampler struct{}
 

promql/engine_test.go

@@ -17,8 +17,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"math"
-	"os"
 	"sort"
 	"strconv"
 	"sync"
@@ -56,14 +54,7 @@ func TestMain(m *testing.M) {
 func TestQueryConcurrency(t *testing.T) {
 	maxConcurrency := 10
 
-	dir, err := os.MkdirTemp("", "test_concurrency")
+	queryTracker := promql.NewActiveQueryTracker(t.TempDir(), maxConcurrency, nil)
-	require.NoError(t, err)
-	defer os.RemoveAll(dir)
-	queryTracker := promql.NewActiveQueryTracker(dir, maxConcurrency, nil)
-	t.Cleanup(func() {
-		require.NoError(t, queryTracker.Close())
-	})
-
 	opts := promql.EngineOpts{
 		Logger:             nil,
 		Reg:                nil,
@@ -71,15 +62,17 @@ func TestQueryConcurrency(t *testing.T) {
 		Timeout:            100 * time.Second,
 		ActiveQueryTracker: queryTracker,
 	}
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 
-	engine := promql.NewEngine(opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
-	defer cancelCtx()
+	t.Cleanup(cancelCtx)
 
 	block := make(chan struct{})
 	processing := make(chan struct{})
 	done := make(chan int)
-	defer close(done)
+	t.Cleanup(func() {
+		close(done)
+	})
 
 	f := func(context.Context) error {
 		select {
@@ -164,7 +157,7 @@ func TestQueryTimeout(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    5 * time.Millisecond,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
 	defer cancelCtx()
 
@@ -189,7 +182,7 @@ func TestQueryCancel(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
 	defer cancelCtx()
 
@@ -263,7 +256,7 @@ func TestQueryError(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	errStorage := promql.ErrStorage{errors.New("storage error")}
 	queryable := storage.QueryableFunc(func(mint, maxt int64) (storage.Querier, error) {
 		return &errQuerier{err: errStorage}, nil
@@ -597,7 +590,7 @@ func TestSelectHintsSetCorrectly(t *testing.T) {
 		},
 	} {
 		t.Run(tc.query, func(t *testing.T) {
-			engine := promql.NewEngine(opts)
+			engine := promqltest.NewTestEngineWithOpts(t, opts)
 			hintsRecorder := &noopHintRecordingQueryable{}
 
 			var (
@@ -628,7 +621,7 @@ func TestEngineShutdown(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
 
 	block := make(chan struct{})
@@ -764,7 +757,7 @@ load 10s
 		t.Run(fmt.Sprintf("%d query=%s", i, c.Query), func(t *testing.T) {
 			var err error
 			var qry promql.Query
-			engine := newTestEngine()
+			engine := newTestEngine(t)
 			if c.Interval == 0 {
 				qry, err = engine.NewInstantQuery(context.Background(), storage, nil, c.Query, c.Start)
 			} else {
@@ -1306,7 +1299,7 @@ load 10s
 	for _, c := range cases {
 		t.Run(c.Query, func(t *testing.T) {
 			opts := promql.NewPrometheusQueryOpts(true, 0)
-			engine := promqltest.NewTestEngine(true, 0, promqltest.DefaultMaxSamplesPerQuery)
+			engine := promqltest.NewTestEngine(t, true, 0, promqltest.DefaultMaxSamplesPerQuery)
 
 			runQuery := func(expErr error) *stats.Statistics {
 				var err error
@@ -1333,7 +1326,7 @@ load 10s
 			if c.SkipMaxCheck {
 				return
 			}
-			engine = promqltest.NewTestEngine(true, 0, stats.Samples.PeakSamples-1)
+			engine = promqltest.NewTestEngine(t, true, 0, stats.Samples.PeakSamples-1)
 			runQuery(promql.ErrTooManySamples(env))
 		})
 	}
@@ -1486,7 +1479,7 @@ load 10s
 
 	for _, c := range cases {
 		t.Run(c.Query, func(t *testing.T) {
-			engine := newTestEngine()
+			engine := newTestEngine(t)
 			testFunc := func(expError error) {
 				var err error
 				var qry promql.Query
@@ -1507,18 +1500,18 @@ load 10s
 			}
 
 			// Within limit.
-			engine = promqltest.NewTestEngine(false, 0, c.MaxSamples)
+			engine = promqltest.NewTestEngine(t, false, 0, c.MaxSamples)
 			testFunc(nil)
 
 			// Exceeding limit.
-			engine = promqltest.NewTestEngine(false, 0, c.MaxSamples-1)
+			engine = promqltest.NewTestEngine(t, false, 0, c.MaxSamples-1)
 			testFunc(promql.ErrTooManySamples(env))
 		})
 	}
 }
 
 func TestAtModifier(t *testing.T) {
-	engine := newTestEngine()
+	engine := newTestEngine(t)
 	storage := promqltest.LoadedStorage(t, `
 load 10s
   metric{job="1"} 0+1x1000
@@ -1715,6 +1708,7 @@ load 1ms
 						{F: 3600, T: 7 * 60 * 1000},
 					},
 					Metric:   labels.EmptyLabels(),
+					DropName: true,
 				},
 			},
 		},
@@ -1932,18 +1926,22 @@ func TestSubquerySelector(t *testing.T) {
 							promql.Series{
 								Floats:   []promql.FPoint{{F: 3, T: 7985000}, {F: 3, T: 7990000}, {F: 3, T: 7995000}, {F: 3, T: 8000000}},
 								Metric:   labels.FromStrings("job", "api-server", "instance", "0", "group", "canary"),
+								DropName: true,
 							},
 							promql.Series{
 								Floats:   []promql.FPoint{{F: 4, T: 7985000}, {F: 4, T: 7990000}, {F: 4, T: 7995000}, {F: 4, T: 8000000}},
 								Metric:   labels.FromStrings("job", "api-server", "instance", "1", "group", "canary"),
+								DropName: true,
 							},
 							promql.Series{
 								Floats:   []promql.FPoint{{F: 1, T: 7985000}, {F: 1, T: 7990000}, {F: 1, T: 7995000}, {F: 1, T: 8000000}},
 								Metric:   labels.FromStrings("job", "api-server", "instance", "0", "group", "production"),
+								DropName: true,
 							},
 							promql.Series{
 								Floats:   []promql.FPoint{{F: 2, T: 7985000}, {F: 2, T: 7990000}, {F: 2, T: 7995000}, {F: 2, T: 8000000}},
 								Metric:   labels.FromStrings("job", "api-server", "instance", "1", "group", "production"),
+								DropName: true,
 							},
 						},
 						nil,
@@ -1996,7 +1994,7 @@ func TestSubquerySelector(t *testing.T) {
 		},
 	} {
 		t.Run("", func(t *testing.T) {
-			engine := newTestEngine()
+			engine := newTestEngine(t)
 			storage := promqltest.LoadedStorage(t, tst.loadString)
 			t.Cleanup(func() { storage.Close() })
 
@@ -2045,7 +2043,7 @@ func TestQueryLogger_basic(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 
 	queryExec := func() {
 		ctx, cancelCtx := context.WithCancel(context.Background())
@@ -2096,7 +2094,7 @@ func TestQueryLogger_fields(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 
 	f1 := NewFakeQueryLogger()
 	engine.SetQueryLogger(f1)
@@ -2125,7 +2123,7 @@ func TestQueryLogger_error(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 
 	f1 := NewFakeQueryLogger()
 	engine.SetQueryLogger(f1)
@@ -3008,7 +3006,7 @@ func TestEngineOptsValidation(t *testing.T) {
 	}
 
 	for _, c := range cases {
-		eng := promql.NewEngine(c.opts)
+		eng := promqltest.NewTestEngineWithOpts(t, c.opts)
 		_, err1 := eng.NewInstantQuery(context.Background(), nil, nil, c.query, time.Unix(10, 0))
 		_, err2 := eng.NewRangeQuery(context.Background(), nil, nil, c.query, time.Unix(0, 0), time.Unix(10, 0), time.Second)
 		if c.fail {
@@ -3022,7 +3020,7 @@ func TestEngineOptsValidation(t *testing.T) {
 }
 
 func TestInstantQueryWithRangeVectorSelector(t *testing.T) {
-	engine := newTestEngine()
+	engine := newTestEngine(t)
 
 	baseT := timestamp.Time(0)
 	storage := promqltest.LoadedStorage(t, `
@@ -3097,217 +3095,6 @@ func TestInstantQueryWithRangeVectorSelector(t *testing.T) {
 	}
 }
 
-func TestNativeHistogram_Sum_Count_Add_AvgOperator(t *testing.T) {
-	// TODO(codesome): Integrate histograms into the PromQL testing framework
-	// and write more tests there.
-	cases := []struct {
-		histograms  []histogram.Histogram
-		expected    histogram.FloatHistogram
-		expectedAvg histogram.FloatHistogram
-	}{
-		{
-			histograms: []histogram.Histogram{
-				{
-					CounterResetHint: histogram.GaugeType,
-					Schema:           0,
-					Count:            25,
-					Sum:              1234.5,
-					ZeroThreshold:    0.001,
-					ZeroCount:        4,
-					PositiveSpans: []histogram.Span{
-						{Offset: 0, Length: 2},
-						{Offset: 1, Length: 2},
-					},
-					PositiveBuckets: []int64{1, 1, -1, 0},
-					NegativeSpans: []histogram.Span{
-						{Offset: 0, Length: 2},
-						{Offset: 2, Length: 2},
-					},
-					NegativeBuckets: []int64{2, 2, -3, 8},
-				},
-				{
-					CounterResetHint: histogram.GaugeType,
-					Schema:           0,
-					Count:            41,
-					Sum:              2345.6,
-					ZeroThreshold:    0.001,
-					ZeroCount:        5,
-					PositiveSpans: []histogram.Span{
-						{Offset: 0, Length: 4},
-						{Offset: 0, Length: 0},
-						{Offset: 0, Length: 3},
-					},
-					PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
-					NegativeSpans: []histogram.Span{
-						{Offset: 1, Length: 4},
-						{Offset: 2, Length: 0},
-						{Offset: 2, Length: 3},
-					},
-					NegativeBuckets: []int64{1, 3, -2, 5, -2, 0, -3},
-				},
-				{
-					CounterResetHint: histogram.GaugeType,
-					Schema:           0,
-					Count:            41,
-					Sum:              1111.1,
-					ZeroThreshold:    0.001,
-					ZeroCount:        5,
-					PositiveSpans: []histogram.Span{
-						{Offset: 0, Length: 4},
-						{Offset: 0, Length: 0},
-						{Offset: 0, Length: 3},
-					},
-					PositiveBuckets: []int64{1, 2, -2, 1, -1, 0, 0},
-					NegativeSpans: []histogram.Span{
-						{Offset: 1, Length: 4},
-						{Offset: 2, Length: 0},
-						{Offset: 2, Length: 3},
-					},
-					NegativeBuckets: []int64{1, 3, -2, 5, -2, 0, -3},
-				},
-				{
-					CounterResetHint: histogram.GaugeType,
-					Schema:           1, // Everything is 0 just to make the count 4 so avg has nicer numbers.
-				},
-			},
-			expected: histogram.FloatHistogram{
-				CounterResetHint: histogram.GaugeType,
-				Schema:           0,
-				ZeroThreshold:    0.001,
-				ZeroCount:        14,
-				Count:            107,
-				Sum:              4691.2,
-				PositiveSpans: []histogram.Span{
-					{Offset: 0, Length: 7},
-				},
-				PositiveBuckets: []float64{3, 8, 2, 5, 3, 2, 2},
-				NegativeSpans: []histogram.Span{
-					{Offset: 0, Length: 6},
-					{Offset: 3, Length: 3},
-				},
-				NegativeBuckets: []float64{2, 6, 8, 4, 15, 9, 10, 10, 4},
-			},
-			expectedAvg: histogram.FloatHistogram{
-				CounterResetHint: histogram.GaugeType,
-				Schema:           0,
-				ZeroThreshold:    0.001,
-				ZeroCount:        3.5,
-				Count:            26.75,
-				Sum:              1172.8,
-				PositiveSpans: []histogram.Span{
-					{Offset: 0, Length: 7},
-				},
-				PositiveBuckets: []float64{0.75, 2, 0.5, 1.25, 0.75, 0.5, 0.5},
-				NegativeSpans: []histogram.Span{
-					{Offset: 0, Length: 6},
-					{Offset: 3, Length: 3},
-				},
-				NegativeBuckets: []float64{0.5, 1.5, 2, 1, 3.75, 2.25, 2.5, 2.5, 1},
-			},
-		},
-	}
-
-	idx0 := int64(0)
-	for _, c := range cases {
-		for _, floatHisto := range []bool{true, false} {
-			t.Run(fmt.Sprintf("floatHistogram=%t %d", floatHisto, idx0), func(t *testing.T) {
-				storage := teststorage.New(t)
-				t.Cleanup(func() { storage.Close() })
-
-				seriesName := "sparse_histogram_series"
-				seriesNameOverTime := "sparse_histogram_series_over_time"
-
-				engine := newTestEngine()
-
-				ts := idx0 * int64(10*time.Minute/time.Millisecond)
-				app := storage.Appender(context.Background())
-				_, err := app.Append(0, labels.FromStrings("__name__", "float_series", "idx", "0"), ts, 42)
-				require.NoError(t, err)
-				for idx1, h := range c.histograms {
-					lbls := labels.FromStrings("__name__", seriesName, "idx", strconv.Itoa(idx1))
-					// Since we mutate h later, we need to create a copy here.
-					var err error
-					if floatHisto {
-						_, err = app.AppendHistogram(0, lbls, ts, nil, h.Copy().ToFloat(nil))
-					} else {
-						_, err = app.AppendHistogram(0, lbls, ts, h.Copy(), nil)
-					}
-					require.NoError(t, err)
-
-					lbls = labels.FromStrings("__name__", seriesNameOverTime)
-					newTs := ts + int64(idx1)*int64(time.Minute/time.Millisecond)
-					// Since we mutate h later, we need to create a copy here.
-					if floatHisto {
-						_, err = app.AppendHistogram(0, lbls, newTs, nil, h.Copy().ToFloat(nil))
-					} else {
-						_, err = app.AppendHistogram(0, lbls, newTs, h.Copy(), nil)
-					}
-					require.NoError(t, err)
-				}
-				require.NoError(t, app.Commit())
-
-				queryAndCheck := func(queryString string, ts int64, exp promql.Vector) {
-					qry, err := engine.NewInstantQuery(context.Background(), storage, nil, queryString, timestamp.Time(ts))
-					require.NoError(t, err)
-
-					res := qry.Exec(context.Background())
-					require.NoError(t, res.Err)
-					require.Empty(t, res.Warnings)
-
-					vector, err := res.Vector()
-					require.NoError(t, err)
-
-					testutil.RequireEqual(t, exp, vector)
-				}
-				queryAndCheckAnnotations := func(queryString string, ts int64, expWarnings annotations.Annotations) {
-					qry, err := engine.NewInstantQuery(context.Background(), storage, nil, queryString, timestamp.Time(ts))
-					require.NoError(t, err)
-
-					res := qry.Exec(context.Background())
-					require.NoError(t, res.Err)
-					require.Equal(t, expWarnings, res.Warnings)
-				}
-
-				// sum().
-				queryString := fmt.Sprintf("sum(%s)", seriesName)
-				queryAndCheck(queryString, ts, []promql.Sample{{T: ts, H: &c.expected, Metric: labels.EmptyLabels()}})
-
-				queryString = `sum({idx="0"})`
-				var annos annotations.Annotations
-				annos.Add(annotations.NewMixedFloatsHistogramsAggWarning(posrange.PositionRange{Start: 4, End: 13}))
-				queryAndCheckAnnotations(queryString, ts, annos)
-
-				// + operator.
-				queryString = fmt.Sprintf(`%s{idx="0"}`, seriesName)
-				for idx := 1; idx < len(c.histograms); idx++ {
-					queryString += fmt.Sprintf(` + ignoring(idx) %s{idx="%d"}`, seriesName, idx)
-				}
-				queryAndCheck(queryString, ts, []promql.Sample{{T: ts, H: &c.expected, Metric: labels.EmptyLabels()}})
-
-				// count().
-				queryString = fmt.Sprintf("count(%s)", seriesName)
-				queryAndCheck(queryString, ts, []promql.Sample{{T: ts, F: 4, Metric: labels.EmptyLabels()}})
-
-				// avg().
-				queryString = fmt.Sprintf("avg(%s)", seriesName)
-				queryAndCheck(queryString, ts, []promql.Sample{{T: ts, H: &c.expectedAvg, Metric: labels.EmptyLabels()}})
-
-				offset := int64(len(c.histograms) - 1)
-				newTs := ts + offset*int64(time.Minute/time.Millisecond)
-
-				// sum_over_time().
-				queryString = fmt.Sprintf("sum_over_time(%s[%dm:1m])", seriesNameOverTime, offset)
-				queryAndCheck(queryString, newTs, []promql.Sample{{T: newTs, H: &c.expected, Metric: labels.EmptyLabels()}})
-
-				// avg_over_time().
-				queryString = fmt.Sprintf("avg_over_time(%s[%dm:1m])", seriesNameOverTime, offset)
-				queryAndCheck(queryString, newTs, []promql.Sample{{T: newTs, H: &c.expectedAvg, Metric: labels.EmptyLabels()}})
-			})
-			idx0++
-		}
-	}
-}
-
 func TestNativeHistogram_SubOperator(t *testing.T) {
 	// TODO(codesome): Integrate histograms into the PromQL testing framework
 	// and write more tests there.
@@ -3487,7 +3274,7 @@ func TestNativeHistogram_SubOperator(t *testing.T) {
 	for _, c := range cases {
 		for _, floatHisto := range []bool{true, false} {
 			t.Run(fmt.Sprintf("floatHistogram=%t %d", floatHisto, idx0), func(t *testing.T) {
-				engine := newTestEngine()
+				engine := newTestEngine(t)
 				storage := teststorage.New(t)
 				t.Cleanup(func() { storage.Close() })
 
@@ -3543,171 +3330,6 @@ func TestNativeHistogram_SubOperator(t *testing.T) {
 	}
 }
 
-func TestNativeHistogram_MulDivOperator(t *testing.T) {
-	// TODO(codesome): Integrate histograms into the PromQL testing framework
-	// and write more tests there.
-	originalHistogram := histogram.Histogram{
-		Schema:        0,
-		Count:         21,
-		Sum:           33,
-		ZeroThreshold: 0.001,
-		ZeroCount:     3,
-		PositiveSpans: []histogram.Span{
-			{Offset: 0, Length: 3},
-		},
-		PositiveBuckets: []int64{3, 0, 0},
-		NegativeSpans: []histogram.Span{
-			{Offset: 0, Length: 3},
-		},
-		NegativeBuckets: []int64{3, 0, 0},
-	}
-
-	cases := []struct {
-		scalar      float64
-		histogram   histogram.Histogram
-		expectedMul histogram.FloatHistogram
-		expectedDiv histogram.FloatHistogram
-	}{
-		{
-			scalar:    3,
-			histogram: originalHistogram,
-			expectedMul: histogram.FloatHistogram{
-				Schema:        0,
-				Count:         63,
-				Sum:           99,
-				ZeroThreshold: 0.001,
-				ZeroCount:     9,
-				PositiveSpans: []histogram.Span{
-					{Offset: 0, Length: 3},
-				},
-				PositiveBuckets: []float64{9, 9, 9},
-				NegativeSpans: []histogram.Span{
-					{Offset: 0, Length: 3},
-				},
-				NegativeBuckets: []float64{9, 9, 9},
-			},
-			expectedDiv: histogram.FloatHistogram{
-				Schema:        0,
-				Count:         7,
-				Sum:           11,
-				ZeroThreshold: 0.001,
-				ZeroCount:     1,
-				PositiveSpans: []histogram.Span{
-					{Offset: 0, Length: 3},
-				},
-				PositiveBuckets: []float64{1, 1, 1},
-				NegativeSpans: []histogram.Span{
-					{Offset: 0, Length: 3},
-				},
-				NegativeBuckets: []float64{1, 1, 1},
-			},
-		},
-		{
-			scalar:    0,
-			histogram: originalHistogram,
-			expectedMul: histogram.FloatHistogram{
-				Schema:        0,
-				Count:         0,
-				Sum:           0,
-				ZeroThreshold: 0.001,
-				ZeroCount:     0,
-				PositiveSpans: []histogram.Span{
-					{Offset: 0, Length: 3},
-				},
-				PositiveBuckets: []float64{0, 0, 0},
-				NegativeSpans: []histogram.Span{
-					{Offset: 0, Length: 3},
-				},
-				NegativeBuckets: []float64{0, 0, 0},
-			},
-			expectedDiv: histogram.FloatHistogram{
-				Schema:        0,
-				Count:         math.Inf(1),
-				Sum:           math.Inf(1),
-				ZeroThreshold: 0.001,
-				ZeroCount:     math.Inf(1),
-				PositiveSpans: []histogram.Span{
-					{Offset: 0, Length: 3},
-				},
-				PositiveBuckets: []float64{math.Inf(1), math.Inf(1), math.Inf(1)},
-				NegativeSpans: []histogram.Span{
-					{Offset: 0, Length: 3},
-				},
-				NegativeBuckets: []float64{math.Inf(1), math.Inf(1), math.Inf(1)},
-			},
-		},
-	}
-
-	idx0 := int64(0)
-	for _, c := range cases {
-		for _, floatHisto := range []bool{true, false} {
-			t.Run(fmt.Sprintf("floatHistogram=%t %d", floatHisto, idx0), func(t *testing.T) {
-				storage := teststorage.New(t)
-				t.Cleanup(func() { storage.Close() })
-
-				seriesName := "sparse_histogram_series"
-				floatSeriesName := "float_series"
-
-				engine := newTestEngine()
-
-				ts := idx0 * int64(10*time.Minute/time.Millisecond)
-				app := storage.Appender(context.Background())
-				h := c.histogram
-				lbls := labels.FromStrings("__name__", seriesName)
-				// Since we mutate h later, we need to create a copy here.
-				var err error
-				if floatHisto {
-					_, err = app.AppendHistogram(0, lbls, ts, nil, h.Copy().ToFloat(nil))
-				} else {
-					_, err = app.AppendHistogram(0, lbls, ts, h.Copy(), nil)
-				}
-				require.NoError(t, err)
-				_, err = app.Append(0, labels.FromStrings("__name__", floatSeriesName), ts, c.scalar)
-				require.NoError(t, err)
-				require.NoError(t, app.Commit())
-
-				queryAndCheck := func(queryString string, exp promql.Vector) {
-					qry, err := engine.NewInstantQuery(context.Background(), storage, nil, queryString, timestamp.Time(ts))
-					require.NoError(t, err)
-
-					res := qry.Exec(context.Background())
-					require.NoError(t, res.Err)
-
-					vector, err := res.Vector()
-					require.NoError(t, err)
-
-					testutil.RequireEqual(t, exp, vector)
-				}
-
-				// histogram * scalar.
-				queryString := fmt.Sprintf(`%s * %f`, seriesName, c.scalar)
-				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
-
-				// scalar * histogram.
-				queryString = fmt.Sprintf(`%f * %s`, c.scalar, seriesName)
-				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
-
-				// histogram * float.
-				queryString = fmt.Sprintf(`%s * %s`, seriesName, floatSeriesName)
-				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
-
-				// float * histogram.
-				queryString = fmt.Sprintf(`%s * %s`, floatSeriesName, seriesName)
-				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedMul, Metric: labels.EmptyLabels()}})
-
-				// histogram / scalar.
-				queryString = fmt.Sprintf(`%s / %f`, seriesName, c.scalar)
-				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedDiv, Metric: labels.EmptyLabels()}})
-
-				// histogram / float.
-				queryString = fmt.Sprintf(`%s / %s`, seriesName, floatSeriesName)
-				queryAndCheck(queryString, []promql.Sample{{T: ts, H: &c.expectedDiv, Metric: labels.EmptyLabels()}})
-			})
-			idx0++
-		}
-	}
-}
-
 func TestQueryLookbackDelta(t *testing.T) {
 	var (
 		load = `load 5m
@@ -3771,7 +3393,7 @@ metric 0 1 2
 	for _, c := range cases {
 		c := c
 		t.Run(c.name, func(t *testing.T) {
-			engine := promqltest.NewTestEngine(false, c.engineLookback, promqltest.DefaultMaxSamplesPerQuery)
+			engine := promqltest.NewTestEngine(t, false, c.engineLookback, promqltest.DefaultMaxSamplesPerQuery)
 			storage := promqltest.LoadedStorage(t, load)
 			t.Cleanup(func() { storage.Close() })
 
@@ -3797,3 +3419,62 @@ func makeInt64Pointer(val int64) *int64 {
 	*valp = val
 	return valp
 }
+
+func TestHistogramCopyFromIteratorRegression(t *testing.T) {
+	// Loading the following histograms creates two chunks because there's a
+	// counter reset. Not only the counter is lower in the last histogram
+	// but also there's missing buckets.
+	// This in turns means that chunk iterators will have different spans.
+	load := `load 1m
+histogram {{sum:4 count:4 buckets:[2 2]}} {{sum:6 count:6 buckets:[3 3]}} {{sum:1 count:1 buckets:[1]}}
+`
+	storage := promqltest.LoadedStorage(t, load)
+	t.Cleanup(func() { storage.Close() })
+	engine := promqltest.NewTestEngine(t, false, 0, promqltest.DefaultMaxSamplesPerQuery)
+
+	verify := func(t *testing.T, qry promql.Query, expected []histogram.FloatHistogram) {
+		res := qry.Exec(context.Background())
+		require.NoError(t, res.Err)
+
+		m, ok := res.Value.(promql.Matrix)
+		require.True(t, ok)
+
+		require.Len(t, m, 1)
+		series := m[0]
+
+		require.Empty(t, series.Floats)
+		require.Len(t, series.Histograms, len(expected))
+		for i, e := range expected {
+			series.Histograms[i].H.CounterResetHint = histogram.UnknownCounterReset // Don't care.
+			require.Equal(t, &e, series.Histograms[i].H)
+		}
+	}
+
+	qry, err := engine.NewRangeQuery(context.Background(), storage, nil, "increase(histogram[60s])", time.Unix(0, 0), time.Unix(0, 0).Add(1*time.Minute), time.Minute)
+	require.NoError(t, err)
+	verify(t, qry, []histogram.FloatHistogram{
+		{
+			Count:           2,
+			Sum:             2,                                        // Increase from 4 to 6 is 2.
+			PositiveSpans:   []histogram.Span{{Offset: 0, Length: 2}}, // Two buckets changed between the first and second histogram.
+			PositiveBuckets: []float64{1, 1},                          // Increase from 2 to 3 is 1 in both buckets.
+		},
+	})
+
+	qry, err = engine.NewInstantQuery(context.Background(), storage, nil, "histogram[60s]", time.Unix(0, 0).Add(2*time.Minute))
+	require.NoError(t, err)
+	verify(t, qry, []histogram.FloatHistogram{
+		{
+			Count:           6,
+			Sum:             6,
+			PositiveSpans:   []histogram.Span{{Offset: 0, Length: 2}},
+			PositiveBuckets: []float64{3, 3},
+		},
+		{
+			Count:           1,
+			Sum:             1,
+			PositiveSpans:   []histogram.Span{{Offset: 0, Length: 1}},
+			PositiveBuckets: []float64{1},
+		},
+	})
+}

promql/functions.go

@@ -14,6 +14,7 @@
 package promql
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"math"
@@ -97,9 +98,10 @@ func extrapolatedRate(vals []parser.Value, args parser.Expressions, enh *EvalNod
 		lastT = samples.Histograms[numSamplesMinusOne].T
 		var newAnnos annotations.Annotations
 		resultHistogram, newAnnos = histogramRate(samples.Histograms, isCounter, metricName, args[0].PositionRange())
+		annos.Merge(newAnnos)
 		if resultHistogram == nil {
 			// The histograms are not compatible with each other.
-			return enh.Out, annos.Merge(newAnnos)
+			return enh.Out, annos
 		}
 	case len(samples.Floats) > 1:
 		numSamplesMinusOne = len(samples.Floats) - 1
@@ -178,17 +180,29 @@ func extrapolatedRate(vals []parser.Value, args parser.Expressions, enh *EvalNod
 // Otherwise, it returns the calculated histogram and an empty annotation.
 func histogramRate(points []HPoint, isCounter bool, metricName string, pos posrange.PositionRange) (*histogram.FloatHistogram, annotations.Annotations) {
 	prev := points[0].H
+	usingCustomBuckets := prev.UsesCustomBuckets()
 	last := points[len(points)-1].H
 	if last == nil {
 		return nil, annotations.New().Add(annotations.NewMixedFloatsHistogramsWarning(metricName, pos))
 	}
+
 	minSchema := prev.Schema
 	if last.Schema < minSchema {
 		minSchema = last.Schema
 	}
 
+	if last.UsesCustomBuckets() != usingCustomBuckets {
+		return nil, annotations.New().Add(annotations.NewMixedExponentialCustomHistogramsWarning(metricName, pos))
+	}
+
 	var annos annotations.Annotations
 
+	// We check for gauge type histograms in the loop below, but the loop below does not run on the first and last point,
+	// so check the first and last point now.
+	if isCounter && (prev.CounterResetHint == histogram.GaugeType || last.CounterResetHint == histogram.GaugeType) {
+		annos.Add(annotations.NewNativeHistogramNotCounterWarning(metricName, pos))
+	}
+
 	// First iteration to find out two things:
 	// - What's the smallest relevant schema?
 	// - Are all data points histograms?
@@ -208,6 +222,9 @@ func histogramRate(points []HPoint, isCounter bool, metricName string, pos posra
 		if curr.Schema < minSchema {
 			minSchema = curr.Schema
 		}
+		if curr.UsesCustomBuckets() != usingCustomBuckets {
+			return nil, annotations.New().Add(annotations.NewMixedExponentialCustomHistogramsWarning(metricName, pos))
+		}
 	}
 
 	h := last.CopyToSchema(minSchema)
@@ -241,7 +258,7 @@ func histogramRate(points []HPoint, isCounter bool, metricName string, pos posra
 	}
 
 	h.CounterResetHint = histogram.GaugeType
-	return h.Compact(0), nil
+	return h.Compact(0), annos
 }
 
 // === delta(Matrix parser.ValueTypeMatrix) (Vector, Annotations) ===
@@ -390,17 +407,22 @@ func funcSortDesc(vals []parser.Value, args parser.Expressions, enh *EvalNodeHel
 
 // === sort_by_label(vector parser.ValueTypeVector, label parser.ValueTypeString...) (Vector, Annotations) ===
 func funcSortByLabel(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
-	// In case the labels are the same, NaN should sort to the bottom, so take
+	// First, sort by the full label set. This ensures a consistent ordering in case sorting by the
-	// ascending sort with NaN first and reverse it.
+	// labels provided as arguments is not conclusive.
-	var anno annotations.Annotations
-	vals[0], anno = funcSort(vals, args, enh)
-	labels := stringSliceFromArgs(args[1:])
 	slices.SortFunc(vals[0].(Vector), func(a, b Sample) int {
-		// Iterate over each given label
+		return labels.Compare(a.Metric, b.Metric)
+	})
+
+	labels := stringSliceFromArgs(args[1:])
+	// Next, sort by the labels provided as arguments.
+	slices.SortFunc(vals[0].(Vector), func(a, b Sample) int {
+		// Iterate over each given label.
 		for _, label := range labels {
 			lv1 := a.Metric.Get(label)
 			lv2 := b.Metric.Get(label)
 
+			// If we encounter multiple samples with the same label values, the sorting which was
+			// performed in the first step will act as a "tie breaker".
 			if lv1 == lv2 {
 				continue
 			}
@@ -415,22 +437,27 @@ func funcSortByLabel(vals []parser.Value, args parser.Expressions, enh *EvalNode
 		return 0
 	})
 
-	return vals[0].(Vector), anno
+	return vals[0].(Vector), nil
 }
 
 // === sort_by_label_desc(vector parser.ValueTypeVector, label parser.ValueTypeString...) (Vector, Annotations) ===
 func funcSortByLabelDesc(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
-	// In case the labels are the same, NaN should sort to the bottom, so take
+	// First, sort by the full label set. This ensures a consistent ordering in case sorting by the
-	// ascending sort with NaN first and reverse it.
+	// labels provided as arguments is not conclusive.
-	var anno annotations.Annotations
-	vals[0], anno = funcSortDesc(vals, args, enh)
-	labels := stringSliceFromArgs(args[1:])
 	slices.SortFunc(vals[0].(Vector), func(a, b Sample) int {
-		// Iterate over each given label
+		return labels.Compare(b.Metric, a.Metric)
+	})
+
+	labels := stringSliceFromArgs(args[1:])
+	// Next, sort by the labels provided as arguments.
+	slices.SortFunc(vals[0].(Vector), func(a, b Sample) int {
+		// Iterate over each given label.
 		for _, label := range labels {
 			lv1 := a.Metric.Get(label)
 			lv2 := b.Metric.Get(label)
 
+			// If we encounter multiple samples with the same label values, the sorting which was
+			// performed in the first step will act as a "tie breaker".
 			if lv1 == lv2 {
 				continue
 			}
@@ -445,21 +472,25 @@ func funcSortByLabelDesc(vals []parser.Value, args parser.Expressions, enh *Eval
 		return 0
 	})
 
-	return vals[0].(Vector), anno
+	return vals[0].(Vector), nil
 }
 
 // === clamp(Vector parser.ValueTypeVector, min, max Scalar) (Vector, Annotations) ===
 func funcClamp(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 	vec := vals[0].(Vector)
-	min := vals[1].(Vector)[0].F
+	minVal := vals[1].(Vector)[0].F
-	max := vals[2].(Vector)[0].F
+	maxVal := vals[2].(Vector)[0].F
-	if max < min {
+	if maxVal < minVal {
 		return enh.Out, nil
 	}
 	for _, el := range vec {
+		if !enh.enableDelayedNameRemoval {
+			el.Metric = el.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: el.Metric.DropMetricName(),
+			Metric:   el.Metric,
-			F:      math.Max(min, math.Min(max, el.F)),
+			F:        math.Max(minVal, math.Min(maxVal, el.F)),
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -468,11 +499,15 @@ func funcClamp(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper
 // === clamp_max(Vector parser.ValueTypeVector, max Scalar) (Vector, Annotations) ===
 func funcClampMax(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 	vec := vals[0].(Vector)
-	max := vals[1].(Vector)[0].F
+	maxVal := vals[1].(Vector)[0].F
 	for _, el := range vec {
+		if !enh.enableDelayedNameRemoval {
+			el.Metric = el.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: el.Metric.DropMetricName(),
+			Metric:   el.Metric,
-			F:      math.Min(max, el.F),
+			F:        math.Min(maxVal, el.F),
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -481,11 +516,15 @@ func funcClampMax(vals []parser.Value, args parser.Expressions, enh *EvalNodeHel
 // === clamp_min(Vector parser.ValueTypeVector, min Scalar) (Vector, Annotations) ===
 func funcClampMin(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 	vec := vals[0].(Vector)
-	min := vals[1].(Vector)[0].F
+	minVal := vals[1].(Vector)[0].F
 	for _, el := range vec {
+		if !enh.enableDelayedNameRemoval {
+			el.Metric = el.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: el.Metric.DropMetricName(),
+			Metric:   el.Metric,
-			F:      math.Max(min, el.F),
+			F:        math.Max(minVal, el.F),
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -506,8 +545,9 @@ func funcRound(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper
 	for _, el := range vec {
 		f := math.Floor(el.F*toNearestInverse+0.5) / toNearestInverse
 		enh.Out = append(enh.Out, Sample{
-			Metric: el.Metric.DropMetricName(),
+			Metric:   el.Metric,
 			F:        f,
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -573,9 +613,28 @@ func funcAvgOverTime(vals []parser.Value, args parser.Expressions, enh *EvalNode
 		return vec, nil
 	}
 	return aggrOverTime(vals, enh, func(s Series) float64 {
-		var mean, count, c float64
+		var (
+			sum, mean, count, kahanC float64
+			incrementalMean          bool
+		)
 		for _, f := range s.Floats {
 			count++
+			if !incrementalMean {
+				newSum, newC := kahanSumInc(f.F, sum, kahanC)
+				// Perform regular mean calculation as long as
+				// the sum doesn't overflow and (in any case)
+				// for the first iteration (even if we start
+				// with ±Inf) to not run into division-by-zero
+				// problems below.
+				if count == 1 || !math.IsInf(newSum, 0) {
+					sum, kahanC = newSum, newC
+					continue
+				}
+				// Handle overflow by reverting to incremental calculation of the mean value.
+				incrementalMean = true
+				mean = sum / (count - 1)
+				kahanC /= count - 1
+			}
 			if math.IsInf(mean, 0) {
 				if math.IsInf(f.F, 0) && (mean > 0) == (f.F > 0) {
 					// The `mean` and `f.F` values are `Inf` of the same sign.  They
@@ -593,13 +652,13 @@ func funcAvgOverTime(vals []parser.Value, args parser.Expressions, enh *EvalNode
 					continue
 				}
 			}
-			mean, c = kahanSumInc(f.F/count-mean/count, mean, c)
+			correctedMean := mean + kahanC
+			mean, kahanC = kahanSumInc(f.F/count-correctedMean/count, mean, kahanC)
 		}
-
+		if incrementalMean {
-		if math.IsInf(mean, 0) {
+			return mean + kahanC
-			return mean
 		}
-		return mean + c
+		return (sum + kahanC) / count
 	}), nil
 }
 
@@ -665,13 +724,13 @@ func funcMaxOverTime(vals []parser.Value, args parser.Expressions, enh *EvalNode
 		return enh.Out, nil
 	}
 	return aggrOverTime(vals, enh, func(s Series) float64 {
-		max := s.Floats[0].F
+		maxVal := s.Floats[0].F
 		for _, f := range s.Floats {
-			if f.F > max || math.IsNaN(max) {
+			if f.F > maxVal || math.IsNaN(maxVal) {
-				max = f.F
+				maxVal = f.F
 			}
 		}
-		return max
+		return maxVal
 	}), nil
 }
 
@@ -685,13 +744,13 @@ func funcMinOverTime(vals []parser.Value, args parser.Expressions, enh *EvalNode
 		return enh.Out, nil
 	}
 	return aggrOverTime(vals, enh, func(s Series) float64 {
-		min := s.Floats[0].F
+		minVal := s.Floats[0].F
 		for _, f := range s.Floats {
-			if f.F < min || math.IsNaN(min) {
+			if f.F < minVal || math.IsNaN(minVal) {
-				min = f.F
+				minVal = f.F
 			}
 		}
-		return min
+		return minVal
 	}), nil
 }
 
@@ -837,9 +896,13 @@ func funcPresentOverTime(vals []parser.Value, args parser.Expressions, enh *Eval
 func simpleFunc(vals []parser.Value, enh *EvalNodeHelper, f func(float64) float64) Vector {
 	for _, el := range vals[0].(Vector) {
 		if el.H == nil { // Process only float samples.
+			if !enh.enableDelayedNameRemoval {
+				el.Metric = el.Metric.DropMetricName()
+			}
 			enh.Out = append(enh.Out, Sample{
-				Metric: el.Metric.DropMetricName(),
+				Metric:   el.Metric,
 				F:        f(el.F),
+				DropName: true,
 			})
 		}
 	}
@@ -983,9 +1046,13 @@ func funcSgn(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper)
 func funcTimestamp(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelper) (Vector, annotations.Annotations) {
 	vec := vals[0].(Vector)
 	for _, el := range vec {
+		if !enh.enableDelayedNameRemoval {
+			el.Metric = el.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: el.Metric.DropMetricName(),
+			Metric:   el.Metric,
 			F:        float64(el.T) / 1000,
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -1092,9 +1159,13 @@ func funcHistogramCount(vals []parser.Value, args parser.Expressions, enh *EvalN
 		if sample.H == nil {
 			continue
 		}
+		if !enh.enableDelayedNameRemoval {
+			sample.Metric = sample.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: sample.Metric.DropMetricName(),
+			Metric:   sample.Metric,
 			F:        sample.H.Count,
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -1109,9 +1180,13 @@ func funcHistogramSum(vals []parser.Value, args parser.Expressions, enh *EvalNod
 		if sample.H == nil {
 			continue
 		}
+		if !enh.enableDelayedNameRemoval {
+			sample.Metric = sample.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: sample.Metric.DropMetricName(),
+			Metric:   sample.Metric,
 			F:        sample.H.Sum,
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -1126,9 +1201,13 @@ func funcHistogramAvg(vals []parser.Value, args parser.Expressions, enh *EvalNod
 		if sample.H == nil {
 			continue
 		}
+		if !enh.enableDelayedNameRemoval {
+			sample.Metric = sample.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: sample.Metric.DropMetricName(),
+			Metric:   sample.Metric,
 			F:        sample.H.Sum / sample.H.Count,
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -1165,9 +1244,13 @@ func funcHistogramStdDev(vals []parser.Value, args parser.Expressions, enh *Eval
 		}
 		variance += cVariance
 		variance /= sample.H.Count
+		if !enh.enableDelayedNameRemoval {
+			sample.Metric = sample.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: sample.Metric.DropMetricName(),
+			Metric:   sample.Metric,
 			F:        math.Sqrt(variance),
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -1204,9 +1287,13 @@ func funcHistogramStdVar(vals []parser.Value, args parser.Expressions, enh *Eval
 		}
 		variance += cVariance
 		variance /= sample.H.Count
+		if !enh.enableDelayedNameRemoval {
+			sample.Metric = sample.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: sample.Metric.DropMetricName(),
+			Metric:   sample.Metric,
 			F:        variance,
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -1223,9 +1310,13 @@ func funcHistogramFraction(vals []parser.Value, args parser.Expressions, enh *Ev
 		if sample.H == nil {
 			continue
 		}
+		if !enh.enableDelayedNameRemoval {
+			sample.Metric = sample.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: sample.Metric.DropMetricName(),
+			Metric:   sample.Metric,
 			F:        histogramFraction(lower, upper, sample.H),
+			DropName: true,
 		})
 	}
 	return enh.Out, nil
@@ -1293,9 +1384,13 @@ func funcHistogramQuantile(vals []parser.Value, args parser.Expressions, enh *Ev
 			continue
 		}
 
+		if !enh.enableDelayedNameRemoval {
+			sample.Metric = sample.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: sample.Metric.DropMetricName(),
+			Metric:   sample.Metric,
 			F:        histogramQuantile(q, sample.H),
+			DropName: true,
 		})
 	}
 
@@ -1369,7 +1464,7 @@ func funcChanges(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelp
 }
 
 // label_replace function operates only on series; does not look at timestamps or values.
-func (ev *evaluator) evalLabelReplace(args parser.Expressions) (parser.Value, annotations.Annotations) {
+func (ev *evaluator) evalLabelReplace(ctx context.Context, args parser.Expressions) (parser.Value, annotations.Annotations) {
 	var (
 		dst      = stringFromArg(args[1])
 		repl     = stringFromArg(args[2])
@@ -1385,7 +1480,7 @@ func (ev *evaluator) evalLabelReplace(args parser.Expressions) (parser.Value, an
 		panic(fmt.Errorf("invalid destination label name in label_replace(): %s", dst))
 	}
 
-	val, ws := ev.eval(args[0])
+	val, ws := ev.eval(ctx, args[0])
 	matrix := val.(Matrix)
 	lb := labels.NewBuilder(labels.EmptyLabels())
 
@@ -1397,6 +1492,11 @@ func (ev *evaluator) evalLabelReplace(args parser.Expressions) (parser.Value, an
 			lb.Reset(el.Metric)
 			lb.Set(dst, string(res))
 			matrix[i].Metric = lb.Labels()
+			if dst == model.MetricNameLabel {
+				matrix[i].DropName = false
+			} else {
+				matrix[i].DropName = el.DropName
+			}
 		}
 	}
 	if matrix.ContainsSameLabelset() {
@@ -1421,7 +1521,7 @@ func funcVector(vals []parser.Value, args parser.Expressions, enh *EvalNodeHelpe
 }
 
 // label_join function operates only on series; does not look at timestamps or values.
-func (ev *evaluator) evalLabelJoin(args parser.Expressions) (parser.Value, annotations.Annotations) {
+func (ev *evaluator) evalLabelJoin(ctx context.Context, args parser.Expressions) (parser.Value, annotations.Annotations) {
 	var (
 		dst       = stringFromArg(args[1])
 		sep       = stringFromArg(args[2])
@@ -1438,7 +1538,7 @@ func (ev *evaluator) evalLabelJoin(args parser.Expressions) (parser.Value, annot
 		panic(fmt.Errorf("invalid destination label name in label_join(): %s", dst))
 	}
 
-	val, ws := ev.eval(args[0])
+	val, ws := ev.eval(ctx, args[0])
 	matrix := val.(Matrix)
 	srcVals := make([]string, len(srcLabels))
 	lb := labels.NewBuilder(labels.EmptyLabels())
@@ -1451,6 +1551,12 @@ func (ev *evaluator) evalLabelJoin(args parser.Expressions) (parser.Value, annot
 		lb.Reset(el.Metric)
 		lb.Set(dst, strval)
 		matrix[i].Metric = lb.Labels()
+
+		if dst == model.MetricNameLabel {
+			matrix[i].DropName = false
+		} else {
+			matrix[i].DropName = el.DropName
+		}
 	}
 
 	return matrix, ws
@@ -1473,9 +1579,13 @@ func dateWrapper(vals []parser.Value, enh *EvalNodeHelper, f func(time.Time) flo
 
 	for _, el := range vals[0].(Vector) {
 		t := time.Unix(int64(el.F), 0).UTC()
+		if !enh.enableDelayedNameRemoval {
+			el.Metric = el.Metric.DropMetricName()
+		}
 		enh.Out = append(enh.Out, Sample{
-			Metric: el.Metric.DropMetricName(),
+			Metric:   el.Metric,
 			F:        f(t),
+			DropName: true,
 		})
 	}
 	return enh.Out

promql/functions_test.go

@@ -24,6 +24,7 @@ import (
 	"github.com/prometheus/prometheus/model/timestamp"
 	"github.com/prometheus/prometheus/promql"
 	"github.com/prometheus/prometheus/promql/parser"
+	"github.com/prometheus/prometheus/promql/promqltest"
 	"github.com/prometheus/prometheus/util/teststorage"
 )
 
@@ -39,7 +40,7 @@ func TestDeriv(t *testing.T) {
 		MaxSamples: 10000,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 
 	a := storage.Appender(context.Background())
 

promql/fuzz.go

@@ -68,6 +68,10 @@ func fuzzParseMetricWithContentType(in []byte, contentType string) int {
 		panic(warning)
 	}
 
+	if contentType == "application/openmetrics-text" {
+		p = textparse.NewOpenMetricsParser(in, symbolTable)
+	}
+
 	var err error
 	for {
 		_, err = p.Next()

promql/parser/ast.go

@@ -352,8 +352,7 @@ func (f inspector) Visit(node Node, path []Node) (Visitor, error) {
 // f(node, path); node must not be nil. If f returns a nil error, Inspect invokes f
 // for all the non-nil children of node, recursively.
 func Inspect(node Node, f inspector) {
-	//nolint: errcheck
+	Walk(f, node, nil) //nolint:errcheck
-	Walk(f, node, nil)
 }
 
 // Children returns a list of all child nodes of a syntax tree node.
@@ -419,7 +418,7 @@ func mergeRanges(first, last Node) posrange.PositionRange {
 	}
 }
 
-// Item implements the Node interface.
+// PositionRange implements the Node interface.
 // This makes it possible to call mergeRanges on them.
 func (i *Item) PositionRange() posrange.PositionRange {
 	return posrange.PositionRange{

promql/parser/generated_parser.y

@@ -23,6 +23,8 @@ import (
         "github.com/prometheus/prometheus/model/value"
         "github.com/prometheus/prometheus/model/histogram"
         "github.com/prometheus/prometheus/promql/parser/posrange"
+
+        "github.com/prometheus/common/model"
 )
 
 %}
@@ -360,11 +362,19 @@ grouping_label_list:
 
 grouping_label  : maybe_label
                         {
-                        if !isLabel($1.Val) {
+                        if !model.LabelName($1.Val).IsValid() {
                                 yylex.(*parser).unexpected("grouping opts", "label")
                         }
                         $$ = $1
                         }
+                | STRING {
+                        if !model.LabelName(yylex.(*parser).unquoteString($1.Val)).IsValid() {
+                                yylex.(*parser).unexpected("grouping opts", "label")
+                        }
+                        $$ = $1
+                        $$.Pos++
+                        $$.Val = yylex.(*parser).unquoteString($$.Val)
+                        }
                 | error
                         { yylex.(*parser).unexpected("grouping opts", "label"); $$ = Item{} }
                 ;

promql/parser/lex.go

@@ -617,6 +617,16 @@ func lexBuckets(l *Lexer) stateFn {
 		l.bracketOpen = false
 		l.emit(RIGHT_BRACKET)
 		return lexHistogram
+	case isAlpha(r):
+		// Current word is Inf or NaN.
+		word := l.input[l.start:l.pos]
+		if desc, ok := key[strings.ToLower(word)]; ok {
+			if desc == NUMBER {
+				l.emit(desc)
+				return lexStatements
+			}
+		}
+		return lexBuckets
 	default:
 		return l.errorf("invalid character in buckets description: %q", r)
 	}
@@ -727,23 +737,23 @@ func lexValueSequence(l *Lexer) stateFn {
 // was only modified to integrate with our lexer.
 func lexEscape(l *Lexer) stateFn {
 	var n int
-	var base, max uint32
+	var base, maxVal uint32
 
 	ch := l.next()
 	switch ch {
 	case 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', l.stringOpen:
 		return lexString
 	case '0', '1', '2', '3', '4', '5', '6', '7':
-		n, base, max = 3, 8, 255
+		n, base, maxVal = 3, 8, 255
 	case 'x':
 		ch = l.next()
-		n, base, max = 2, 16, 255
+		n, base, maxVal = 2, 16, 255
 	case 'u':
 		ch = l.next()
-		n, base, max = 4, 16, unicode.MaxRune
+		n, base, maxVal = 4, 16, unicode.MaxRune
 	case 'U':
 		ch = l.next()
-		n, base, max = 8, 16, unicode.MaxRune
+		n, base, maxVal = 8, 16, unicode.MaxRune
 	case eof:
 		l.errorf("escape sequence not terminated")
 		return lexString
@@ -772,7 +782,7 @@ func lexEscape(l *Lexer) stateFn {
 		}
 	}
 
-	if x > max || 0xD800 <= x && x < 0xE000 {
+	if x > maxVal || 0xD800 <= x && x < 0xE000 {
 		l.errorf("escape sequence is an invalid Unicode code point")
 	}
 	return lexString
@@ -1059,16 +1069,3 @@ func isDigit(r rune) bool {
 func isAlpha(r rune) bool {
 	return r == '_' || ('a' <= r && r <= 'z') || ('A' <= r && r <= 'Z')
 }
-
-// isLabel reports whether the string can be used as label.
-func isLabel(s string) bool {
-	if len(s) == 0 || !isAlpha(rune(s[0])) {
-		return false
-	}
-	for _, c := range s[1:] {
-		if !isAlphaNumeric(c) {
-			return false
-		}
-	}
-	return true
-}

promql/parser/lex_test.go

@@ -639,6 +639,29 @@ var tests = []struct {
 				},
 				seriesDesc: true,
 			},
+			{
+				input: `{} {{buckets: [Inf NaN] schema:1}}`,
+				expected: []Item{
+					{LEFT_BRACE, 0, `{`},
+					{RIGHT_BRACE, 1, `}`},
+					{SPACE, 2, ` `},
+					{OPEN_HIST, 3, `{{`},
+					{BUCKETS_DESC, 5, `buckets`},
+					{COLON, 12, `:`},
+					{SPACE, 13, ` `},
+					{LEFT_BRACKET, 14, `[`},
+					{NUMBER, 15, `Inf`},
+					{SPACE, 18, ` `},
+					{NUMBER, 19, `NaN`},
+					{RIGHT_BRACKET, 22, `]`},
+					{SPACE, 23, ` `},
+					{SCHEMA_DESC, 24, `schema`},
+					{COLON, 30, `:`},
+					{NUMBER, 31, `1`},
+					{CLOSE_HIST, 32, `}}`},
+				},
+				seriesDesc: true,
+			},
 			{ // Series with sum as -Inf and count as NaN.
 				input: `{} {{buckets: [5 10 7] sum:Inf count:NaN}}`,
 				expected: []Item{

promql/parser/parse_test.go

@@ -2397,6 +2397,51 @@ var testExpr = []struct {
 			},
 		},
 	},
+	{
+		input: `sum by ("foo")({"some.metric"})`,
+		expected: &AggregateExpr{
+			Op: SUM,
+			Expr: &VectorSelector{
+				LabelMatchers: []*labels.Matcher{
+					MustLabelMatcher(labels.MatchEqual, model.MetricNameLabel, "some.metric"),
+				},
+				PosRange: posrange.PositionRange{
+					Start: 15,
+					End:   30,
+				},
+			},
+			Grouping: []string{"foo"},
+			PosRange: posrange.PositionRange{
+				Start: 0,
+				End:   31,
+			},
+		},
+	},
+	{
+		input:  `sum by ("foo)(some_metric{})`,
+		fail:   true,
+		errMsg: "unterminated quoted string",
+	},
+	{
+		input: `sum by ("foo", bar, 'baz')({"some.metric"})`,
+		expected: &AggregateExpr{
+			Op: SUM,
+			Expr: &VectorSelector{
+				LabelMatchers: []*labels.Matcher{
+					MustLabelMatcher(labels.MatchEqual, model.MetricNameLabel, "some.metric"),
+				},
+				PosRange: posrange.PositionRange{
+					Start: 27,
+					End:   42,
+				},
+			},
+			Grouping: []string{"foo", "bar", "baz"},
+			PosRange: posrange.PositionRange{
+				Start: 0,
+				End:   43,
+			},
+		},
+	},
 	{
 		input: "avg by (foo)(some_metric)",
 		expected: &AggregateExpr{
@@ -3844,6 +3889,7 @@ func readable(s string) string {
 }
 
 func TestParseExpressions(t *testing.T) {
+	model.NameValidationScheme = model.UTF8Validation
 	for _, test := range testExpr {
 		t.Run(readable(test.input), func(t *testing.T) {
 			expr, err := ParseExpr(test.input)

promql/parser/printer.go

@@ -72,27 +72,48 @@ func (node *AggregateExpr) String() string {
 	return aggrString
 }
 
+func (node *AggregateExpr) ShortString() string {
+	aggrString := node.getAggOpStr()
+	return aggrString
+}
+
 func (node *AggregateExpr) getAggOpStr() string {
 	aggrString := node.Op.String()
 
 	switch {
 	case node.Without:
-		aggrString += fmt.Sprintf(" without (%s) ", strings.Join(node.Grouping, ", "))
+		aggrString += fmt.Sprintf(" without (%s) ", joinLabels(node.Grouping))
 	case len(node.Grouping) > 0:
-		aggrString += fmt.Sprintf(" by (%s) ", strings.Join(node.Grouping, ", "))
+		aggrString += fmt.Sprintf(" by (%s) ", joinLabels(node.Grouping))
 	}
 
 	return aggrString
 }
 
-func (node *BinaryExpr) String() string {
+func joinLabels(ss []string) string {
-	returnBool := ""
+	for i, s := range ss {
-	if node.ReturnBool {
+		// If the label is already quoted, don't quote it again.
-		returnBool = " bool"
+		if s[0] != '"' && s[0] != '\'' && s[0] != '`' && !model.IsValidLegacyMetricName(string(model.LabelValue(s))) {
+			ss[i] = fmt.Sprintf("\"%s\"", s)
 		}
+	}
+	return strings.Join(ss, ", ")
+}
 
+func (node *BinaryExpr) returnBool() string {
+	if node.ReturnBool {
+		return " bool"
+	}
+	return ""
+}
+
+func (node *BinaryExpr) String() string {
 	matching := node.getMatchingStr()
-	return fmt.Sprintf("%s %s%s%s %s", node.LHS, node.Op, returnBool, matching, node.RHS)
+	return fmt.Sprintf("%s %s%s%s %s", node.LHS, node.Op, node.returnBool(), matching, node.RHS)
+}
+
+func (node *BinaryExpr) ShortString() string {
+	return fmt.Sprintf("%s%s%s", node.Op, node.returnBool(), node.getMatchingStr())
 }
 
 func (node *BinaryExpr) getMatchingStr() string {
@@ -120,9 +141,13 @@ func (node *Call) String() string {
 	return fmt.Sprintf("%s(%s)", node.Func.Name, node.Args)
 }
 
-func (node *MatrixSelector) String() string {
+func (node *Call) ShortString() string {
+	return node.Func.Name
+}
+
+func (node *MatrixSelector) atOffset() (string, string) {
 	// Copy the Vector selector before changing the offset
-	vecSelector := *node.VectorSelector.(*VectorSelector)
+	vecSelector := node.VectorSelector.(*VectorSelector)
 	offset := ""
 	switch {
 	case vecSelector.OriginalOffset > time.Duration(0):
@@ -139,7 +164,13 @@ func (node *MatrixSelector) String() string {
 	case vecSelector.StartOrEnd == END:
 		at = " @ end()"
 	}
+	return at, offset
+}
 
+func (node *MatrixSelector) String() string {
+	at, offset := node.atOffset()
+	// Copy the Vector selector before changing the offset
+	vecSelector := *node.VectorSelector.(*VectorSelector)
 	// Do not print the @ and offset twice.
 	offsetVal, atVal, preproc := vecSelector.OriginalOffset, vecSelector.Timestamp, vecSelector.StartOrEnd
 	vecSelector.OriginalOffset = 0
@@ -153,10 +184,19 @@ func (node *MatrixSelector) String() string {
 	return str
 }
 
+func (node *MatrixSelector) ShortString() string {
+	at, offset := node.atOffset()
+	return fmt.Sprintf("[%s]%s%s", model.Duration(node.Range), at, offset)
+}
+
 func (node *SubqueryExpr) String() string {
 	return fmt.Sprintf("%s%s", node.Expr.String(), node.getSubqueryTimeSuffix())
 }
 
+func (node *SubqueryExpr) ShortString() string {
+	return node.getSubqueryTimeSuffix()
+}
+
 // getSubqueryTimeSuffix returns the '[<range>:<step>] @ <timestamp> offset <offset>' suffix of the subquery.
 func (node *SubqueryExpr) getSubqueryTimeSuffix() string {
 	step := ""
@@ -198,6 +238,10 @@ func (node *UnaryExpr) String() string {
 	return fmt.Sprintf("%s%s", node.Op, node.Expr)
 }
 
+func (node *UnaryExpr) ShortString() string {
+	return node.Op.String()
+}
+
 func (node *VectorSelector) String() string {
 	var labelStrings []string
 	if len(node.LabelMatchers) > 1 {

promql/parser/printer_test.go

@@ -16,6 +16,7 @@ package parser
 import (
 	"testing"
 
+	"github.com/prometheus/common/model"
 	"github.com/stretchr/testify/require"
 
 	"github.com/prometheus/prometheus/model/labels"
@@ -44,6 +45,14 @@ func TestExprString(t *testing.T) {
 			in:  `sum without(instance) (task:errors:rate10s{job="s"})`,
 			out: `sum without (instance) (task:errors:rate10s{job="s"})`,
 		},
+		{
+			in:  `sum by("foo.bar") (task:errors:rate10s{job="s"})`,
+			out: `sum by ("foo.bar") (task:errors:rate10s{job="s"})`,
+		},
+		{
+			in:  `sum without("foo.bar") (task:errors:rate10s{job="s"})`,
+			out: `sum without ("foo.bar") (task:errors:rate10s{job="s"})`,
+		},
 		{
 			in: `topk(5, task:errors:rate10s{job="s"})`,
 		},
@@ -157,6 +166,8 @@ func TestExprString(t *testing.T) {
 		},
 	}
 
+	model.NameValidationScheme = model.UTF8Validation
+
 	for _, test := range inputs {
 		expr, err := ParseExpr(test.in)
 		require.NoError(t, err)

promql/promql_test.go

@@ -28,12 +28,12 @@ import (
 	"github.com/prometheus/prometheus/util/teststorage"
 )
 
-func newTestEngine() *promql.Engine {
+func newTestEngine(t *testing.T) *promql.Engine {
-	return promqltest.NewTestEngine(false, 0, promqltest.DefaultMaxSamplesPerQuery)
+	return promqltest.NewTestEngine(t, false, 0, promqltest.DefaultMaxSamplesPerQuery)
 }
 
 func TestEvaluations(t *testing.T) {
-	promqltest.RunBuiltinTests(t, newTestEngine())
+	promqltest.RunBuiltinTests(t, newTestEngine(t))
 }
 
 // Run a lot of queries at the same time, to check for race conditions.
@@ -48,7 +48,7 @@ func TestConcurrentRangeQueries(t *testing.T) {
 	}
 	// Enable experimental functions testing
 	parser.EnableExperimentalFunctions = true
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 
 	const interval = 10000 // 10s interval.
 	// A day of data plus 10k steps.

promql/promqltest/test.go

@@ -79,8 +79,9 @@ func LoadedStorage(t testutil.T, input string) *teststorage.TestStorage {
 	return test.storage
 }
 
-func NewTestEngine(enablePerStepStats bool, lookbackDelta time.Duration, maxSamples int) *promql.Engine {
+// NewTestEngine creates a promql.Engine with enablePerStepStats, lookbackDelta and maxSamples, and returns it.
-	return promql.NewEngine(promql.EngineOpts{
+func NewTestEngine(tb testing.TB, enablePerStepStats bool, lookbackDelta time.Duration, maxSamples int) *promql.Engine {
+	return NewTestEngineWithOpts(tb, promql.EngineOpts{
 		Logger:                   nil,
 		Reg:                      nil,
 		MaxSamples:               maxSamples,
@@ -90,9 +91,20 @@ func NewTestEngine(enablePerStepStats bool, lookbackDelta time.Duration, maxSamp
 		EnableNegativeOffset:     true,
 		EnablePerStepStats:       enablePerStepStats,
 		LookbackDelta:            lookbackDelta,
+		EnableDelayedNameRemoval: true,
 	})
 }
 
+// NewTestEngineWithOpts creates a promql.Engine with opts and returns it.
+func NewTestEngineWithOpts(tb testing.TB, opts promql.EngineOpts) *promql.Engine {
+	tb.Helper()
+	ng := promql.NewEngine(opts)
+	tb.Cleanup(func() {
+		require.NoError(tb, ng.Close())
+	})
+	return ng
+}
+
 // RunBuiltinTests runs an acceptance test suite against the provided engine.
 func RunBuiltinTests(t TBRun, engine promql.QueryEngine) {
 	t.Cleanup(func() { parser.EnableExperimentalFunctions = false })
@@ -651,6 +663,7 @@ type evalCmd struct {
 	expectedFailRegexp  *regexp.Regexp
 
 	metrics      map[uint64]labels.Labels
+	expectScalar bool
 	expected     map[uint64]entry
 }
 
@@ -695,12 +708,15 @@ func (ev *evalCmd) String() string {
 // expect adds a sequence of values to the set of expected
 // results for the query.
 func (ev *evalCmd) expect(pos int, vals ...parser.SequenceValue) {
+	ev.expectScalar = true
 	ev.expected[0] = entry{pos: pos, vals: vals}
 }
 
 // expectMetric adds a new metric with a sequence of values to the set of expected
 // results for the query.
 func (ev *evalCmd) expectMetric(pos int, m labels.Labels, vals ...parser.SequenceValue) {
+	ev.expectScalar = false
+
 	h := m.Hash()
 	ev.metrics[h] = m
 	ev.expected[h] = entry{pos: pos, vals: vals}
@@ -714,6 +730,10 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 			return fmt.Errorf("expected ordered result, but query returned a matrix")
 		}
 
+		if ev.expectScalar {
+			return fmt.Errorf("expected scalar result, but got matrix %s", val.String())
+		}
+
 		if err := assertMatrixSorted(val); err != nil {
 			return err
 		}
@@ -769,7 +789,7 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 					return fmt.Errorf("expected histogram value at index %v for %s to have timestamp %v, but it had timestamp %v (result has %s)", i, ev.metrics[hash], expected.T, actual.T, formatSeriesResult(s))
 				}
 
-				if !actual.H.Equals(expected.H.Compact(0)) {
+				if !compareNativeHistogram(expected.H.Compact(0), actual.H.Compact(0)) {
 					return fmt.Errorf("expected histogram value at index %v (t=%v) for %s to be %v, but got %v (result has %s)", i, actual.T, ev.metrics[hash], expected.H, actual.H, formatSeriesResult(s))
 				}
 			}
@@ -782,6 +802,10 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 		}
 
 	case promql.Vector:
+		if ev.expectScalar {
+			return fmt.Errorf("expected scalar result, but got vector %s", val.String())
+		}
+
 		seen := map[uint64]bool{}
 		for pos, v := range val {
 			fp := v.Metric.Hash()
@@ -804,7 +828,7 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 			if expH != nil && v.H == nil {
 				return fmt.Errorf("expected histogram %s for %s but got float value %v", HistogramTestExpression(expH), v.Metric, v.F)
 			}
-			if expH != nil && !expH.Compact(0).Equals(v.H) {
+			if expH != nil && !compareNativeHistogram(expH.Compact(0), v.H.Compact(0)) {
 				return fmt.Errorf("expected %v for %s but got %s", HistogramTestExpression(expH), v.Metric, HistogramTestExpression(v.H))
 			}
 			if !almost.Equal(exp0.Value, v.F, defaultEpsilon) {
@@ -820,15 +844,15 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 		}
 
 	case promql.Scalar:
-		if len(ev.expected) != 1 {
+		if !ev.expectScalar {
-			return fmt.Errorf("expected vector result, but got scalar %s", val.String())
+			return fmt.Errorf("expected vector or matrix result, but got %s", val.String())
 		}
 		exp0 := ev.expected[0].vals[0]
 		if exp0.Histogram != nil {
-			return fmt.Errorf("expected Histogram %v but got scalar %s", exp0.Histogram.TestExpression(), val.String())
+			return fmt.Errorf("expected histogram %v but got %s", exp0.Histogram.TestExpression(), val.String())
 		}
 		if !almost.Equal(exp0.Value, val.V, defaultEpsilon) {
-			return fmt.Errorf("expected Scalar %v but got %v", val.V, exp0.Value)
+			return fmt.Errorf("expected scalar %v but got %v", exp0.Value, val.V)
 		}
 
 	default:
@@ -837,6 +861,121 @@ func (ev *evalCmd) compareResult(result parser.Value) error {
 	return nil
 }
 
+// compareNativeHistogram is helper function to compare two native histograms
+// which can tolerate some differ in the field of float type, such as Count, Sum.
+func compareNativeHistogram(exp, cur *histogram.FloatHistogram) bool {
+	if exp == nil || cur == nil {
+		return false
+	}
+
+	if exp.Schema != cur.Schema ||
+		!almost.Equal(exp.Count, cur.Count, defaultEpsilon) ||
+		!almost.Equal(exp.Sum, cur.Sum, defaultEpsilon) {
+		return false
+	}
+
+	if exp.UsesCustomBuckets() {
+		if !histogram.FloatBucketsMatch(exp.CustomValues, cur.CustomValues) {
+			return false
+		}
+	}
+
+	if exp.ZeroThreshold != cur.ZeroThreshold ||
+		!almost.Equal(exp.ZeroCount, cur.ZeroCount, defaultEpsilon) {
+		return false
+	}
+
+	if !spansMatch(exp.NegativeSpans, cur.NegativeSpans) {
+		return false
+	}
+	if !floatBucketsMatch(exp.NegativeBuckets, cur.NegativeBuckets) {
+		return false
+	}
+
+	if !spansMatch(exp.PositiveSpans, cur.PositiveSpans) {
+		return false
+	}
+	if !floatBucketsMatch(exp.PositiveBuckets, cur.PositiveBuckets) {
+		return false
+	}
+
+	return true
+}
+
+func floatBucketsMatch(b1, b2 []float64) bool {
+	if len(b1) != len(b2) {
+		return false
+	}
+	for i, b := range b1 {
+		if !almost.Equal(b, b2[i], defaultEpsilon) {
+			return false
+		}
+	}
+	return true
+}
+
+func spansMatch(s1, s2 []histogram.Span) bool {
+	if len(s1) == 0 && len(s2) == 0 {
+		return true
+	}
+
+	s1idx, s2idx := 0, 0
+	for {
+		if s1idx >= len(s1) {
+			return allEmptySpans(s2[s2idx:])
+		}
+		if s2idx >= len(s2) {
+			return allEmptySpans(s1[s1idx:])
+		}
+
+		currS1, currS2 := s1[s1idx], s2[s2idx]
+		s1idx++
+		s2idx++
+		if currS1.Length == 0 {
+			// This span is zero length, so we add consecutive such spans
+			// until we find a non-zero span.
+			for ; s1idx < len(s1) && s1[s1idx].Length == 0; s1idx++ {
+				currS1.Offset += s1[s1idx].Offset
+			}
+			if s1idx < len(s1) {
+				currS1.Offset += s1[s1idx].Offset
+				currS1.Length = s1[s1idx].Length
+				s1idx++
+			}
+		}
+		if currS2.Length == 0 {
+			// This span is zero length, so we add consecutive such spans
+			// until we find a non-zero span.
+			for ; s2idx < len(s2) && s2[s2idx].Length == 0; s2idx++ {
+				currS2.Offset += s2[s2idx].Offset
+			}
+			if s2idx < len(s2) {
+				currS2.Offset += s2[s2idx].Offset
+				currS2.Length = s2[s2idx].Length
+				s2idx++
+			}
+		}
+
+		if currS1.Length == 0 && currS2.Length == 0 {
+			// The last spans of both set are zero length. Previous spans match.
+			return true
+		}
+
+		if currS1.Offset != currS2.Offset || currS1.Length != currS2.Length {
+			return false
+		}
+	}
+}
+
+func allEmptySpans(s []histogram.Span) bool {
+	for _, ss := range s {
+		if ss.Length > 0 {
+			return false
+		}
+	}
+	return true
+}
+
 func (ev *evalCmd) checkExpectedFailure(actual error) error {
 	if ev.expectedFailMessage != "" {
 		if ev.expectedFailMessage != actual.Error() {
@@ -1003,13 +1142,6 @@ func (t *test) execRangeEval(cmd *evalCmd, engine promql.QueryEngine) error {
 		return fmt.Errorf("error creating range query for %q (line %d): %w", cmd.expr, cmd.line, err)
 	}
 	res := q.Exec(t.context)
-	countWarnings, _ := res.Warnings.CountWarningsAndInfo()
-	if !cmd.warn && countWarnings > 0 {
-		return fmt.Errorf("unexpected warnings evaluating query %q (line %d): %v", cmd.expr, cmd.line, res.Warnings)
-	}
-	if cmd.warn && countWarnings == 0 {
-		return fmt.Errorf("expected warnings evaluating query %q (line %d) but got none", cmd.expr, cmd.line)
-	}
 	if res.Err != nil {
 		if cmd.fail {
 			return cmd.checkExpectedFailure(res.Err)
@@ -1020,6 +1152,13 @@ func (t *test) execRangeEval(cmd *evalCmd, engine promql.QueryEngine) error {
 	if res.Err == nil && cmd.fail {
 		return fmt.Errorf("expected error evaluating query %q (line %d) but got none", cmd.expr, cmd.line)
 	}
+	countWarnings, _ := res.Warnings.CountWarningsAndInfo()
+	if !cmd.warn && countWarnings > 0 {
+		return fmt.Errorf("unexpected warnings evaluating query %q (line %d): %v", cmd.expr, cmd.line, res.Warnings)
+	}
+	if cmd.warn && countWarnings == 0 {
+		return fmt.Errorf("expected warnings evaluating query %q (line %d) but got none", cmd.expr, cmd.line)
+	}
 	defer q.Close()
 
 	if err := cmd.compareResult(res.Value); err != nil {
@@ -1050,13 +1189,6 @@ func (t *test) runInstantQuery(iq atModifierTestCase, cmd *evalCmd, engine promq
 	}
 	defer q.Close()
 	res := q.Exec(t.context)
-	countWarnings, _ := res.Warnings.CountWarningsAndInfo()
-	if !cmd.warn && countWarnings > 0 {
-		return fmt.Errorf("unexpected warnings evaluating query %q (line %d): %v", iq.expr, cmd.line, res.Warnings)
-	}
-	if cmd.warn && countWarnings == 0 {
-		return fmt.Errorf("expected warnings evaluating query %q (line %d) but got none", iq.expr, cmd.line)
-	}
 	if res.Err != nil {
 		if cmd.fail {
 			if err := cmd.checkExpectedFailure(res.Err); err != nil {
@@ -1070,6 +1202,13 @@ func (t *test) runInstantQuery(iq atModifierTestCase, cmd *evalCmd, engine promq
 	if res.Err == nil && cmd.fail {
 		return fmt.Errorf("expected error evaluating query %q (line %d) but got none", iq.expr, cmd.line)
 	}
+	countWarnings, _ := res.Warnings.CountWarningsAndInfo()
+	if !cmd.warn && countWarnings > 0 {
+		return fmt.Errorf("unexpected warnings evaluating query %q (line %d): %v", iq.expr, cmd.line, res.Warnings)
+	}
+	if cmd.warn && countWarnings == 0 {
+		return fmt.Errorf("expected warnings evaluating query %q (line %d) but got none", iq.expr, cmd.line)
+	}
 	err = cmd.compareResult(res.Value)
 	if err != nil {
 		return fmt.Errorf("error in %s %s (line %d): %w", cmd, iq.expr, cmd.line, err)
@@ -1247,6 +1386,7 @@ func (ll *LazyLoader) clear() error {
 		NoStepSubqueryIntervalFn: func(int64) int64 { return durationMilliseconds(ll.SubqueryInterval) },
 		EnableAtModifier:         ll.opts.EnableAtModifier,
 		EnableNegativeOffset:     ll.opts.EnableNegativeOffset,
+		EnableDelayedNameRemoval: true,
 	}
 
 	ll.queryEngine = promql.NewEngine(opts)
@@ -1307,7 +1447,11 @@ func (ll *LazyLoader) Storage() storage.Storage {
 // Close closes resources associated with the LazyLoader.
 func (ll *LazyLoader) Close() error {
 	ll.cancelCtx()
-	return ll.storage.Close()
+	err := ll.queryEngine.Close()
+	if sErr := ll.storage.Close(); sErr != nil {
+		return errors.Join(sErr, err)
+	}
+	return err
 }
 
 func makeInt64Pointer(val int64) *int64 {

promql/promqltest/test_test.go

@@ -554,11 +554,48 @@ eval range from 0 to 5m step 5m testmetric
 `,
 			expectedError: `error in eval testmetric (line 5): expected float value at index 0 for {__name__="testmetric"} to have timestamp 300000, but it had timestamp 0 (result has 1 float point [3 @[0]] and 1 histogram point [{count:0, sum:0} @[300000]])`,
 		},
+		"instant query with expected scalar result": {
+			input: `
+				eval instant at 1m 3
+					3
+			`,
+		},
+		"instant query with unexpected scalar result": {
+			input: `
+				eval instant at 1m 3
+					2
+			`,
+			expectedError: `error in eval 3 (line 2): expected scalar 2 but got 3`,
+		},
+		"instant query that returns a scalar but expects a vector": {
+			input: `
+				eval instant at 1m 3
+					{} 3
+			`,
+			expectedError: `error in eval 3 (line 2): expected vector or matrix result, but got scalar: 3 @[60000]`,
+		},
+		"instant query that returns a vector but expects a scalar": {
+			input: `
+				eval instant at 1m vector(3)
+					3
+			`,
+			expectedError: `error in eval vector(3) (line 2): expected scalar result, but got vector {} => 3 @[60000]`,
+		},
+		"range query that returns a matrix but expects a scalar": {
+			input: `
+				eval range from 0 to 1m step 30s vector(3)
+					3
+			`,
+			expectedError: `error in eval vector(3) (line 2): expected scalar result, but got matrix {} =>
+3 @[0]
+3 @[30000]
+3 @[60000]`,
+		},
 	}
 
 	for name, testCase := range testCases {
 		t.Run(name, func(t *testing.T) {
-			err := runTest(t, testCase.input, NewTestEngine(false, 0, DefaultMaxSamplesPerQuery))
+			err := runTest(t, testCase.input, NewTestEngine(t, false, 0, DefaultMaxSamplesPerQuery))
 
 			if testCase.expectedError == "" {
 				require.NoError(t, err)

promql/promqltest/testdata/aggregators.test

@@ -503,7 +503,7 @@ eval instant at 1m avg(data{test="-big"})
 eval instant at 1m avg(data{test="bigzero"})
 	{} 0
 
-# Test summing extreme values.
+# Test summing and averaging extreme values.
 clear
 
 load 10s
@@ -529,21 +529,39 @@ load 10s
 eval instant at 1m sum(data{test="ten"})
 	{} 10
 
+eval instant at 1m avg(data{test="ten"})
+	{} 2.5
+
 eval instant at 1m sum by (group) (data{test="pos_inf"})
 	{group="1"} Inf
 	{group="2"} Inf
 
+eval instant at 1m avg by (group) (data{test="pos_inf"})
+	{group="1"} Inf
+	{group="2"} Inf
+
 eval instant at 1m sum by (group) (data{test="neg_inf"})
 	{group="1"} -Inf
 	{group="2"} -Inf
 
+eval instant at 1m avg by (group) (data{test="neg_inf"})
+	{group="1"} -Inf
+	{group="2"} -Inf
+
 eval instant at 1m sum(data{test="inf_inf"})
 	{} NaN
 
+eval instant at 1m avg(data{test="inf_inf"})
+	{} NaN
+
 eval instant at 1m sum by (group) (data{test="nan"})
 	{group="1"} NaN
 	{group="2"} NaN
 
+eval instant at 1m avg by (group) (data{test="nan"})
+	{group="1"} NaN
+	{group="2"} NaN
+
 clear
 
 # Test that aggregations are deterministic.

promql/promqltest/testdata/functions.test

@@ -523,16 +523,16 @@ load 5m
 	node_uname_info{job="node_exporter", instance="4m1000", release="1.111.3"} 0+10x10
 
 eval_ordered instant at 50m sort_by_label(http_requests, "instance")
-	http_requests{group="production", instance="0", job="api-server"} 100
 	http_requests{group="canary", instance="0", job="api-server"} 300
-	http_requests{group="production", instance="0", job="app-server"} 500
 	http_requests{group="canary", instance="0", job="app-server"} 700
-	http_requests{group="production", instance="1", job="api-server"} 200
+	http_requests{group="production", instance="0", job="api-server"} 100
+	http_requests{group="production", instance="0", job="app-server"} 500
 	http_requests{group="canary", instance="1", job="api-server"} 400
-	http_requests{group="production", instance="1", job="app-server"} 600
 	http_requests{group="canary", instance="1", job="app-server"} 800
-	http_requests{group="production", instance="2", job="api-server"} 100
+	http_requests{group="production", instance="1", job="api-server"} 200
+	http_requests{group="production", instance="1", job="app-server"} 600
 	http_requests{group="canary", instance="2", job="api-server"} NaN
+	http_requests{group="production", instance="2", job="api-server"} 100
 
 eval_ordered instant at 50m sort_by_label(http_requests, "instance", "group")
 	http_requests{group="canary", instance="0", job="api-server"} 300
@@ -585,14 +585,14 @@ eval_ordered instant at 50m sort_by_label(http_requests, "job", "instance", "gro
 eval_ordered instant at 50m sort_by_label_desc(http_requests, "instance")
 	http_requests{group="production", instance="2", job="api-server"} 100
 	http_requests{group="canary", instance="2", job="api-server"} NaN
-	http_requests{group="canary", instance="1", job="app-server"} 800
 	http_requests{group="production", instance="1", job="app-server"} 600
-	http_requests{group="canary", instance="1", job="api-server"} 400
 	http_requests{group="production", instance="1", job="api-server"} 200
-	http_requests{group="canary", instance="0", job="app-server"} 700
+	http_requests{group="canary", instance="1", job="app-server"} 800
+	http_requests{group="canary", instance="1", job="api-server"} 400
 	http_requests{group="production", instance="0", job="app-server"} 500
-	http_requests{group="canary", instance="0", job="api-server"} 300
 	http_requests{group="production", instance="0", job="api-server"} 100
+	http_requests{group="canary", instance="0", job="app-server"} 700
+	http_requests{group="canary", instance="0", job="api-server"} 300
 
 eval_ordered instant at 50m sort_by_label_desc(http_requests, "instance", "group")
 	http_requests{group="production", instance="2", job="api-server"} 100
@@ -748,7 +748,6 @@ eval instant at 1m avg_over_time(metric6c[1m])
 eval instant at 1m sum_over_time(metric6c[1m])/count_over_time(metric6c[1m])
   {} NaN
 
-
 eval instant at 1m avg_over_time(metric7[1m])
   {} NaN
 
@@ -783,6 +782,9 @@ load 10s
 eval instant at 1m sum_over_time(metric[1m])
   {} 2
 
+eval instant at 1m avg_over_time(metric[1m])
+  {} 0.5
+
 # Tests for stddev_over_time and stdvar_over_time.
 clear
 load 10s

promql/promqltest/testdata/histograms.test

@@ -482,3 +482,29 @@ load_with_nhcb 5m
 eval_fail instant at 50m histogram_quantile(0.99, {__name__=~"request_duration_seconds\\d*_bucket"})
 
 eval_fail instant at 50m histogram_quantile(0.99, {__name__=~"request_duration_seconds\\d*"})
+
+# Histogram with constant buckets.
+load_with_nhcb 1m
+    const_histogram_bucket{le="0.0"} 1 1 1 1 1
+    const_histogram_bucket{le="1.0"} 1 1 1 1 1
+    const_histogram_bucket{le="2.0"} 1 1 1 1 1
+    const_histogram_bucket{le="+Inf"} 1 1 1 1 1
+
+# There is no change to the bucket count over time, thus rate is 0 in each bucket.
+eval instant at 5m rate(const_histogram_bucket[5m])
+    {le="0.0"} 0
+    {le="1.0"} 0
+    {le="2.0"} 0
+    {le="+Inf"} 0
+
+# Native histograms do not represent empty buckets, so here the zeros are implicit.
+eval instant at 5m rate(const_histogram[5m])
+    {} {{schema:-53 sum:0 count:0 custom_values:[0.0 1.0 2.0]}}
+
+# Zero buckets mean no observations, so there is no value that observations fall below,
+# which means that any quantile is a NaN.
+eval instant at 5m histogram_quantile(1.0, sum by (le) (rate(const_histogram_bucket[5m])))
+    {} NaN
+
+eval instant at 5m histogram_quantile(1.0, sum(rate(const_histogram[5m])))
+    {} NaN

promql/promqltest/testdata/name_label_dropping.test

@@ -0,0 +1,84 @@
+# Test for __name__ label drop.
+load 5m
+	metric{env="1"}	0 60 120
+	another_metric{env="1"}	60 120 180
+
+# Does not drop __name__ for vector selector
+eval instant at 15m metric{env="1"}
+	metric{env="1"} 120
+
+# Drops __name__ for unary operators
+eval instant at 15m -metric
+	{env="1"} -120
+
+# Drops __name__ for binary operators
+eval instant at 15m metric + another_metric
+	{env="1"} 300
+
+# Does not drop __name__ for binary comparison operators
+eval instant at 15m metric <= another_metric
+	metric{env="1"} 120
+
+# Drops __name__ for binary comparison operators with "bool" modifier
+eval instant at 15m metric <= bool another_metric
+	{env="1"} 1
+
+# Drops __name__ for vector-scalar operations
+eval instant at 15m metric * 2
+	{env="1"} 240
+
+# Drops __name__ for instant-vector functions
+eval instant at 15m clamp(metric, 0, 100)
+	{env="1"} 100
+
+# Drops __name__ for range-vector functions
+eval instant at 15m rate(metric{env="1"}[10m])
+	{env="1"} 0.2
+
+# Does not drop __name__ for last_over_time function
+eval instant at 15m last_over_time(metric{env="1"}[10m])
+	metric{env="1"} 120
+
+# Drops name for other _over_time functions
+eval instant at 15m max_over_time(metric{env="1"}[10m])
+	{env="1"} 120
+
+# Allows relabeling (to-be-dropped) __name__  via label_replace
+eval instant at 15m label_replace(rate({env="1"}[10m]), "my_name", "rate_$1", "__name__", "(.+)")
+	{my_name="rate_metric", env="1"} 0.2
+	{my_name="rate_another_metric", env="1"} 0.2
+
+# Allows preserving __name__ via label_replace
+eval instant at 15m label_replace(rate({env="1"}[10m]), "__name__", "rate_$1", "__name__", "(.+)")
+	rate_metric{env="1"} 0.2
+	rate_another_metric{env="1"} 0.2
+
+# Allows relabeling (to-be-dropped) __name__  via label_join
+eval instant at 15m label_join(rate({env="1"}[10m]), "my_name", "_", "__name__")
+	{my_name="metric", env="1"} 0.2
+	{my_name="another_metric", env="1"} 0.2
+
+# Allows preserving __name__ via label_join
+eval instant at 15m label_join(rate({env="1"}[10m]), "__name__", "_", "__name__", "env")
+	metric_1{env="1"} 0.2
+	another_metric_1{env="1"} 0.2
+
+# Does not drop metric names fro aggregation operators
+eval instant at 15m sum by (__name__, env) (metric{env="1"})
+	metric{env="1"} 120
+
+# Aggregation operators by __name__ lead to duplicate labelset errors (aggregation is partitioned by not yet removed __name__ label)
+# This is an accidental side effect of delayed __name__ label dropping
+eval_fail instant at 15m sum by (__name__) (rate({env="1"}[10m]))
+
+# Aggregation operators aggregate metrics with same labelset and to-be-dropped names
+# This is an accidental side effect of delayed __name__ label dropping
+eval instant at 15m sum(rate({env="1"}[10m])) by (env)
+	{env="1"} 0.4
+
+# Aggregationk operators propagate __name__ label dropping information
+eval instant at 15m topk(10, sum by (__name__, env) (metric{env="1"}))
+	metric{env="1"} 120
+
+eval instant at 15m topk(10, sum by (__name__, env) (rate(metric{env="1"}[10m])))
+	{env="1"} 0.2

promql/promqltest/testdata/native_histograms.test

@@ -718,6 +718,52 @@ eval instant at 10m histogram_fraction(-Inf, +Inf, histogram_fraction_4)
 eval instant at 10m histogram_sum(scalar(histogram_fraction(-Inf, +Inf, sum(histogram_fraction_4))) * histogram_fraction_4)
     {} 100
 
+# Apply multiplication and division operator to histogram.
+load 10m
+    histogram_mul_div {{schema:0 count:21 sum:33 z_bucket:3 z_bucket_w:0.001 buckets:[3 3 3] n_buckets:[3 3 3]}}x1
+    float_series_3 3+0x1
+    float_series_0 0+0x1
+
+eval instant at 10m histogram_mul_div*3
+    {} {{schema:0 count:63 sum:99 z_bucket:9 z_bucket_w:0.001 buckets:[9 9 9] n_buckets:[9 9 9]}}
+
+eval instant at 10m 3*histogram_mul_div
+    {} {{schema:0 count:63 sum:99 z_bucket:9 z_bucket_w:0.001 buckets:[9 9 9] n_buckets:[9 9 9]}}
+
+eval instant at 10m histogram_mul_div*float_series_3
+    {} {{schema:0 count:63 sum:99 z_bucket:9 z_bucket_w:0.001 buckets:[9 9 9] n_buckets:[9 9 9]}}
+
+eval instant at 10m float_series_3*histogram_mul_div
+    {} {{schema:0 count:63 sum:99 z_bucket:9 z_bucket_w:0.001 buckets:[9 9 9] n_buckets:[9 9 9]}}
+
+eval instant at 10m histogram_mul_div/3
+    {} {{schema:0 count:7 sum:11 z_bucket:1 z_bucket_w:0.001 buckets:[1 1 1] n_buckets:[1 1 1]}}
+
+eval instant at 10m histogram_mul_div/float_series_3
+    {} {{schema:0 count:7 sum:11 z_bucket:1 z_bucket_w:0.001 buckets:[1 1 1] n_buckets:[1 1 1]}}
+
+eval instant at 10m histogram_mul_div*0
+    {} {{schema:0 count:0 sum:0 z_bucket:0 z_bucket_w:0.001 buckets:[0 0 0] n_buckets:[0 0 0]}}
+
+eval instant at 10m 0*histogram_mul_div
+    {} {{schema:0 count:0 sum:0 z_bucket:0 z_bucket_w:0.001 buckets:[0 0 0] n_buckets:[0 0 0]}}
+
+eval instant at 10m histogram_mul_div*float_series_0
+    {} {{schema:0 count:0 sum:0 z_bucket:0 z_bucket_w:0.001 buckets:[0 0 0] n_buckets:[0 0 0]}}
+
+eval instant at 10m float_series_0*histogram_mul_div
+    {} {{schema:0 count:0 sum:0 z_bucket:0 z_bucket_w:0.001 buckets:[0 0 0] n_buckets:[0 0 0]}}
+
+# TODO: (NeerajGartia21) remove all the histogram buckets in case of division with zero. See: https://github.com/prometheus/prometheus/issues/13934
+eval instant at 10m histogram_mul_div/0
+    {} {{schema:0 count:Inf sum:Inf z_bucket:Inf z_bucket_w:0.001 buckets:[Inf Inf Inf] n_buckets:[Inf Inf Inf]}}
+
+eval instant at 10m histogram_mul_div/float_series_0
+    {} {{schema:0 count:Inf sum:Inf z_bucket:Inf z_bucket_w:0.001 buckets:[Inf Inf Inf] n_buckets:[Inf Inf Inf]}}
+
+eval instant at 10m histogram_mul_div*0/0
+    {} {{schema:0 count:NaN sum:NaN z_bucket:NaN z_bucket_w:0.001 buckets:[NaN NaN NaN] n_buckets:[NaN NaN NaN]}}
+
 clear
 
 # Counter reset only noticeable in a single bucket.
@@ -748,3 +794,177 @@ eval instant at 5m histogram_quantile(0.5, custom_buckets_histogram)
 
 eval instant at 5m sum(custom_buckets_histogram)
     {} {{schema:-53 sum:5 count:4 custom_values:[5 10] buckets:[1 2 1]}}
+
+clear
+
+# Test 'this native histogram metric is not a gauge' warning for rate
+load 30s
+    some_metric {{schema:0 sum:1 count:1 buckets:[1] counter_reset_hint:gauge}} {{schema:0 sum:2 count:2 buckets:[2] counter_reset_hint:gauge}} {{schema:0 sum:3 count:3 buckets:[3] counter_reset_hint:gauge}}
+
+# Test the case where we only have two points for rate
+eval_warn instant at 30s rate(some_metric[30s])
+    {} {{count:0.03333333333333333 sum:0.03333333333333333 buckets:[0.03333333333333333]}}
+
+# Test the case where we have more than two points for rate
+eval_warn instant at 1m rate(some_metric[1m])
+    {} {{count:0.03333333333333333 sum:0.03333333333333333 buckets:[0.03333333333333333]}}
+
+clear
+
+# Test rate() over mixed exponential and custom buckets.
+load 30s
+    some_metric {{schema:0 sum:1 count:1 buckets:[1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} {{schema:0 sum:5 count:4 buckets:[1 2 1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
+
+# Start and end with exponential, with custom in the middle.
+eval_warn instant at 1m rate(some_metric[1m])
+    # Should produce no results.
+
+# Start and end with custom, with exponential in the middle.
+eval_warn instant at 1m30s rate(some_metric[1m])
+    # Should produce no results.
+
+# Start with custom, end with exponential.
+eval_warn instant at 1m rate(some_metric[30s])
+    # Should produce no results.
+
+# Start with exponential, end with custom.
+eval_warn instant at 30s rate(some_metric[30s])
+    # Should produce no results.
+
+clear
+
+# Histogram with constant buckets.
+load 1m
+    const_histogram {{schema:0 sum:1 count:1 buckets:[1 1 1]}} {{schema:0 sum:1 count:1 buckets:[1 1 1]}} {{schema:0 sum:1 count:1 buckets:[1 1 1]}} {{schema:0 sum:1 count:1 buckets:[1 1 1]}} {{schema:0 sum:1 count:1 buckets:[1 1 1]}}
+
+# There is no change to the bucket count over time, thus rate is 0 in each bucket.
+# However native histograms do not represent empty buckets, so here the zeros are implicit.
+eval instant at 5m rate(const_histogram[5m])
+    {} {{schema:0 sum:0 count:0}}
+
+# Zero buckets mean no observations, thus the denominator in the average is 0
+# leading to 0/0, which is NaN.
+eval instant at 5m histogram_avg(rate(const_histogram[5m]))
+    {} NaN
+
+# Zero buckets mean no observations, so count is 0.
+eval instant at 5m histogram_count(rate(const_histogram[5m]))
+    {} 0.0
+
+# Zero buckets mean no observations and empty histogram has a sum of 0 by definition.
+eval instant at 5m histogram_sum(rate(const_histogram[5m]))
+    {} 0.0
+
+# Zero buckets mean no observations, thus the denominator in the fraction is 0,
+# leading to 0/0, which is NaN.
+eval instant at 5m histogram_fraction(0.0, 1.0, rate(const_histogram[5m]))
+    {} NaN
+
+# Workaround to calculate the observation count corresponding to NaN fraction.
+eval instant at 5m histogram_count(rate(const_histogram[5m])) == 0.0 or histogram_fraction(0.0, 1.0, rate(const_histogram[5m])) * histogram_count(rate(const_histogram[5m]))
+    {} 0.0
+
+# Zero buckets mean no observations, so there is no value that observations fall below,
+# which means that any quantile is a NaN.
+eval instant at 5m histogram_quantile(1.0, rate(const_histogram[5m]))
+    {} NaN
+
+# Zero buckets mean no observations, so there is no standard deviation.
+eval instant at 5m histogram_stddev(rate(const_histogram[5m]))
+    {} NaN
+
+# Zero buckets mean no observations, so there is no standard variance.
+eval instant at 5m histogram_stdvar(rate(const_histogram[5m]))
+    {} NaN
+
+clear
+
+# Test mixing exponential and custom buckets.
+load 6m
+  metric{series="exponential"}         {{sum:4 count:3 buckets:[1 2 1]}}  _                                                                 {{sum:4 count:3 buckets:[1 2 1]}}
+  metric{series="other-exponential"}   {{sum:3 count:2 buckets:[1 1 1]}}  _                                                                 {{sum:3 count:2 buckets:[1 1 1]}}
+  metric{series="custom"}              _                                  {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}     {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
+  metric{series="other-custom"}        _                                  {{schema:-53 sum:15 count:2 custom_values:[5 10] buckets:[0 2]}}  {{schema:-53 sum:15 count:2 custom_values:[5 10] buckets:[0 2]}}
+
+# T=0: only exponential
+# T=6: only custom
+# T=12: mixed, should be ignored and emit a warning
+eval_warn range from 0 to 12m step 6m sum(metric)
+  {} {{sum:7 count:5 buckets:[2 3 2]}} {{schema:-53 sum:16 count:3 custom_values:[5 10] buckets:[1 2]}} _
+
+eval_warn range from 0 to 12m step 6m avg(metric)
+  {} {{sum:3.5 count:2.5 buckets:[1 1.5 1]}} {{schema:-53 sum:8 count:1.5 custom_values:[5 10] buckets:[0.5 1]}} _
+
+clear
+
+# Test incompatible custom bucket schemas.
+load 6m
+  metric{series="1"} _                                                             {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
+  metric{series="2"} {{schema:-53 sum:1 count:1 custom_values:[2] buckets:[1]}}    _                                                             {{schema:-53 sum:1 count:1 custom_values:[2] buckets:[1]}}
+  metric{series="3"} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
+
+# T=0: incompatible, should be ignored and emit a warning
+# T=6: compatible
+# T=12: incompatible followed by compatible, should be ignored and emit a warning
+eval_warn range from 0 to 12m step 6m sum(metric)
+  {} _ {{schema:-53 sum:2 count:2 custom_values:[5 10] buckets:[2]}} _
+
+eval_warn range from 0 to 12m step 6m avg(metric)
+  {} _ {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}} _
+
+clear
+
+load 1m
+  metric{group="just-floats", series="1"} 2
+  metric{group="just-floats", series="2"} 3
+  metric{group="just-exponential-histograms", series="1"} {{sum:3 count:4 buckets:[1 2 1]}}
+  metric{group="just-exponential-histograms", series="2"} {{sum:2 count:3 buckets:[1 1 1]}}
+  metric{group="just-custom-histograms", series="1"} {{schema:-53 sum:1 count:1 custom_values:[2] buckets:[1]}}
+  metric{group="just-custom-histograms", series="2"} {{schema:-53 sum:3 count:4 custom_values:[2] buckets:[7]}}
+  metric{group="floats-and-histograms", series="1"} 2
+  metric{group="floats-and-histograms", series="2"} {{sum:2 count:3 buckets:[1 1 1]}}
+  metric{group="exponential-and-custom-histograms", series="1"} {{sum:2 count:3 buckets:[1 1 1]}}
+  metric{group="exponential-and-custom-histograms", series="2"} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
+  metric{group="incompatible-custom-histograms", series="1"} {{schema:-53 sum:1 count:1 custom_values:[5 10] buckets:[1]}}
+  metric{group="incompatible-custom-histograms", series="2"} {{schema:-53 sum:1 count:1 custom_values:[2] buckets:[1]}}
+
+eval_warn instant at 0 sum by (group) (metric)
+  {group="just-floats"} 5
+  {group="just-exponential-histograms"} {{sum:5 count:7 buckets:[2 3 2]}}
+  {group="just-custom-histograms"} {{schema:-53 sum:4 count:5 custom_values:[2] buckets:[8]}}
+
+clear
+
+# Test native histograms with sum, count, avg.
+load 10m
+    histogram_sum{idx="0"} {{schema:0 count:25 sum:1234.5 z_bucket:4 z_bucket_w:0.001 buckets:[1 2 0 1 1] n_buckets:[2 4 0 0 1 9]}}x1
+    histogram_sum{idx="1"} {{schema:0 count:41 sum:2345.6 z_bucket:5 z_bucket_w:0.001 buckets:[1 3 1 2 1 1 1] n_buckets:[0 1 4 2 7 0 0 0 0 5 5 2]}}x1
+    histogram_sum{idx="2"} {{schema:0 count:41 sum:1111.1 z_bucket:5 z_bucket_w:0.001 buckets:[1 3 1 2 1 1 1] n_buckets:[0 1 4 2 7 0 0 0 0 5 5 2]}}x1
+    histogram_sum{idx="3"} {{schema:1 count:0}}x1
+    histogram_sum_float{idx="0"} 42.0x1
+
+eval instant at 10m sum(histogram_sum)
+    {} {{schema:0 count:107 sum:4691.2 z_bucket:14 z_bucket_w:0.001 buckets:[3 8 2 5 3 2 2] n_buckets:[2 6 8 4 15 9 0 0 0 10 10 4]}}
+
+eval_warn instant at 10m sum({idx="0"})
+
+eval instant at 10m sum(histogram_sum{idx="0"} + ignoring(idx) histogram_sum{idx="1"} + ignoring(idx) histogram_sum{idx="2"} + ignoring(idx) histogram_sum{idx="3"})
+    {} {{schema:0 count:107 sum:4691.2 z_bucket:14 z_bucket_w:0.001 buckets:[3 8 2 5 3 2 2] n_buckets:[2 6 8 4 15 9 0 0 0 10 10 4]}}
+
+eval instant at 10m count(histogram_sum)
+    {} 4
+
+eval instant at 10m avg(histogram_sum)
+    {} {{schema:0 count:26.75 sum:1172.8 z_bucket:3.5 z_bucket_w:0.001 buckets:[0.75 2 0.5 1.25 0.75 0.5 0.5] n_buckets:[0.5 1.5 2 1 3.75 2.25 0 0 0 2.5 2.5 1]}}
+
+clear
+
+# Test native histograms with sum_over_time, avg_over_time.
+load 1m
+    histogram_sum_over_time {{schema:0 count:25 sum:1234.5 z_bucket:4 z_bucket_w:0.001 buckets:[1 2 0 1 1] n_buckets:[2 4 0 0 1 9]}} {{schema:0 count:41 sum:2345.6 z_bucket:5 z_bucket_w:0.001 buckets:[1 3 1 2 1 1 1] n_buckets:[0 1 4 2 7 0 0 0 0 5 5 2]}} {{schema:0 count:41 sum:1111.1 z_bucket:5 z_bucket_w:0.001 buckets:[1 3 1 2 1 1 1] n_buckets:[0 1 4 2 7 0 0 0 0 5 5 2]}} {{schema:1 count:0}}
+
+eval instant at 3m sum_over_time(histogram_sum_over_time[3m:1m])
+    {} {{schema:0 count:107 sum:4691.2 z_bucket:14 z_bucket_w:0.001 buckets:[3 8 2 5 3 2 2] n_buckets:[2 6 8 4 15 9 0 0 0 10 10 4]}}
+
+eval instant at 3m avg_over_time(histogram_sum_over_time[3m:1m])
+    {} {{schema:0 count:26.75 sum:1172.8 z_bucket:3.5 z_bucket_w:0.001 buckets:[0.75 2 0.5 1.25 0.75 0.5 0.5] n_buckets:[0.5 1.5 2 1 3.75 2.25 0 0 0 2.5 2.5 1]}}

promql/value.go

@@ -68,6 +68,9 @@ type Series struct {
 	Metric     labels.Labels `json:"metric"`
 	Floats     []FPoint      `json:"values,omitempty"`
 	Histograms []HPoint      `json:"histograms,omitempty"`
+	// DropName is used to indicate whether the __name__ label should be dropped
+	// as part of the query evaluation.
+	DropName bool `json:"-"`
 }
 
 func (s Series) String() string {
@@ -194,6 +197,9 @@ type Sample struct {
 	H *histogram.FloatHistogram
 
 	Metric labels.Labels
+	// DropName is used to indicate whether the __name__ label should be dropped
+	// as part of the query evaluation.
+	DropName bool
 }
 
 func (s Sample) String() string {

rules/alerting_test.go

@@ -36,7 +36,9 @@ import (
 	"github.com/prometheus/prometheus/util/testutil"
 )
 
-var testEngine = promql.NewEngine(promql.EngineOpts{
+func testEngine(tb testing.TB) *promql.Engine {
+	tb.Helper()
+	return promqltest.NewTestEngineWithOpts(tb, promql.EngineOpts{
 		Logger:                   nil,
 		Reg:                      nil,
 		MaxSamples:               10000,
@@ -45,7 +47,8 @@ var testEngine = promql.NewEngine(promql.EngineOpts{
 		EnableAtModifier:         true,
 		EnableNegativeOffset:     true,
 		EnablePerStepStats:       true,
-})
+	})
+}
 
 func TestAlertingRuleState(t *testing.T) {
 	tests := []struct {
@@ -225,12 +228,14 @@ func TestAlertingRuleLabelsUpdate(t *testing.T) {
 		},
 	}
 
+	ng := testEngine(t)
+
 	baseTime := time.Unix(0, 0)
 	for i, result := range results {
 		t.Logf("case %d", i)
 		evalTime := baseTime.Add(time.Duration(i) * time.Minute)
 		result[0].T = timestamp.FromTime(evalTime)
-		res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0)
+		res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0)
 		require.NoError(t, err)
 
 		var filteredRes promql.Vector // After removing 'ALERTS_FOR_STATE' samples.
@@ -247,7 +252,7 @@ func TestAlertingRuleLabelsUpdate(t *testing.T) {
 		testutil.RequireEqual(t, result, filteredRes)
 	}
 	evalTime := baseTime.Add(time.Duration(len(results)) * time.Minute)
-	res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0)
+	res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0)
 	require.NoError(t, err)
 	require.Empty(t, res)
 }
@@ -309,13 +314,15 @@ func TestAlertingRuleExternalLabelsInTemplate(t *testing.T) {
 		},
 	}
 
+	ng := testEngine(t)
+
 	evalTime := time.Unix(0, 0)
 	result[0].T = timestamp.FromTime(evalTime)
 	result[1].T = timestamp.FromTime(evalTime)
 
 	var filteredRes promql.Vector // After removing 'ALERTS_FOR_STATE' samples.
 	res, err := ruleWithoutExternalLabels.Eval(
-		context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0,
+		context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0,
 	)
 	require.NoError(t, err)
 	for _, smpl := range res {
@@ -329,7 +336,7 @@ func TestAlertingRuleExternalLabelsInTemplate(t *testing.T) {
 	}
 
 	res, err = ruleWithExternalLabels.Eval(
-		context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0,
+		context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0,
 	)
 	require.NoError(t, err)
 	for _, smpl := range res {
@@ -406,9 +413,11 @@ func TestAlertingRuleExternalURLInTemplate(t *testing.T) {
 	result[0].T = timestamp.FromTime(evalTime)
 	result[1].T = timestamp.FromTime(evalTime)
 
+	ng := testEngine(t)
+
 	var filteredRes promql.Vector // After removing 'ALERTS_FOR_STATE' samples.
 	res, err := ruleWithoutExternalURL.Eval(
-		context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0,
+		context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0,
 	)
 	require.NoError(t, err)
 	for _, smpl := range res {
@@ -422,7 +431,7 @@ func TestAlertingRuleExternalURLInTemplate(t *testing.T) {
 	}
 
 	res, err = ruleWithExternalURL.Eval(
-		context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0,
+		context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0,
 	)
 	require.NoError(t, err)
 	for _, smpl := range res {
@@ -475,9 +484,11 @@ func TestAlertingRuleEmptyLabelFromTemplate(t *testing.T) {
 	evalTime := time.Unix(0, 0)
 	result[0].T = timestamp.FromTime(evalTime)
 
+	ng := testEngine(t)
+
 	var filteredRes promql.Vector // After removing 'ALERTS_FOR_STATE' samples.
 	res, err := rule.Eval(
-		context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0,
+		context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0,
 	)
 	require.NoError(t, err)
 	for _, smpl := range res {
@@ -520,6 +531,8 @@ instance: {{ $v.Labels.instance }}, value: {{ printf "%.0f" $v.Value }};
 	)
 	evalTime := time.Unix(0, 0)
 
+	ng := testEngine(t)
+
 	startQueryCh := make(chan struct{})
 	getDoneCh := make(chan struct{})
 	slowQueryFunc := func(ctx context.Context, q string, ts time.Time) (promql.Vector, error) {
@@ -533,7 +546,7 @@ instance: {{ $v.Labels.instance }}, value: {{ printf "%.0f" $v.Value }};
 				require.Fail(t, "unexpected blocking when template expanding.")
 			}
 		}
-		return EngineQueryFunc(testEngine, storage)(ctx, q, ts)
+		return EngineQueryFunc(ng, storage)(ctx, q, ts)
 	}
 	go func() {
 		<-startQueryCh
@@ -578,7 +591,7 @@ func TestAlertingRuleDuplicate(t *testing.T) {
 		Timeout:    10 * time.Second,
 	}
 
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
 	defer cancelCtx()
 
@@ -642,13 +655,13 @@ func TestAlertingRuleLimit(t *testing.T) {
 	)
 
 	evalTime := time.Unix(0, 0)
-
+	ng := testEngine(t)
 	for _, test := range tests {
-		switch _, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, test.limit); {
+		switch _, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, test.limit); {
 		case err != nil:
 			require.EqualError(t, err, test.err)
 		case test.err != "":
-			t.Errorf("Expected errror %s, got none", test.err)
+			t.Errorf("Expected error %s, got none", test.err)
 		}
 	}
 }
@@ -866,12 +879,13 @@ func TestKeepFiringFor(t *testing.T) {
 		},
 	}
 
+	ng := testEngine(t)
 	baseTime := time.Unix(0, 0)
 	for i, result := range results {
 		t.Logf("case %d", i)
 		evalTime := baseTime.Add(time.Duration(i) * time.Minute)
 		result[0].T = timestamp.FromTime(evalTime)
-		res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0)
+		res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0)
 		require.NoError(t, err)
 
 		var filteredRes promql.Vector // After removing 'ALERTS_FOR_STATE' samples.
@@ -888,7 +902,7 @@ func TestKeepFiringFor(t *testing.T) {
 		testutil.RequireEqual(t, result, filteredRes)
 	}
 	evalTime := baseTime.Add(time.Duration(len(results)) * time.Minute)
-	res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0)
+	res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0)
 	require.NoError(t, err)
 	require.Empty(t, res)
 }
@@ -923,9 +937,10 @@ func TestPendingAndKeepFiringFor(t *testing.T) {
 		F: 1,
 	}
 
+	ng := testEngine(t)
 	baseTime := time.Unix(0, 0)
 	result.T = timestamp.FromTime(baseTime)
-	res, err := rule.Eval(context.TODO(), 0, baseTime, EngineQueryFunc(testEngine, storage), nil, 0)
+	res, err := rule.Eval(context.TODO(), 0, baseTime, EngineQueryFunc(ng, storage), nil, 0)
 	require.NoError(t, err)
 
 	require.Len(t, res, 2)
@@ -940,7 +955,7 @@ func TestPendingAndKeepFiringFor(t *testing.T) {
 	}
 
 	evalTime := baseTime.Add(time.Minute)
-	res, err = rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0)
+	res, err = rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0)
 	require.NoError(t, err)
 	require.Empty(t, res)
 }

rules/manager_test.go

@@ -158,12 +158,13 @@ func TestAlertingRule(t *testing.T) {
 		},
 	}
 
+	ng := testEngine(t)
 	for i, test := range tests {
 		t.Logf("case %d", i)
 
 		evalTime := baseTime.Add(test.time)
 
-		res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, 0)
+		res, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, 0)
 		require.NoError(t, err)
 
 		var filteredRes promql.Vector // After removing 'ALERTS_FOR_STATE' samples.
@@ -299,6 +300,7 @@ func TestForStateAddSamples(t *testing.T) {
 				},
 			}
 
+			ng := testEngine(t)
 			var forState float64
 			for i, test := range tests {
 				t.Logf("case %d", i)
@@ -311,7 +313,7 @@ func TestForStateAddSamples(t *testing.T) {
 					forState = float64(value.StaleNaN)
 				}
 
-				res, err := rule.Eval(context.TODO(), queryOffset, evalTime, EngineQueryFunc(testEngine, storage), nil, 0)
+				res, err := rule.Eval(context.TODO(), queryOffset, evalTime, EngineQueryFunc(ng, storage), nil, 0)
 				require.NoError(t, err)
 
 				var filteredRes promql.Vector // After removing 'ALERTS' samples.
@@ -366,8 +368,9 @@ func TestForStateRestore(t *testing.T) {
 			expr, err := parser.ParseExpr(`http_requests{group="canary", job="app-server"} < 100`)
 			require.NoError(t, err)
 
+			ng := testEngine(t)
 			opts := &ManagerOptions{
-				QueryFunc:       EngineQueryFunc(testEngine, storage),
+				QueryFunc:       EngineQueryFunc(ng, storage),
 				Appendable:      storage,
 				Queryable:       storage,
 				Context:         context.Background(),
@@ -538,7 +541,7 @@ func TestStaleness(t *testing.T) {
 			MaxSamples: 10,
 			Timeout:    10 * time.Second,
 		}
-		engine := promql.NewEngine(engineOpts)
+		engine := promqltest.NewTestEngineWithOpts(t, engineOpts)
 		opts := &ManagerOptions{
 			QueryFunc:  EngineQueryFunc(engine, st),
 			Appendable: st,
@@ -772,7 +775,7 @@ func TestUpdate(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	ruleManager := NewManager(&ManagerOptions{
 		Appendable: st,
 		Queryable:  st,
@@ -910,7 +913,7 @@ func TestNotify(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(engineOpts)
+	engine := promqltest.NewTestEngineWithOpts(t, engineOpts)
 	var lastNotified []*Alert
 	notifyFunc := func(ctx context.Context, expr string, alerts ...*Alert) {
 		lastNotified = alerts
@@ -985,7 +988,7 @@ func TestMetricsUpdate(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	ruleManager := NewManager(&ManagerOptions{
 		Appendable: storage,
 		Queryable:  storage,
@@ -1059,7 +1062,7 @@ func TestGroupStalenessOnRemoval(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	ruleManager := NewManager(&ManagerOptions{
 		Appendable: storage,
 		Queryable:  storage,
@@ -1136,7 +1139,7 @@ func TestMetricsStalenessOnManagerShutdown(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	ruleManager := NewManager(&ManagerOptions{
 		Appendable: storage,
 		Queryable:  storage,
@@ -1238,7 +1241,7 @@ func TestRuleHealthUpdates(t *testing.T) {
 		MaxSamples: 10,
 		Timeout:    10 * time.Second,
 	}
-	engine := promql.NewEngine(engineOpts)
+	engine := promqltest.NewTestEngineWithOpts(t, engineOpts)
 	opts := &ManagerOptions{
 		QueryFunc:  EngineQueryFunc(engine, st),
 		Appendable: st,
@@ -1335,9 +1338,10 @@ func TestRuleGroupEvalIterationFunc(t *testing.T) {
 		},
 	}
 
+	ng := testEngine(t)
 	testFunc := func(tst testInput) {
 		opts := &ManagerOptions{
-			QueryFunc:       EngineQueryFunc(testEngine, storage),
+			QueryFunc:       EngineQueryFunc(ng, storage),
 			Appendable:      storage,
 			Queryable:       storage,
 			Context:         context.Background(),
@@ -1421,8 +1425,9 @@ func TestNativeHistogramsInRecordingRules(t *testing.T) {
 	}
 	require.NoError(t, app.Commit())
 
+	ng := testEngine(t)
 	opts := &ManagerOptions{
-		QueryFunc:  EngineQueryFunc(testEngine, storage),
+		QueryFunc:  EngineQueryFunc(ng, storage),
 		Appendable: storage,
 		Queryable:  storage,
 		Context:    context.Background(),

rules/recording_test.go

@@ -123,10 +123,11 @@ func TestRuleEval(t *testing.T) {
 	storage := setUpRuleEvalTest(t)
 	t.Cleanup(func() { storage.Close() })
 
+	ng := testEngine(t)
 	for _, scenario := range ruleEvalTestScenarios {
 		t.Run(scenario.name, func(t *testing.T) {
 			rule := NewRecordingRule("test_rule", scenario.expr, scenario.ruleLabels)
-			result, err := rule.Eval(context.TODO(), 0, ruleEvaluationTime, EngineQueryFunc(testEngine, storage), nil, 0)
+			result, err := rule.Eval(context.TODO(), 0, ruleEvaluationTime, EngineQueryFunc(ng, storage), nil, 0)
 			require.NoError(t, err)
 			testutil.RequireEqual(t, scenario.expected, result)
 		})
@@ -137,6 +138,7 @@ func BenchmarkRuleEval(b *testing.B) {
 	storage := setUpRuleEvalTest(b)
 	b.Cleanup(func() { storage.Close() })
 
+	ng := testEngine(b)
 	for _, scenario := range ruleEvalTestScenarios {
 		b.Run(scenario.name, func(b *testing.B) {
 			rule := NewRecordingRule("test_rule", scenario.expr, scenario.ruleLabels)
@@ -144,7 +146,7 @@ func BenchmarkRuleEval(b *testing.B) {
 			b.ResetTimer()
 
 			for i := 0; i < b.N; i++ {
-				_, err := rule.Eval(context.TODO(), 0, ruleEvaluationTime, EngineQueryFunc(testEngine, storage), nil, 0)
+				_, err := rule.Eval(context.TODO(), 0, ruleEvaluationTime, EngineQueryFunc(ng, storage), nil, 0)
 				if err != nil {
 					require.NoError(b, err)
 				}
@@ -165,7 +167,7 @@ func TestRuleEvalDuplicate(t *testing.T) {
 		Timeout:    10 * time.Second,
 	}
 
-	engine := promql.NewEngine(opts)
+	engine := promqltest.NewTestEngineWithOpts(t, opts)
 	ctx, cancelCtx := context.WithCancel(context.Background())
 	defer cancelCtx()
 
@@ -212,10 +214,11 @@ func TestRecordingRuleLimit(t *testing.T) {
 		labels.FromStrings("test", "test"),
 	)
 
+	ng := testEngine(t)
 	evalTime := time.Unix(0, 0)
 
 	for _, test := range tests {
-		switch _, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(testEngine, storage), nil, test.limit); {
+		switch _, err := rule.Eval(context.TODO(), 0, evalTime, EngineQueryFunc(ng, storage), nil, test.limit); {
 		case err != nil:
 			require.EqualError(t, err, test.err)
 		case test.err != "":

scrape/clientprotobuf.go

@@ -23,7 +23,7 @@ import (
 	dto "github.com/prometheus/client_model/go"
 )
 
-// Write a MetricFamily into a protobuf.
+// MetricFamilyToProtobuf writes a MetricFamily into a protobuf.
 // This function is intended for testing scraping by providing protobuf serialized input.
 func MetricFamilyToProtobuf(metricFamily *dto.MetricFamily) ([]byte, error) {
 	buffer := &bytes.Buffer{}
@@ -34,7 +34,7 @@ func MetricFamilyToProtobuf(metricFamily *dto.MetricFamily) ([]byte, error) {
 	return buffer.Bytes(), nil
 }
 
-// Append a MetricFamily protobuf representation to a buffer.
+// AddMetricFamilyToProtobuf appends a MetricFamily protobuf representation to a buffer.
 // This function is intended for testing scraping by providing protobuf serialized input.
 func AddMetricFamilyToProtobuf(buffer *bytes.Buffer, metricFamily *dto.MetricFamily) error {
 	protoBuf, err := proto.Marshal(metricFamily)

scrape/manager.go

@@ -93,6 +93,8 @@ type Options struct {
 	skipOffsetting bool
 }
 
+const DefaultNameEscapingScheme = model.ValueEncodingEscaping
+
 // Manager maintains a set of scrape pools and manages start/stop cycles
 // when receiving new target groups from the discovery manager.
 type Manager struct {
@@ -140,7 +142,7 @@ func (m *Manager) UnregisterMetrics() {
 
 func (m *Manager) reloader() {
 	reloadIntervalDuration := m.opts.DiscoveryReloadInterval
-	if reloadIntervalDuration < model.Duration(5*time.Second) {
+	if reloadIntervalDuration == model.Duration(0) {
 		reloadIntervalDuration = model.Duration(5 * time.Second)
 	}
 

scrape/manager_test.go

@@ -20,6 +20,7 @@ import (
 	"net/http/httptest"
 	"net/url"
 	"os"
+	"sort"
 	"strconv"
 	"sync"
 	"testing"
@@ -36,6 +37,7 @@ import (
 
 	"github.com/prometheus/prometheus/config"
 	"github.com/prometheus/prometheus/discovery"
+	_ "github.com/prometheus/prometheus/discovery/file"
 	"github.com/prometheus/prometheus/discovery/targetgroup"
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/prometheus/prometheus/model/relabel"
@@ -722,8 +724,6 @@ func TestManagerCTZeroIngestion(t *testing.T) {
 		name                  string
 		counterSample         *dto.Counter
 		enableCTZeroIngestion bool
-
-		expectedValues []float64
 	}{
 		{
 			name: "disabled with CT on counter",
@@ -732,7 +732,6 @@ func TestManagerCTZeroIngestion(t *testing.T) {
 				// Timestamp does not matter as long as it exists in this test.
 				CreatedTimestamp: timestamppb.Now(),
 			},
-			expectedValues: []float64{1.0},
 		},
 		{
 			name: "enabled with CT on counter",
@@ -742,7 +741,6 @@ func TestManagerCTZeroIngestion(t *testing.T) {
 				CreatedTimestamp: timestamppb.Now(),
 			},
 			enableCTZeroIngestion: true,
-			expectedValues:        []float64{0.0, 1.0},
 		},
 		{
 			name: "enabled without CT on counter",
@@ -750,7 +748,6 @@ func TestManagerCTZeroIngestion(t *testing.T) {
 				Value: proto.Float64(1.0),
 			},
 			enableCTZeroIngestion: true,
-			expectedValues:        []float64{1.0},
 		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
@@ -817,44 +814,42 @@ func TestManagerCTZeroIngestion(t *testing.T) {
 			})
 			scrapeManager.reload()
 
+			var got []float64
 			// Wait for one scrape.
 			ctx, cancel := context.WithTimeout(context.Background(), 1*time.Minute)
 			defer cancel()
 			require.NoError(t, runutil.Retry(100*time.Millisecond, ctx.Done(), func() error {
-				if countFloatSamples(app, mName) != len(tc.expectedValues) {
-					return fmt.Errorf("expected %v samples", tc.expectedValues)
-				}
-				return nil
-			}), "after 1 minute")
-			scrapeManager.Stop()
-
-			require.Equal(t, tc.expectedValues, getResultFloats(app, mName))
-		})
-	}
-}
-
-func countFloatSamples(a *collectResultAppender, expectedMetricName string) (count int) {
-	a.mtx.Lock()
-	defer a.mtx.Unlock()
-
-	for _, f := range a.resultFloats {
-		if f.metric.Get(model.MetricNameLabel) == expectedMetricName {
-			count++
-		}
-	}
-	return count
-}
-
-func getResultFloats(app *collectResultAppender, expectedMetricName string) (result []float64) {
 				app.mtx.Lock()
 				defer app.mtx.Unlock()
 
+				// Check if scrape happened and grab the relevant samples, they have to be there - or it's a bug
+				// and it's not worth waiting.
 				for _, f := range app.resultFloats {
-		if f.metric.Get(model.MetricNameLabel) == expectedMetricName {
+					if f.metric.Get(model.MetricNameLabel) == mName {
-			result = append(result, f.f)
+						got = append(got, f.f)
 					}
 				}
-	return result
+				if len(app.resultFloats) > 0 {
+					return nil
+				}
+				return fmt.Errorf("expected some samples, got none")
+			}), "after 1 minute")
+			scrapeManager.Stop()
+
+			// Check for zero samples, assuming we only injected always one sample.
+			// Did it contain CT to inject? If yes, was CT zero enabled?
+			if tc.counterSample.CreatedTimestamp.IsValid() && tc.enableCTZeroIngestion {
+				require.Len(t, got, 2)
+				require.Equal(t, 0.0, got[0])
+				require.Equal(t, tc.counterSample.GetValue(), got[1])
+				return
+			}
+
+			// Expect only one, valid sample.
+			require.Len(t, got, 1)
+			require.Equal(t, tc.counterSample.GetValue(), got[0])
+		})
+	}
 }
 
 func TestUnregisterMetrics(t *testing.T) {
@@ -869,3 +864,414 @@ func TestUnregisterMetrics(t *testing.T) {
 		manager.UnregisterMetrics()
 	}
 }
+
+func applyConfig(
+	t *testing.T,
+	config string,
+	scrapeManager *Manager,
+	discoveryManager *discovery.Manager,
+) {
+	t.Helper()
+
+	cfg := loadConfiguration(t, config)
+	require.NoError(t, scrapeManager.ApplyConfig(cfg))
+
+	c := make(map[string]discovery.Configs)
+	scfgs, err := cfg.GetScrapeConfigs()
+	require.NoError(t, err)
+	for _, v := range scfgs {
+		c[v.JobName] = v.ServiceDiscoveryConfigs
+	}
+	require.NoError(t, discoveryManager.ApplyConfig(c))
+}
+
+func runManagers(t *testing.T, ctx context.Context) (*discovery.Manager, *Manager) {
+	t.Helper()
+
+	reg := prometheus.NewRegistry()
+	sdMetrics, err := discovery.RegisterSDMetrics(reg, discovery.NewRefreshMetrics(reg))
+	require.NoError(t, err)
+	discoveryManager := discovery.NewManager(
+		ctx,
+		log.NewNopLogger(),
+		reg,
+		sdMetrics,
+		discovery.Updatert(100*time.Millisecond),
+	)
+	scrapeManager, err := NewManager(
+		&Options{DiscoveryReloadInterval: model.Duration(100 * time.Millisecond)},
+		nil,
+		nopAppendable{},
+		prometheus.NewRegistry(),
+	)
+	require.NoError(t, err)
+	go discoveryManager.Run()
+	go scrapeManager.Run(discoveryManager.SyncCh())
+	return discoveryManager, scrapeManager
+}
+
+func writeIntoFile(t *testing.T, content, filePattern string) *os.File {
+	t.Helper()
+
+	file, err := os.CreateTemp("", filePattern)
+	require.NoError(t, err)
+	_, err = file.WriteString(content)
+	require.NoError(t, err)
+	return file
+}
+
+func requireTargets(
+	t *testing.T,
+	scrapeManager *Manager,
+	jobName string,
+	waitToAppear bool,
+	expectedTargets []string,
+) {
+	t.Helper()
+
+	require.Eventually(t, func() bool {
+		targets, ok := scrapeManager.TargetsActive()[jobName]
+		if !ok {
+			if waitToAppear {
+				return false
+			}
+			t.Fatalf("job %s shouldn't be dropped", jobName)
+		}
+		if expectedTargets == nil {
+			return targets == nil
+		}
+		if len(targets) != len(expectedTargets) {
+			return false
+		}
+		sTargets := []string{}
+		for _, t := range targets {
+			sTargets = append(sTargets, t.String())
+		}
+		sort.Strings(expectedTargets)
+		sort.Strings(sTargets)
+		for i, t := range sTargets {
+			if t != expectedTargets[i] {
+				return false
+			}
+		}
+		return true
+	}, 1*time.Second, 100*time.Millisecond)
+}
+
+// TestTargetDisappearsAfterProviderRemoved makes sure that when a provider is dropped, (only) its targets are dropped.
+func TestTargetDisappearsAfterProviderRemoved(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	myJob := "my-job"
+	myJobSDTargetURL := "my:9876"
+	myJobStaticTargetURL := "my:5432"
+
+	sdFileContent := fmt.Sprintf(`[{"targets": ["%s"]}]`, myJobSDTargetURL)
+	sDFile := writeIntoFile(t, sdFileContent, "*targets.json")
+
+	baseConfig := `
+scrape_configs:
+- job_name: %s
+  static_configs:
+  - targets: ['%s']
+  file_sd_configs:
+  - files: ['%s']
+`
+
+	discoveryManager, scrapeManager := runManagers(t, ctx)
+	defer scrapeManager.Stop()
+
+	applyConfig(
+		t,
+		fmt.Sprintf(
+			baseConfig,
+			myJob,
+			myJobStaticTargetURL,
+			sDFile.Name(),
+		),
+		scrapeManager,
+		discoveryManager,
+	)
+	// Make sure the jobs targets are taken into account
+	requireTargets(
+		t,
+		scrapeManager,
+		myJob,
+		true,
+		[]string{
+			fmt.Sprintf("http://%s/metrics", myJobSDTargetURL),
+			fmt.Sprintf("http://%s/metrics", myJobStaticTargetURL),
+		},
+	)
+
+	// Apply a new config where a provider is removed
+	baseConfig = `
+scrape_configs:
+- job_name: %s
+  static_configs:
+  - targets: ['%s']
+`
+	applyConfig(
+		t,
+		fmt.Sprintf(
+			baseConfig,
+			myJob,
+			myJobStaticTargetURL,
+		),
+		scrapeManager,
+		discoveryManager,
+	)
+	// Make sure the corresponding target was dropped
+	requireTargets(
+		t,
+		scrapeManager,
+		myJob,
+		false,
+		[]string{
+			fmt.Sprintf("http://%s/metrics", myJobStaticTargetURL),
+		},
+	)
+
+	// Apply a new config with no providers
+	baseConfig = `
+scrape_configs:
+- job_name: %s
+`
+	applyConfig(
+		t,
+		fmt.Sprintf(
+			baseConfig,
+			myJob,
+		),
+		scrapeManager,
+		discoveryManager,
+	)
+	// Make sure the corresponding target was dropped
+	requireTargets(
+		t,
+		scrapeManager,
+		myJob,
+		false,
+		nil,
+	)
+}
+
+// TestOnlyProviderStaleTargetsAreDropped makes sure that when a job has only one provider with multiple targets
+// and when the provider can no longer discover some of those targets, only those stale targets are dropped.
+func TestOnlyProviderStaleTargetsAreDropped(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	jobName := "my-job"
+	jobTarget1URL := "foo:9876"
+	jobTarget2URL := "foo:5432"
+
+	sdFile1Content := fmt.Sprintf(`[{"targets": ["%s"]}]`, jobTarget1URL)
+	sdFile2Content := fmt.Sprintf(`[{"targets": ["%s"]}]`, jobTarget2URL)
+	sDFile1 := writeIntoFile(t, sdFile1Content, "*targets.json")
+	sDFile2 := writeIntoFile(t, sdFile2Content, "*targets.json")
+
+	baseConfig := `
+scrape_configs:
+- job_name: %s
+  file_sd_configs:
+  - files: ['%s', '%s']
+`
+	discoveryManager, scrapeManager := runManagers(t, ctx)
+	defer scrapeManager.Stop()
+
+	applyConfig(
+		t,
+		fmt.Sprintf(baseConfig, jobName, sDFile1.Name(), sDFile2.Name()),
+		scrapeManager,
+		discoveryManager,
+	)
+
+	// Make sure the job's targets are taken into account
+	requireTargets(
+		t,
+		scrapeManager,
+		jobName,
+		true,
+		[]string{
+			fmt.Sprintf("http://%s/metrics", jobTarget1URL),
+			fmt.Sprintf("http://%s/metrics", jobTarget2URL),
+		},
+	)
+
+	// Apply the same config for the same job but with a non existing file to make the provider
+	// unable to discover some targets
+	applyConfig(
+		t,
+		fmt.Sprintf(baseConfig, jobName, sDFile1.Name(), "/idontexistdoi.json"),
+		scrapeManager,
+		discoveryManager,
+	)
+
+	// The old target should get dropped
+	requireTargets(
+		t,
+		scrapeManager,
+		jobName,
+		false,
+		[]string{fmt.Sprintf("http://%s/metrics", jobTarget1URL)},
+	)
+}
+
+// TestProviderStaleTargetsAreDropped makes sure that when a job has only one provider and when that provider
+// should no longer discover targets, the targets of that provider are dropped.
+// See: https://github.com/prometheus/prometheus/issues/12858
+func TestProviderStaleTargetsAreDropped(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	jobName := "my-job"
+	jobTargetURL := "foo:9876"
+
+	sdFileContent := fmt.Sprintf(`[{"targets": ["%s"]}]`, jobTargetURL)
+	sDFile := writeIntoFile(t, sdFileContent, "*targets.json")
+
+	baseConfig := `
+scrape_configs:
+- job_name: %s
+  file_sd_configs:
+  - files: ['%s']
+`
+	discoveryManager, scrapeManager := runManagers(t, ctx)
+	defer scrapeManager.Stop()
+
+	applyConfig(
+		t,
+		fmt.Sprintf(baseConfig, jobName, sDFile.Name()),
+		scrapeManager,
+		discoveryManager,
+	)
+
+	// Make sure the job's targets are taken into account
+	requireTargets(
+		t,
+		scrapeManager,
+		jobName,
+		true,
+		[]string{
+			fmt.Sprintf("http://%s/metrics", jobTargetURL),
+		},
+	)
+
+	// Apply the same config for the same job but with a non existing file to make the provider
+	// unable to discover some targets
+	applyConfig(
+		t,
+		fmt.Sprintf(baseConfig, jobName, "/idontexistdoi.json"),
+		scrapeManager,
+		discoveryManager,
+	)
+
+	// The old target should get dropped
+	requireTargets(
+		t,
+		scrapeManager,
+		jobName,
+		false,
+		nil,
+	)
+}
+
+// TestOnlyStaleTargetsAreDropped makes sure that when a job has multiple providers, when one of them should no
+// longer discover targets, only the stale targets of that provier are dropped.
+func TestOnlyStaleTargetsAreDropped(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	myJob := "my-job"
+	myJobSDTargetURL := "my:9876"
+	myJobStaticTargetURL := "my:5432"
+	otherJob := "other-job"
+	otherJobTargetURL := "other:1234"
+
+	sdFileContent := fmt.Sprintf(`[{"targets": ["%s"]}]`, myJobSDTargetURL)
+	sDFile := writeIntoFile(t, sdFileContent, "*targets.json")
+
+	baseConfig := `
+scrape_configs:
+- job_name: %s
+  static_configs:
+  - targets: ['%s']
+  file_sd_configs:
+  - files: ['%s']
+- job_name: %s
+  static_configs:
+  - targets: ['%s']
+`
+
+	discoveryManager, scrapeManager := runManagers(t, ctx)
+	defer scrapeManager.Stop()
+
+	// Apply the initial config with an existing file
+	applyConfig(
+		t,
+		fmt.Sprintf(
+			baseConfig,
+			myJob,
+			myJobStaticTargetURL,
+			sDFile.Name(),
+			otherJob,
+			otherJobTargetURL,
+		),
+		scrapeManager,
+		discoveryManager,
+	)
+	// Make sure the jobs targets are taken into account
+	requireTargets(
+		t,
+		scrapeManager,
+		myJob,
+		true,
+		[]string{
+			fmt.Sprintf("http://%s/metrics", myJobSDTargetURL),
+			fmt.Sprintf("http://%s/metrics", myJobStaticTargetURL),
+		},
+	)
+	requireTargets(
+		t,
+		scrapeManager,
+		otherJob,
+		true,
+		[]string{fmt.Sprintf("http://%s/metrics", otherJobTargetURL)},
+	)
+
+	// Apply the same config with a non existing file for myJob
+	applyConfig(
+		t,
+		fmt.Sprintf(
+			baseConfig,
+			myJob,
+			myJobStaticTargetURL,
+			"/idontexistdoi.json",
+			otherJob,
+			otherJobTargetURL,
+		),
+		scrapeManager,
+		discoveryManager,
+	)
+
+	// Only the SD target should get dropped for myJob
+	requireTargets(
+		t,
+		scrapeManager,
+		myJob,
+		false,
+		[]string{
+			fmt.Sprintf("http://%s/metrics", myJobStaticTargetURL),
+		},
+	)
+	// The otherJob should keep its target
+	requireTargets(
+		t,
+		scrapeManager,
+		otherJob,
+		false,
+		[]string{fmt.Sprintf("http://%s/metrics", otherJobTargetURL)},
+	)
+}

scrape/scrape.go

@@ -111,6 +111,7 @@ type scrapeLoopOptions struct {
 	interval                 time.Duration
 	timeout                  time.Duration
 	scrapeClassicHistograms  bool
+	validationScheme         model.ValidationScheme
 
 	mrc               []*relabel.Config
 	cache             *scrapeCache
@@ -186,6 +187,7 @@ func newScrapePool(cfg *config.ScrapeConfig, app storage.Appendable, offsetSeed
 			options.PassMetadataInContext,
 			metrics,
 			options.skipOffsetting,
+			opts.validationScheme,
 		)
 	}
 	sp.metrics.targetScrapePoolTargetLimit.WithLabelValues(sp.config.JobName).Set(float64(sp.config.TargetLimit))
@@ -303,6 +305,11 @@ func (sp *scrapePool) restartLoops(reuseCache bool) {
 		mrc                      = sp.config.MetricRelabelConfigs
 	)
 
+	validationScheme := model.LegacyValidation
+	if sp.config.MetricNameValidationScheme == config.UTF8ValidationConfig {
+		validationScheme = model.UTF8Validation
+	}
+
 	sp.targetMtx.Lock()
 
 	forcedErr := sp.refreshTargetLimitErr()
@@ -323,7 +330,7 @@ func (sp *scrapePool) restartLoops(reuseCache bool) {
 				client:               sp.client,
 				timeout:              timeout,
 				bodySizeLimit:        bodySizeLimit,
-				acceptHeader:         acceptHeader(sp.config.ScrapeProtocols),
+				acceptHeader:         acceptHeader(sp.config.ScrapeProtocols, validationScheme),
 				acceptEncodingHeader: acceptEncodingHeader(enableCompression),
 			}
 			newLoop = sp.newLoop(scrapeLoopOptions{
@@ -341,6 +348,7 @@ func (sp *scrapePool) restartLoops(reuseCache bool) {
 				cache:                    cache,
 				interval:                 interval,
 				timeout:                  timeout,
+				validationScheme:         validationScheme,
 			})
 		)
 		if err != nil {
@@ -452,6 +460,11 @@ func (sp *scrapePool) sync(targets []*Target) {
 		scrapeClassicHistograms  = sp.config.ScrapeClassicHistograms
 	)
 
+	validationScheme := model.LegacyValidation
+	if sp.config.MetricNameValidationScheme == config.UTF8ValidationConfig {
+		validationScheme = model.UTF8Validation
+	}
+
 	sp.targetMtx.Lock()
 	for _, t := range targets {
 		hash := t.hash()
@@ -467,7 +480,7 @@ func (sp *scrapePool) sync(targets []*Target) {
 				client:               sp.client,
 				timeout:              timeout,
 				bodySizeLimit:        bodySizeLimit,
-				acceptHeader:         acceptHeader(sp.config.ScrapeProtocols),
+				acceptHeader:         acceptHeader(sp.config.ScrapeProtocols, validationScheme),
 				acceptEncodingHeader: acceptEncodingHeader(enableCompression),
 				metrics:              sp.metrics,
 			}
@@ -714,11 +727,16 @@ var errBodySizeLimit = errors.New("body size limit exceeded")
 // acceptHeader transforms preference from the options into specific header values as
 // https://www.rfc-editor.org/rfc/rfc9110.html#name-accept defines.
 // No validation is here, we expect scrape protocols to be validated already.
-func acceptHeader(sps []config.ScrapeProtocol) string {
+func acceptHeader(sps []config.ScrapeProtocol, scheme model.ValidationScheme) string {
 	var vals []string
 	weight := len(config.ScrapeProtocolsHeaders) + 1
 	for _, sp := range sps {
-		vals = append(vals, fmt.Sprintf("%s;q=0.%d", config.ScrapeProtocolsHeaders[sp], weight))
+		val := config.ScrapeProtocolsHeaders[sp]
+		if scheme == model.UTF8Validation {
+			val += ";" + config.UTF8NamesHeader
+		}
+		val += fmt.Sprintf(";q=0.%d", weight)
+		vals = append(vals, val)
 		weight--
 	}
 	// Default match anything.
@@ -838,6 +856,7 @@ type scrapeLoop struct {
 	interval                 time.Duration
 	timeout                  time.Duration
 	scrapeClassicHistograms  bool
+	validationScheme         model.ValidationScheme
 
 	// Feature flagged options.
 	enableNativeHistogramIngestion bool
@@ -1145,6 +1164,7 @@ func newScrapeLoop(ctx context.Context,
 	passMetadataInContext bool,
 	metrics *scrapeMetrics,
 	skipOffsetting bool,
+	validationScheme model.ValidationScheme,
 ) *scrapeLoop {
 	if l == nil {
 		l = log.NewNopLogger()
@@ -1196,6 +1216,7 @@ func newScrapeLoop(ctx context.Context,
 		appendMetadataToWAL:            appendMetadataToWAL,
 		metrics:                        metrics,
 		skipOffsetting:                 skipOffsetting,
+		validationScheme:               validationScheme,
 	}
 	sl.ctx, sl.cancel = context.WithCancel(ctx)
 
@@ -1616,7 +1637,7 @@ loop:
 				err = errNameLabelMandatory
 				break loop
 			}
-			if !lset.IsValid() {
+			if !lset.IsValid(sl.validationScheme) {
 				err = fmt.Errorf("invalid metric name or label names: %s", lset.String())
 				break loop
 			}
@@ -1631,10 +1652,11 @@ loop:
 			updateMetadata(lset, true)
 		}
 
-		if seriesAlreadyScraped {
+		if seriesAlreadyScraped && parsedTimestamp == nil {
 			err = storage.ErrDuplicateSampleForTimestamp
 		} else {
-			if ctMs := p.CreatedTimestamp(); sl.enableCTZeroIngestion && ctMs != nil {
+			if sl.enableCTZeroIngestion {
+				if ctMs := p.CreatedTimestamp(); ctMs != nil {
 					ref, err = app.AppendCTZeroSample(ref, lset, t, *ctMs)
 					if err != nil && !errors.Is(err, storage.ErrOutOfOrderCT) { // OOO is a common case, ignoring completely for now.
 						// CT is an experimental feature. For now, we don't need to fail the
@@ -1642,6 +1664,7 @@ loop:
 						level.Debug(sl.l).Log("msg", "Error when appending CT in scrape loop", "series", string(met), "ct", *ctMs, "t", t, "err", err)
 					}
 				}
+			}
 
 			if isHistogram && sl.enableNativeHistogramIngestion {
 				if h != nil {

scrape/scrape_test.go

@@ -35,6 +35,7 @@ import (
 	"github.com/gogo/protobuf/proto"
 	"github.com/google/go-cmp/cmp"
 	"github.com/prometheus/client_golang/prometheus"
+	prom_testutil "github.com/prometheus/client_golang/prometheus/testutil"
 	dto "github.com/prometheus/client_model/go"
 	config_util "github.com/prometheus/common/config"
 	"github.com/prometheus/common/model"
@@ -683,6 +684,7 @@ func newBasicScrapeLoop(t testing.TB, ctx context.Context, scraper scraper, app
 		false,
 		newTestScrapeMetrics(t),
 		false,
+		model.LegacyValidation,
 	)
 }
 
@@ -825,6 +827,7 @@ func TestScrapeLoopRun(t *testing.T) {
 		false,
 		scrapeMetrics,
 		false,
+		model.LegacyValidation,
 	)
 
 	// The loop must terminate during the initial offset if the context
@@ -969,6 +972,7 @@ func TestScrapeLoopMetadata(t *testing.T) {
 		false,
 		scrapeMetrics,
 		false,
+		model.LegacyValidation,
 	)
 	defer cancel()
 
@@ -1064,6 +1068,40 @@ func TestScrapeLoopFailWithInvalidLabelsAfterRelabel(t *testing.T) {
 	require.Equal(t, 0, seriesAdded)
 }
 
+func TestScrapeLoopFailLegacyUnderUTF8(t *testing.T) {
+	// Test that scrapes fail when default validation is utf8 but scrape config is
+	// legacy.
+	model.NameValidationScheme = model.UTF8Validation
+	defer func() {
+		model.NameValidationScheme = model.LegacyValidation
+	}()
+	s := teststorage.New(t)
+	defer s.Close()
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	sl := newBasicScrapeLoop(t, ctx, &testScraper{}, s.Appender, 0)
+	sl.validationScheme = model.LegacyValidation
+
+	slApp := sl.appender(ctx)
+	total, added, seriesAdded, err := sl.append(slApp, []byte("{\"test.metric\"} 1\n"), "", time.Time{})
+	require.ErrorContains(t, err, "invalid metric name or label names")
+	require.NoError(t, slApp.Rollback())
+	require.Equal(t, 1, total)
+	require.Equal(t, 0, added)
+	require.Equal(t, 0, seriesAdded)
+
+	// When scrapeloop has validation set to UTF-8, the metric is allowed.
+	sl.validationScheme = model.UTF8Validation
+
+	slApp = sl.appender(ctx)
+	total, added, seriesAdded, err = sl.append(slApp, []byte("{\"test.metric\"} 1\n"), "", time.Time{})
+	require.NoError(t, err)
+	require.Equal(t, 1, total)
+	require.Equal(t, 1, added)
+	require.Equal(t, 1, seriesAdded)
+}
+
 func makeTestMetrics(n int) []byte {
 	// Construct a metrics string to parse
 	sb := bytes.Buffer{}
@@ -2339,11 +2377,15 @@ func TestTargetScraperScrapeOK(t *testing.T) {
 	)
 
 	var protobufParsing bool
+	var allowUTF8 bool
 
 	server := httptest.NewServer(
 		http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			if protobufParsing {
 			accept := r.Header.Get("Accept")
+			if allowUTF8 {
+				require.Truef(t, strings.Contains(accept, "escaping=allow-utf-8"), "Expected Accept header to allow utf8, got %q", accept)
+			}
+			if protobufParsing {
 				require.True(t, strings.HasPrefix(accept, "application/vnd.google.protobuf;"),
 					"Expected Accept header to prefer application/vnd.google.protobuf.")
 			}
@@ -2351,7 +2393,11 @@ func TestTargetScraperScrapeOK(t *testing.T) {
 			timeout := r.Header.Get("X-Prometheus-Scrape-Timeout-Seconds")
 			require.Equal(t, expectedTimeout, timeout, "Expected scrape timeout header.")
 
+			if allowUTF8 {
+				w.Header().Set("Content-Type", `text/plain; version=1.0.0; escaping=allow-utf-8`)
+			} else {
 				w.Header().Set("Content-Type", `text/plain; version=0.0.4`)
+			}
 			w.Write([]byte("metric_a 1\nmetric_b 2\n"))
 		}),
 	)
@@ -2380,13 +2426,22 @@ func TestTargetScraperScrapeOK(t *testing.T) {
 		require.NoError(t, err)
 		contentType, err := ts.readResponse(context.Background(), resp, &buf)
 		require.NoError(t, err)
+		if allowUTF8 {
+			require.Equal(t, "text/plain; version=1.0.0; escaping=allow-utf-8", contentType)
+		} else {
 			require.Equal(t, "text/plain; version=0.0.4", contentType)
+		}
 		require.Equal(t, "metric_a 1\nmetric_b 2\n", buf.String())
 	}
 
-	runTest(acceptHeader(config.DefaultScrapeProtocols))
+	runTest(acceptHeader(config.DefaultScrapeProtocols, model.LegacyValidation))
 	protobufParsing = true
-	runTest(acceptHeader(config.DefaultProtoFirstScrapeProtocols))
+	runTest(acceptHeader(config.DefaultProtoFirstScrapeProtocols, model.LegacyValidation))
+	protobufParsing = false
+	allowUTF8 = true
+	runTest(acceptHeader(config.DefaultScrapeProtocols, model.UTF8Validation))
+	protobufParsing = true
+	runTest(acceptHeader(config.DefaultProtoFirstScrapeProtocols, model.UTF8Validation))
 }
 
 func TestTargetScrapeScrapeCancel(t *testing.T) {
@@ -2412,7 +2467,7 @@ func TestTargetScrapeScrapeCancel(t *testing.T) {
 			),
 		},
 		client:       http.DefaultClient,
-		acceptHeader: acceptHeader(config.DefaultGlobalConfig.ScrapeProtocols),
+		acceptHeader: acceptHeader(config.DefaultGlobalConfig.ScrapeProtocols, model.LegacyValidation),
 	}
 	ctx, cancel := context.WithCancel(context.Background())
 
@@ -2467,7 +2522,7 @@ func TestTargetScrapeScrapeNotFound(t *testing.T) {
 			),
 		},
 		client:       http.DefaultClient,
-		acceptHeader: acceptHeader(config.DefaultGlobalConfig.ScrapeProtocols),
+		acceptHeader: acceptHeader(config.DefaultGlobalConfig.ScrapeProtocols, model.LegacyValidation),
 	}
 
 	resp, err := ts.scrape(context.Background())
@@ -2511,7 +2566,7 @@ func TestTargetScraperBodySizeLimit(t *testing.T) {
 		},
 		client:        http.DefaultClient,
 		bodySizeLimit: bodySizeLimit,
-		acceptHeader:  acceptHeader(config.DefaultGlobalConfig.ScrapeProtocols),
+		acceptHeader:  acceptHeader(config.DefaultGlobalConfig.ScrapeProtocols, model.LegacyValidation),
 		metrics:       newTestScrapeMetrics(t),
 	}
 	var buf bytes.Buffer
@@ -3627,6 +3682,7 @@ func TestScrapeLoopSeriesAddedDuplicates(t *testing.T) {
 	require.Equal(t, 3, total)
 	require.Equal(t, 3, added)
 	require.Equal(t, 1, seriesAdded)
+	require.Equal(t, 2.0, prom_testutil.ToFloat64(sl.metrics.targetScrapeSampleDuplicate))
 
 	slApp = sl.appender(ctx)
 	total, added, seriesAdded, err = sl.append(slApp, []byte("test_metric 1\ntest_metric 1\ntest_metric 1\n"), "", time.Time{})
@@ -3635,12 +3691,18 @@ func TestScrapeLoopSeriesAddedDuplicates(t *testing.T) {
 	require.Equal(t, 3, total)
 	require.Equal(t, 3, added)
 	require.Equal(t, 0, seriesAdded)
+	require.Equal(t, 4.0, prom_testutil.ToFloat64(sl.metrics.targetScrapeSampleDuplicate))
 
-	metric := dto.Metric{}
+	// When different timestamps are supplied, multiple samples are accepted.
-	err = sl.metrics.targetScrapeSampleDuplicate.Write(&metric)
+	slApp = sl.appender(ctx)
+	total, added, seriesAdded, err = sl.append(slApp, []byte("test_metric 1 1001\ntest_metric 1 1002\ntest_metric 1 1003\n"), "", time.Time{})
 	require.NoError(t, err)
-	value := metric.GetCounter().GetValue()
+	require.NoError(t, slApp.Commit())
-	require.Equal(t, 4.0, value)
+	require.Equal(t, 3, total)
+	require.Equal(t, 3, added)
+	require.Equal(t, 0, seriesAdded)
+	// Metric is not higher than last time.
+	require.Equal(t, 4.0, prom_testutil.ToFloat64(sl.metrics.targetScrapeSampleDuplicate))
 }
 
 // This tests running a full scrape loop and checking that the scrape option

scrape/testdata/ca.cer

@@ -1,8 +1,66 @@
+Certificate:
+    Data:
+        Version: 3 (0x2)
+        Serial Number:
+            93:6c:9e:29:8d:37:7b:66
+        Signature Algorithm: sha256WithRSAEncryption
+        Issuer: C = XX, L = Default City, O = Default Company Ltd, CN = Prometheus Test CA
+        Validity
+            Not Before: Aug 20 11:51:23 2024 GMT
+            Not After : Dec  5 11:51:23 2044 GMT
+        Subject: C = XX, L = Default City, O = Default Company Ltd, CN = Prometheus Test CA
+        Subject Public Key Info:
+            Public Key Algorithm: rsaEncryption
+                Public-Key: (2048 bit)
+                Modulus:
+                    00:e9:52:05:4d:f2:5a:95:04:2d:b8:73:8b:3c:e7:
+                    47:48:67:00:be:dd:6c:41:f3:7c:4b:44:73:a3:77:
+                    3e:84:af:30:d7:2a:ad:45:6a:b7:89:23:05:15:b3:
+                    aa:46:79:b8:95:64:cc:13:c4:44:a1:01:a0:e2:3d:
+                    a5:67:2b:aa:d3:13:06:43:33:1c:96:36:12:9e:c6:
+                    1d:36:9b:d7:47:bd:28:2d:88:15:04:fa:14:a3:ff:
+                    8c:26:22:c5:a2:15:c7:76:b3:11:f6:a3:44:9a:28:
+                    0f:ca:fb:f4:51:a8:6a:05:94:7c:77:47:c8:21:56:
+                    25:bf:e2:2e:df:33:f3:e4:bd:d6:47:a5:49:13:12:
+                    c8:1f:4c:d7:2a:56:a2:6c:c1:cf:55:05:5d:9a:75:
+                    a2:23:4e:e6:8e:ff:76:05:d6:e0:c8:0b:51:f0:b6:
+                    a1:b2:7d:8f:9c:6a:a5:ce:86:92:15:8c:5b:86:45:
+                    c0:4a:ff:54:b8:ee:cf:11:bd:07:cb:4b:7d:0b:a1:
+                    9d:72:86:9f:55:bc:f9:6c:d9:55:60:96:30:3f:ec:
+                    2d:f6:5f:9a:32:9a:5a:5c:1c:5f:32:f9:d6:0f:04:
+                    f8:81:08:04:9a:95:c3:9d:5a:30:8e:a5:0e:47:2f:
+                    00:ce:e0:2e:ad:5a:b8:b6:4c:55:7c:8a:59:22:b0:
+                    ed:73
+                Exponent: 65537 (0x10001)
+        X509v3 extensions:
+            X509v3 Subject Key Identifier: 
+                CC:F5:05:99:E5:AB:12:69:D8:78:89:4A:31:CA:F0:8B:0B:AD:66:1B
+            X509v3 Authority Key Identifier: 
+                CC:F5:05:99:E5:AB:12:69:D8:78:89:4A:31:CA:F0:8B:0B:AD:66:1B
+            X509v3 Basic Constraints: 
+                CA:TRUE
+    Signature Algorithm: sha256WithRSAEncryption
+    Signature Value:
+        4a:a1:b0:bc:c8:87:4f:7c:96:62:e5:09:29:ae:3a:2e:68:d0:
+        d2:c5:68:ed:ea:83:36:b1:86:f3:b9:e9:19:2b:b6:73:10:6f:
+        df:7f:bb:f1:76:81:03:c1:a1:5a:ee:6c:44:b8:7c:10:d1:5a:
+        d7:c1:92:64:59:35:a6:e0:aa:08:41:37:6e:e7:c8:b6:bd:0c:
+        4b:47:78:ec:c4:b4:15:a3:62:76:4a:39:8e:6e:19:ff:f0:c0:
+        8a:7e:1c:cd:87:e5:00:6c:f1:ce:27:26:ff:b8:e9:eb:f7:2f:
+        bd:c2:4b:9c:d6:57:de:74:74:b3:4f:03:98:9a:b5:08:2d:16:
+        ca:7f:b6:c8:76:62:86:1b:7c:f2:3e:6c:78:cc:2c:95:9a:bb:
+        77:25:e8:80:ff:9b:e8:f8:9a:85:3b:85:b7:17:4e:77:a1:cf:
+        4d:b9:d0:25:e8:5d:8c:e6:7c:f1:d9:52:30:3d:ec:2b:37:91:
+        bc:e2:e8:39:31:6f:3d:e9:98:70:80:7c:41:dd:19:13:05:21:
+        94:7b:16:cf:d8:ee:4e:38:34:5e:6a:ff:cd:85:ac:8f:94:9a:
+        dd:4e:77:05:13:a6:b4:80:52:b2:97:64:76:88:f4:dd:42:0a:
+        50:1c:80:fd:4b:6e:a9:62:10:aa:ef:2e:c1:2f:be:0e:c2:2e:
+        b5:28:5f:83
 -----BEGIN CERTIFICATE-----
 MIIDkTCCAnmgAwIBAgIJAJNsnimNN3tmMA0GCSqGSIb3DQEBCwUAMF8xCzAJBgNV
 BAYTAlhYMRUwEwYDVQQHDAxEZWZhdWx0IENpdHkxHDAaBgNVBAoME0RlZmF1bHQg
-Q29tcGFueSBMdGQxGzAZBgNVBAMMElByb21ldGhldXMgVGVzdCBDQTAeFw0xNTA4
+Q29tcGFueSBMdGQxGzAZBgNVBAMMElByb21ldGhldXMgVGVzdCBDQTAeFw0yNDA4
-MDQxNDA5MjFaFw0yNTA4MDExNDA5MjFaMF8xCzAJBgNVBAYTAlhYMRUwEwYDVQQH
+MjAxMTUxMjNaFw00NDEyMDUxMTUxMjNaMF8xCzAJBgNVBAYTAlhYMRUwEwYDVQQH
 DAxEZWZhdWx0IENpdHkxHDAaBgNVBAoME0RlZmF1bHQgQ29tcGFueSBMdGQxGzAZ
 BgNVBAMMElByb21ldGhldXMgVGVzdCBDQTCCASIwDQYJKoZIhvcNAQEBBQADggEP
 ADCCAQoCggEBAOlSBU3yWpUELbhzizznR0hnAL7dbEHzfEtEc6N3PoSvMNcqrUVq
@@ -12,11 +70,11 @@ yB9M1ypWomzBz1UFXZp1oiNO5o7/dgXW4MgLUfC2obJ9j5xqpc6GkhWMW4ZFwEr/
 VLjuzxG9B8tLfQuhnXKGn1W8+WzZVWCWMD/sLfZfmjKaWlwcXzL51g8E+IEIBJqV
 w51aMI6lDkcvAM7gLq1auLZMVXyKWSKw7XMCAwEAAaNQME4wHQYDVR0OBBYEFMz1
 BZnlqxJp2HiJSjHK8IsLrWYbMB8GA1UdIwQYMBaAFMz1BZnlqxJp2HiJSjHK8IsL
-rWYbMAwGA1UdEwQFMAMBAf8wDQYJKoZIhvcNAQELBQADggEBAI2iA3w3TK5J15Pu
+rWYbMAwGA1UdEwQFMAMBAf8wDQYJKoZIhvcNAQELBQADggEBAEqhsLzIh098lmLl
-e4fPFB4jxQqsbUwuyXbCCv/jKLeFNCD4BjM181WZEYjPMumeTBVzU3aF45LWQIG1
+CSmuOi5o0NLFaO3qgzaxhvO56RkrtnMQb99/u/F2gQPBoVrubES4fBDRWtfBkmRZ
-0DJcrCL4mjMz9qgAoGqA7aDDXiJGbukMgYYsn7vrnVmrZH8T3E8ySlltr7+W578k
+NabgqghBN27nyLa9DEtHeOzEtBWjYnZKOY5uGf/wwIp+HM2H5QBs8c4nJv+46ev3
-pJ5FxnbCroQwn0zLyVB3sFbS8E3vpBr3L8oy8PwPHhIScexcNVc3V6/m4vTZsXTH
+L73CS5zWV950dLNPA5iatQgtFsp/tsh2YoYbfPI+bHjMLJWau3cl6ID/m+j4moU7
-U+vUm1XhDgpDcFMTg2QQiJbfpOYUkwIgnRDAT7t282t2KQWtnlqc3zwPQ1F/6Cpx
+hbcXTnehz0250CXoXYzmfPHZUjA97Cs3kbzi6Dkxbz3pmHCAfEHdGRMFIZR7Fs/Y
-j19JeNsaF1DArkD7YlyKj/GhZLtHwFHG5cxznH0mLDJTW7bQvqqh2iQTeXmBk1lU
+7k44NF5q/82FrI+Umt1OdwUTprSAUrKXZHaI9N1CClAcgP1LbqliEKrvLsEvvg7C
-mM5lH/s=
+LrUoX4M=
 -----END CERTIFICATE-----

scripts/golangci-lint.yml

@@ -26,14 +26,14 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
       - name: Install Go
-        uses: actions/setup-go@cdcb36043654635271a94b9a6d1392de5bb323a7 # v5.0.1
+        uses: actions/setup-go@0a12ed9d6a96ab950c8f026ed9f722fe0da7ef32 # v5.0.2
         with:
           go-version: 1.22.x
       - name: Install snmp_exporter/generator dependencies
         run: sudo apt-get update && sudo apt-get -y install libsnmp-dev
         if: github.repository == 'prometheus/snmp_exporter'
       - name: Lint
-        uses: golangci/golangci-lint-action@a4f60bb28d35aeee14e6880718e0c85ff1882e64 # v6.0.1
+        uses: golangci/golangci-lint-action@aaa42aa0628b4ae2578232a66b541047968fac86 # v6.1.0
         with:
           args: --verbose
-          version: v1.59.1
+          version: v1.60.2

scripts/sync_repo_files.sh

@@ -37,7 +37,7 @@ if [ -z "${GITHUB_TOKEN}" ]; then
 fi
 
 # List of files that should be synced.
-SYNC_FILES="CODE_OF_CONDUCT.md LICENSE Makefile.common SECURITY.md .yamllint scripts/golangci-lint.yml .github/workflows/scorecards.yml .github/workflows/container_description.yml"
+SYNC_FILES="CODE_OF_CONDUCT.md LICENSE Makefile.common SECURITY.md .yamllint scripts/golangci-lint.yml .github/workflows/scorecards.yml .github/workflows/container_description.yml .github/workflows/stale.yml"
 
 # Go to the root of the repo
 cd "$(git rev-parse --show-cdup)" || exit 1

storage/buffer_test.go

@@ -96,10 +96,10 @@ func TestSampleRingMixed(t *testing.T) {
 
 	// With ValNone as the preferred type, nothing should be initialized.
 	r := newSampleRing(10, 2, chunkenc.ValNone)
-	require.Zero(t, len(r.fBuf))
+	require.Empty(t, r.fBuf)
-	require.Zero(t, len(r.hBuf))
+	require.Empty(t, r.hBuf)
-	require.Zero(t, len(r.fhBuf))
+	require.Empty(t, r.fhBuf)
-	require.Zero(t, len(r.iBuf))
+	require.Empty(t, r.iBuf)
 
 	// But then mixed adds should work as expected.
 	r.addF(fSample{t: 1, f: 3.14})
@@ -146,10 +146,10 @@ func TestSampleRingAtFloatHistogram(t *testing.T) {
 
 	// With ValNone as the preferred type, nothing should be initialized.
 	r := newSampleRing(10, 2, chunkenc.ValNone)
-	require.Zero(t, len(r.fBuf))
+	require.Empty(t, r.fBuf)
-	require.Zero(t, len(r.hBuf))
+	require.Empty(t, r.hBuf)
-	require.Zero(t, len(r.fhBuf))
+	require.Empty(t, r.fhBuf)
-	require.Zero(t, len(r.iBuf))
+	require.Empty(t, r.iBuf)
 
 	var (
 		h  *histogram.Histogram

storage/errors.go

@@ -18,6 +18,7 @@ import "fmt"
 type errDuplicateSampleForTimestamp struct {
 	timestamp           int64
 	existing            float64
+	existingIsHistogram bool
 	newValue            float64
 }
 
@@ -29,13 +30,26 @@ func NewDuplicateFloatErr(t int64, existing, newValue float64) error {
 	}
 }
 
+// NewDuplicateHistogramToFloatErr describes an error where a new float sample is sent for same timestamp as previous histogram.
+func NewDuplicateHistogramToFloatErr(t int64, newValue float64) error {
+	return errDuplicateSampleForTimestamp{
+		timestamp:           t,
+		existingIsHistogram: true,
+		newValue:            newValue,
+	}
+}
+
 func (e errDuplicateSampleForTimestamp) Error() string {
 	if e.timestamp == 0 {
 		return "duplicate sample for timestamp"
 	}
+	if e.existingIsHistogram {
+		return fmt.Sprintf("duplicate sample for timestamp %d; overrides not allowed: existing is a histogram, new value %g", e.timestamp, e.newValue)
+	}
 	return fmt.Sprintf("duplicate sample for timestamp %d; overrides not allowed: existing %g, new value %g", e.timestamp, e.existing, e.newValue)
 }
 
+// Is implements the anonymous interface checked by errors.Is.
 // Every errDuplicateSampleForTimestamp compares equal to the global ErrDuplicateSampleForTimestamp.
 func (e errDuplicateSampleForTimestamp) Is(t error) bool {
 	if t == ErrDuplicateSampleForTimestamp {

storage/errors_test.go

@@ -0,0 +1,38 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package storage
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestErrDuplicateSampleForTimestamp(t *testing.T) {
+	// All errDuplicateSampleForTimestamp are ErrDuplicateSampleForTimestamp
+	require.ErrorIs(t, ErrDuplicateSampleForTimestamp, errDuplicateSampleForTimestamp{})
+
+	// Same type only is if it has same properties.
+	err := NewDuplicateFloatErr(1_000, 10, 20)
+	sameErr := NewDuplicateFloatErr(1_000, 10, 20)
+	differentErr := NewDuplicateFloatErr(1_001, 30, 40)
+
+	require.ErrorIs(t, err, sameErr)
+	require.NotErrorIs(t, err, differentErr)
+
+	// Also works when err is wrapped.
+	require.ErrorIs(t, fmt.Errorf("failed: %w", err), sameErr)
+	require.NotErrorIs(t, fmt.Errorf("failed: %w", err), differentErr)
+}