prometheus/CHANGELOG.md

0.18.0 / 2016-04-18

• [BUGFIX] Fix operator precedence in PromQL
• [BUGFIX] Never drop still open head chunk
• [BUGFIX] Fix missing 'keep_common' when printing AST node
• [CHANGE/BUGFIX] Target identity considers path and parameters additionally to host and port
• [CHANGE] Rename metric prometheus_local_storage_invalid_preload_requests_total to prometheus_local_storage_non_existent_series_matches_total
• [CHANGE] Support for old alerting rule syntax dropped
• [FEATURE] Deduplicate targets within the same scrape job
• [FEATURE] Add varbit chunk encoding (higher compression, more CPU usage – disabled by default)
• [FEATURE] Add holt_winters query function
• [FEATURE] Add relative complement unless operator to PromQL
• [ENHANCEMENT] Quarantine series file if data corruption is encountered (instead of crashing)
• [ENHANCEMENT] Validate Alertmanager URL
• [ENHANCEMENT] Use UTC for build timestamp
• [ENHANCEMENT] Improve index query performance (especially for active time series)
• [ENHANCEMENT] Instrument configuration reload duration
• [ENHANCEMENT] Instrument retrieval layer
• [ENHANCEMENT] Add Go version to prometheus_build_info metric

0.17.0 / 2016-03-02

This version no longer works with Alertmanager 0.0.4 and earlier! The alerting rule syntax has changed as well but the old syntax is supported up until version 0.18.

All regular expressions in PromQL are anchored now, matching the behavior of regular expressions in config files.

• [CHANGE] Integrate with Alertmanager 0.1.0 and higher
• [CHANGE] Degraded storage mode renamed to rushed mode
• [CHANGE] New alerting rule syntax
• [CHANGE] Add label validation on ingestion
• [CHANGE] Regular expression matchers in PromQL are anchored
• [FEATURE] Add without aggregation modifier
• [FEATURE] Send alert resolved notifications to Alertmanager
• [FEATURE] Allow millisecond precision in configuration file
• [FEATURE] Support AirBnB's Smartstack Nerve for service discovery
• [ENHANCEMENT] Storage switches less often between regular and rushed mode.
• [ENHANCEMENT] Storage switches into rushed mode if there are too many memory chunks.
• [ENHANCEMENT] Added more storage instrumentation
• [ENHANCEMENT] Improved instrumentation of notification handler
• [BUGFIX] Do not count head chunks as chunks waiting for persistence
• [BUGFIX] Handle OPTIONS HTTP requests to the API correctly
• [BUGFIX] Parsing of ranges in PromQL fixed
• [BUGFIX] Correctly validate URL flag parameters
• [BUGFIX] Log argument parse errors
• [BUGFIX] Properly handle creation of target with bad TLS config
• [BUGFIX] Fix of checkpoint timing issue

0.16.2 / 2016-01-18

• [FEATURE] Multiple authentication options for EC2 discovery added
• [FEATURE] Several meta labels for EC2 discovery added
• [FEATURE] Allow full URLs in static target groups (used e.g. by the blackbox_exporter)
• [FEATURE] Add Graphite remote-storage integration
• [FEATURE] Create separate Kubernetes targets for services and their endpoints
• [FEATURE] Add clamp_{min,max} functions to PromQL
• [FEATURE] Omitted time parameter in API query defaults to now
• [ENHANCEMENT] Less frequent time series file truncation
• [ENHANCEMENT] Instrument number of manually deleted time series
• [ENHANCEMENT] Ignore lost+found directory during storage version detection
• [CHANGE] Kubernetes masters renamed to api_servers
• [CHANGE] "Healthy" and "unhealthy" targets are now called "up" and "down" in the web UI
• [CHANGE] Remove undocumented 2nd argument of the delta function. (This is a BREAKING CHANGE for users of the undocumented 2nd argument.)
• [BUGFIX] Return proper HTTP status codes on API errors
• [BUGFIX] Fix Kubernetes authentication configuration
• [BUGFIX] Fix stripped OFFSET from in rule evaluation and display
• [BUGFIX] Do not crash on failing Consul SD initialization
• [BUGFIX] Revert changes to metric auto-completion
• [BUGFIX] Add config overflow validation for TLS configuration
• [BUGFIX] Skip already watched Zookeeper nodes in serverset SD
• [BUGFIX] Don't federate stale samples
• [BUGFIX] Move NaN to end of result for topk/bottomk/sort/sort_desc/min/max
• [BUGFIX] Limit extrapolation of delta/rate/increase
• [BUGFIX] Fix unhandled error in rule evaluation

Some changes to the Kubernetes service discovery were integration since it was released as a beta feature.

0.16.1 / 2015-10-16

• [FEATURE] Add irate() function.
• [ENHANCEMENT] Improved auto-completion in expression browser.
• [CHANGE] Kubernetes SD moves node label to instance label.
• [BUGFIX] Escape regexes in console templates.

0.16.0 / 2015-10-09

BREAKING CHANGES:

• Release tarballs now contain the built binaries in a nested directory.
• The hash_mod relabeling action now uses MD5 hashes instead of FNV hashes to achieve a better distribution.
• The DNS-SD meta label __meta_dns_srv_name was renamed to __meta_dns_name to reflect support for DNS record types other than SRV.
• The default full refresh interval for the file-based service discovery has been increased from 30 seconds to 5 minutes.
• In relabeling, parts of a source label that weren't matched by the specified regular expression are no longer included in the replacement output.
• Queries no longer interpolate between two data points. Instead, the resulting value will always be the latest value before the evaluation query timestamp.
• Regular expressions supplied via the configuration are now anchored to match full strings instead of substrings.
• Global labels are not appended upon storing time series anymore. Instead, they are only appended when communicating with external systems (Alertmanager, remote storages, federation). They have thus also been renamed from global.labels to global.external_labels.
• The names and units of metrics related to remote storage sample appends have been changed.
• The experimental support for writing to InfluxDB has been updated to work with InfluxDB 0.9.x. 0.8.x versions of InfluxDB are not supported anymore.
• Escape sequences in double- and single-quoted string literals in rules or query expressions are now interpreted like escape sequences in Go string literals (https://golang.org/ref/spec#String_literals).

Future breaking changes / deprecated features:

• The delta() function had an undocumented optional second boolean argument to make it behave like increase(). This second argument will be removed in the future. Migrate any occurrences of delta(x, 1) to use increase(x) instead.
• Support for filter operators between two scalar values (like 2 > 1) will be removed in the future. These will require a bool modifier on the operator, e.g. 2 > bool 1.

All changes:

• [CHANGE] Renamed global.labels to global.external_labels.
• [CHANGE] Vendoring is now done via govendor instead of godep.
• [CHANGE] Change web UI root page to show the graphing interface instead of the server status page.
• [CHANGE] Append global labels only when communicating with external systems instead of storing them locally.
• [CHANGE] Change all regexes in the configuration to do full-string matches instead of substring matches.
• [CHANGE] Remove interpolation of vector values in queries.
• [CHANGE] For alert SUMMARY/DESCRIPTION template fields, cast the alert value to float64 to work with common templating functions.
• [CHANGE] In relabeling, don't include unmatched source label parts in the replacement.
• [CHANGE] Change default full refresh interval for the file-based service discovery from 30 seconds to 5 minutes.
• [CHANGE] Rename the DNS-SD meta label __meta_dns_srv_name to __meta_dns_name to reflect support for other record types than SRV.
• [CHANGE] Release tarballs now contain the binaries in a nested directory.
• [CHANGE] Update InfluxDB write support to work with InfluxDB 0.9.x.
• [FEATURE] Support full "Go-style" escape sequences in strings and add raw string literals.
• [FEATURE] Add EC2 service discovery support.
• [FEATURE] Allow configuring TLS options in scrape configurations.
• [FEATURE] Add instrumentation around configuration reloads.
• [FEATURE] Add bool modifier to comparison operators to enable boolean (0/1) output instead of filtering.
• [FEATURE] In Zookeeper serverset discovery, provide __meta_serverset_shard label with the serverset shard number.
• [FEATURE] Provide __meta_consul_service_id meta label in Consul service discovery.
• [FEATURE] Allow scalar expressions in recording rules to enable use cases such as building constant metrics.
• [FEATURE] Add label_replace() and vector() query language functions.
• [FEATURE] In Consul service discovery, fill in the __meta_consul_dc datacenter label from the Consul agent when it's not set in the Consul SD config.
• [FEATURE] Scrape all services upon empty services list in Consul service discovery.
• [FEATURE] Add labelmap relabeling action to map a set of input labels to a set of output labels using regular expressions.
• [FEATURE] Introduce __tmp as a relabeling label prefix that is guaranteed to not be used by Prometheus internally.
• [FEATURE] Kubernetes-based service discovery.
• [FEATURE] Marathon-based service discovery.
• [FEATURE] Support multiple series names in console graphs JavaScript library.
• [FEATURE] Allow reloading configuration via web handler at /-/reload.
• [FEATURE] Updates to promtool to reflect new Prometheus configuration features.
• [FEATURE] Add proxy_url parameter to scrape configurations to enable use of proxy servers.
• [FEATURE] Add console templates for Prometheus itself.
• [FEATURE] Allow relabeling the protocol scheme of targets.
• [FEATURE] Add predict_linear() query language function.
• [FEATURE] Support for authentication using bearer tokens, client certs, and CA certs.
• [FEATURE] Implement unary expressions for vector types (-foo, +foo).
• [FEATURE] Add console templates for the SNMP exporter.
• [FEATURE] Make it possible to relabel target scrape query parameters.
• [FEATURE] Add support for A and AAAA records in DNS service discovery.
• [ENHANCEMENT] Fix several flaky tests.
• [ENHANCEMENT] Switch to common routing package.
• [ENHANCEMENT] Use more resilient metric decoder.
• [ENHANCEMENT] Update vendored dependencies.
• [ENHANCEMENT] Add compression to more HTTP handlers.
• [ENHANCEMENT] Make -web.external-url flag help string more verbose.
• [ENHANCEMENT] Improve metrics around remote storage queues.
• [ENHANCEMENT] Use Go 1.5.1 instead of Go 1.4.2 in builds.
• [ENHANCEMENT] Update the architecture diagram in the README.md.
• [ENHANCEMENT] Time out sample appends in retrieval layer if the storage is backlogging.
• [ENHANCEMENT] Make hash_mod relabeling action use MD5 instead of FNV to enable better hash distribution.
• [ENHANCEMENT] Better tracking of targets between same service discovery mechanisms in one scrape configuration.
• [ENHANCEMENT] Handle parser and query evaluation runtime panics more gracefully.
• [ENHANCEMENT] Add IDs to H2 tags on status page to allow anchored linking.
• [BUGFIX] Fix watching multiple paths with Zookeeper serverset discovery.
• [BUGFIX] Fix high CPU usage on configuration reload.
• [BUGFIX] Fix disappearing __params on configuration reload.
• [BUGFIX] Make labelmap action available through configuration.
• [BUGFIX] Fix direct access of protobuf fields.
• [BUGFIX] Fix panic on Consul request error.
• [BUGFIX] Redirect of graph endpoint for prefixed setups.
• [BUGFIX] Fix series file deletion behavior when purging archived series.
• [BUGFIX] Fix error checking and logging around checkpointing.
• [BUGFIX] Fix map initialization in target manager.
• [BUGFIX] Fix draining of file watcher events in file-based service discovery.
• [BUGFIX] Add POST handler for /debug endpoints to fix CPU profiling.
• [BUGFIX] Fix several flaky tests.
• [BUGFIX] Fix busylooping in case a scrape configuration has no target providers defined.
• [BUGFIX] Fix exit behavior of static target provider.
• [BUGFIX] Fix configuration reloading loop upon shutdown.
• [BUGFIX] Add missing check for nil expression in expression parser.
• [BUGFIX] Fix error handling bug in test code.
• [BUGFIX] Fix Consul port meta label.
• [BUGFIX] Fix lexer bug that treated non-Latin Unicode digits as digits.
• [CLEANUP] Remove obsolete federation example from console templates.
• [CLEANUP] Remove duplicated Bootstrap JS inclusion on graph page.
• [CLEANUP] Switch to common log package.
• [CLEANUP] Update build environment scripts and Makefiles to work better with native Go build mechanisms and new Go 1.5 experimental vendoring support.
• [CLEANUP] Remove logged notice about 0.14.x configuration file format change.
• [CLEANUP] Move scrape-time metric label modification into SampleAppenders.
• [CLEANUP] Switch from github.com/client_golang/model to github.com/common/model and related type cleanups.
• [CLEANUP] Switch from github.com/client_golang/extraction to github.com/common/expfmt and related type cleanups.
• [CLEANUP] Exit Prometheus when the web server encounters a startup error.
• [CLEANUP] Remove non-functional alert-silencing links on alerting page.
• [CLEANUP] General cleanups to comments and code, derived from golint, go vet, or otherwise.
• [CLEANUP] When entering crash recovery, tell users how to cleanly shut down Prometheus.
• [CLEANUP] Remove internal support for multi-statement queries in query engine.
• [CLEANUP] Update AUTHORS.md.
• [CLEANUP] Don't warn/increment metric upon encountering equal timestamps for the same series upon append.
• [CLEANUP] Resolve relative paths during configuration loading.

0.15.1 / 2015-07-27

• [BUGFIX] Fix vector matching behavior when there is a mix of equality and non-equality matchers in a vector selector and one matcher matches no series.
• [ENHANCEMENT] Allow overriding GOARCH and GOOS in Makefile.INCLUDE.
• [ENHANCEMENT] Update vendored dependencies.

0.15.0 / 2015-07-21

BREAKING CHANGES:

• Relative paths for rule files are now evaluated relative to the config file.
• External reachability flags (-web.*) consolidated.
• The default storage directory has been changed from /tmp/metrics to data in the local directory.
• The rule_checker tool has been replaced by promtool with different flags and more functionality.
• Empty labels are now removed upon ingestion into the storage. Matching empty labels is now equivalent to matching unset labels (mymetric{label=""} now matches series that don't have label set at all).
• The special __meta_consul_tags label in Consul service discovery now starts and ends with tag separators to enable easier regex matching.
• The default scrape interval has been changed back from 1 minute to 10 seconds.

All changes:

• [CHANGE] Change default storage directory to data in the current working directory.
• [CHANGE] Consolidate external reachability flags (-web.*)into one.
• [CHANGE] Deprecate keeping_extra modifier keyword, rename it to keep_common.
• [CHANGE] Improve label matching performance and treat unset labels like empty labels in label matchers.
• [CHANGE] Remove rule_checker tool and add generic promtool CLI tool which allows checking rules and configuration files.
• [CHANGE] Resolve rule files relative to config file.
• [CHANGE] Restore default ScrapeInterval of 1 minute instead of 10 seconds.
• [CHANGE] Surround __meta_consul_tags value with tag separators.
• [CHANGE] Update node disk console for new filesystem labels.
• [FEATURE] Add Consul's ServiceAddress, Address, and ServicePort as meta labels to enable setting a custom scrape address if needed.
• [FEATURE] Add hashmod relabel action to allow for horizontal sharding of Prometheus servers.
• [FEATURE] Add honor_labels scrape configuration option to not overwrite any labels exposed by the target.
• [FEATURE] Add basic federation support on /federate.
• [FEATURE] Add optional RUNBOOK field to alert statements.
• [FEATURE] Add pre-relabel target labels to status page.
• [FEATURE] Add version information endpoint under /version.
• [FEATURE] Added initial stable API version 1 under /api/v1, including ability to delete series and query more metadata.
• [FEATURE] Allow configuring query parameters when scraping metrics endpoints.
• [FEATURE] Allow deleting time series via the new v1 API.
• [FEATURE] Allow individual ingested metrics to be relabeled.
• [FEATURE] Allow loading rule files from an entire directory.
• [FEATURE] Allow scalar expressions in range queries, improve error messages.
• [FEATURE] Support Zookeeper Serversets as a service discovery mechanism.
• [ENHANCEMENT] Add circleci yaml for Dockerfile test build.
• [ENHANCEMENT] Always show selected graph range, regardless of available data.
• [ENHANCEMENT] Change expression input field to multi-line textarea.
• [ENHANCEMENT] Enforce strict monotonicity of time stamps within a series.
• [ENHANCEMENT] Export build information as metric.
• [ENHANCEMENT] Improve UI of /alerts page.
• [ENHANCEMENT] Improve display of target labels on status page.
• [ENHANCEMENT] Improve initialization and routing functionality of web service.
• [ENHANCEMENT] Improve target URL handling and display.
• [ENHANCEMENT] New dockerfile using alpine-glibc base image and make.
• [ENHANCEMENT] Other minor fixes.
• [ENHANCEMENT] Preserve alert state across reloads.
• [ENHANCEMENT] Prettify flag help output even more.
• [ENHANCEMENT] README.md updates.
• [ENHANCEMENT] Raise error on unknown config parameters.
• [ENHANCEMENT] Refine v1 HTTP API output.
• [ENHANCEMENT] Show original configuration file contents on status page instead of serialized YAML.
• [ENHANCEMENT] Start HUP signal handler earlier to not exit upon HUP during startup.
• [ENHANCEMENT] Updated vendored dependencies.
• [BUGFIX] Do not panic in StringToDuration() on wrong duration unit.
• [BUGFIX] Exit on invalid rule files on startup.
• [BUGFIX] Fix a regression in the .Path console template variable.
• [BUGFIX] Fix chunk descriptor loading.
• [BUGFIX] Fix consoles "Prometheus" link to point to /
• [BUGFIX] Fix empty configuration file cases
• [BUGFIX] Fix float to int conversions in chunk encoding, which were broken for some architectures.
• [BUGFIX] Fix overflow detection for serverset config.
• [BUGFIX] Fix race conditions in retrieval layer.
• [BUGFIX] Fix shutdown deadlock in Consul SD code.
• [BUGFIX] Fix the race condition targets in the Makefile.
• [BUGFIX] Fix value display error in web console.
• [BUGFIX] Hide authentication credentials in config String() output.
• [BUGFIX] Increment dirty counter metric in storage only if setDirty(true) is called.
• [BUGFIX] Periodically refresh services in Consul to recover from missing events.
• [BUGFIX] Prevent overwrite of default global config when loading a configuration.
• [BUGFIX] Properly lex \r as whitespace in expression language.
• [BUGFIX] Validate label names in JSON target groups.
• [BUGFIX] Validate presence of regex field in relabeling configurations.
• [CLEANUP] Clean up initialization of remote storage queues.
• [CLEANUP] Fix go vet and golint violations.
• [CLEANUP] General cleanup of rules and query language code.
• [CLEANUP] Improve and simplify Dockerfile build steps.
• [CLEANUP] Improve and simplify build infrastructure, use go-bindata for web assets. Allow building without git.
• [CLEANUP] Move all utility packages into common util subdirectory.
• [CLEANUP] Refactor main, flag handling, and web package.
• [CLEANUP] Remove unused methods from Rule interface.
• [CLEANUP] Simplify default config handling.
• [CLEANUP] Switch human-readable times on web UI to UTC.
• [CLEANUP] Use templates.TemplateExpander for all page templates.
• [CLEANUP] Use new v1 HTTP API for querying and graphing.

0.14.0 / 2015-06-01

• [CHANGE] Configuration format changed and switched to YAML. (See the provided migration tool.)
• [ENHANCEMENT] Redesign of state-preserving target discovery.
• [ENHANCEMENT] Allow specifying scrape URL scheme and basic HTTP auth for non-static targets.
• [FEATURE] Allow attaching meaningful labels to targets via relabeling.
• [FEATURE] Configuration/rule reloading at runtime.
• [FEATURE] Target discovery via file watches.
• [FEATURE] Target discovery via Consul.
• [ENHANCEMENT] Simplified binary operation evaluation.
• [ENHANCEMENT] More stable component initialization.
• [ENHANCEMENT] Added internal expression testing language.
• [BUGFIX] Fix graph links with path prefix.
• [ENHANCEMENT] Allow building from source without git.
• [ENHANCEMENT] Improve storage iterator performance.
• [ENHANCEMENT] Change logging output format and flags.
• [BUGFIX] Fix memory alignment bug for 32bit systems.
• [ENHANCEMENT] Improve web redirection behavior.
• [ENHANCEMENT] Allow overriding default hostname for Prometheus URLs.
• [BUGFIX] Fix double slash in URL sent to alertmanager.
• [FEATURE] Add resets() query function to count counter resets.
• [FEATURE] Add changes() query function to count the number of times a gauge changed.
• [FEATURE] Add increase() query function to calculate a counter's increase.
• [ENHANCEMENT] Limit retrievable samples to the storage's retention window.

0.13.4 / 2015-05-23

• [BUGFIX] Fix a race while checkpointing fingerprint mappings.

0.13.3 / 2015-05-11

• [BUGFIX] Handle fingerprint collisions properly.
• [CHANGE] Comments in rules file must start with #. (The undocumented // and /*...*/ comment styles are no longer supported.)
• [ENHANCEMENT] Switch to custom expression language parser and evaluation engine, which generates better error messages, fixes some parsing edge-cases, and enables other future enhancements (like the ones below).
• [ENHANCEMENT] Limit maximum number of concurrent queries.
• [ENHANCEMENT] Terminate running queries during shutdown.

0.13.2 / 2015-05-05

• [MAINTENANCE] Updated vendored dependencies to their newest versions.
• [MAINTENANCE] Include rule_checker and console templates in release tarball.
• [BUGFIX] Sort NaN as the lowest value.
• [ENHANCEMENT] Add square root, stddev and stdvar functions.
• [BUGFIX] Use scrape_timeout for scrape timeout, not scrape_interval.
• [ENHANCEMENT] Improve chunk and chunkDesc loading, increase performance when reading from disk.
• [BUGFIX] Show correct error on wrong DNS response.

0.13.1 / 2015-04-09

• [BUGFIX] Treat memory series with zero chunks correctly in series maintenance.
• [ENHANCEMENT] Improve readability of usage text even more.

0.13.0 / 2015-04-08

• [ENHANCEMENT] Double-delta encoding for chunks, saving typically 40% of space, both in RAM and on disk.
• [ENHANCEMENT] Redesign of chunk persistence queuing, increasing performance on spinning disks significantly.
• [ENHANCEMENT] Redesign of sample ingestion, increasing ingestion performance.
• [FEATURE] Added ln, log2, log10 and exp functions to the query language.
• [FEATURE] Experimental write support to InfluxDB.
• [FEATURE] Allow custom timestamps in instant query API.
• [FEATURE] Configurable path prefix for URLs to support proxies.
• [ENHANCEMENT] Increase of rule_checker CLI usability.
• [CHANGE] Show special float values as gaps.
• [ENHANCEMENT] Made usage output more readable.
• [ENHANCEMENT] Increased resilience of the storage against data corruption.
• [ENHANCEMENT] Various improvements around chunk encoding.
• [ENHANCEMENT] Nicer formatting of target health table on /status.
• [CHANGE] Rename UNREACHABLE to UNHEALTHY, ALIVE to HEALTHY.
• [BUGFIX] Strip trailing slash in alertmanager URL.
• [BUGFIX] Avoid +InfYs and similar, just display +Inf.
• [BUGFIX] Fixed HTML-escaping at various places.
• [BUGFIX] Fixed special value handling in division and modulo of the query language.
• [BUGFIX] Fix embed-static.sh.
• [CLEANUP] Added intial HTTP API tests.
• [CLEANUP] Misc. other code cleanups.
• [MAINTENANCE] Updated vendored dependcies to their newest versions.

0.12.0 / 2015-03-04

• [CHANGE] Use client_golang v0.3.1. THIS CHANGES FINGERPRINTING AND INVALIDATES ALL PERSISTED FINGERPRINTS. You have to wipe your storage to use this or later versions. There is a version guard in place that will prevent you to run Prometheus with the stored data of an older Prometheus.
• [BUGFIX] The change above fixes a weakness in the fingerprinting algorithm.
• [ENHANCEMENT] The change above makes fingerprinting faster and less allocation intensive.
• [FEATURE] OR operator and vector matching options. See docs for details.
• [ENHANCEMENT] Scientific notation and special float values (Inf, NaN) now supported by the expression language.
• [CHANGE] Dockerfile makes Prometheus use the Docker volume to store data (rather than /tmp/metrics).
• [CHANGE] Makefile uses Go 1.4.2.

0.11.1 / 2015-02-27

• [BUGFIX] Make series maintenance complete again. (Ever since 0.9.0rc4, or commit 0851945, series would not be archived, chunk descriptors would not be evicted, and stale head chunks would never be closed. This happened due to accidental deletion of a line calling a (well tested :) function.
• [BUGFIX] Do not double count head chunks read from checkpoint on startup. Also fix a related but less severe bug in counting chunk descriptors.
• [BUGFIX] Check last time in head chunk for head chunk timeout, not first.
• [CHANGE] Update vendoring due to vendoring changes in client_golang.
• [CLEANUP] Code cleanups.
• [ENHANCEMENT] Limit the number of 'dirty' series counted during checkpointing.

0.11.0 / 2015-02-23

• [FEATURE] Introduce new metric type Histogram with server-side aggregation.
• [FEATURE] Add offset operator.
• [FEATURE] Add floor, ceil and round functions.
• [CHANGE] Change instance identifiers to be host:port.
• [CHANGE] Dependency management and vendoring changed/improved.
• [CHANGE] Flag name changes to create consistency between various Prometheus binaries.
• [CHANGE] Show unlimited number of metrics in autocomplete.
• [CHANGE] Add query timeout.
• [CHANGE] Remove labels on persist error counter.
• [ENHANCEMENT] Various performance improvements for sample ingestion.
• [ENHANCEMENT] Various Makefile improvements.
• [ENHANCEMENT] Various console template improvements, including proof-of-concept for federation via console templates.
• [ENHANCEMENT] Fix graph JS glitches and simplify graphing code.
• [ENHANCEMENT] Dramatically decrease resources for file embedding.
• [ENHANCEMENT] Crash recovery saves lost series data in 'orphaned' directory.
• [BUGFIX] Fix aggregation grouping key calculation.
• [BUGFIX] Fix Go download path for various architectures.
• [BUGFIX] Fixed the link of the Travis build status image.
• [BUGFIX] Fix Rickshaw/D3 version mismatch.
• [CLEANUP] Various code cleanups.

0.10.0 / 2015-01-26

• [CHANGE] More efficient JSON result format in query API. This requires up-to-date versions of PromDash and prometheus_cli, too.
• [ENHANCEMENT] Excluded non-minified Bootstrap assets and the Bootstrap maps from embedding into the binary. Those files are only used for debugging, and then you can use -web.use-local-assets. By including fewer files, the RAM usage during compilation is much more manageable.
• [ENHANCEMENT] Help link points to http://prometheus.github.io now.
• [FEATURE] Consoles for haproxy and cloudwatch.
• [BUGFIX] Several fixes to graphs in consoles.
• [CLEANUP] Removed a file size check that did not check anything.

0.9.0 / 2015-01-23

• [CHANGE] Reworked command line flags, now more consistent and taking into account needs of the new storage backend (see below).
• [CHANGE] Metric names are dropped after certain transformations.
• [CHANGE] Changed partitioning of summary metrics exported by Prometheus.
• [CHANGE] Got rid of Gerrit as a review tool.
• [CHANGE] 'Tabular' view now the default (rather than 'Graph') to avoid running very expensive queries accidentally.
• [CHANGE] On-disk format for stored samples changed. For upgrading, you have to nuke your old files completely. See "Complete rewrite of the storage
• [CHANGE] Removed 2nd argument from delta.
• [FEATURE] Added a deriv function.
• [FEATURE] Console templates.
• [FEATURE] Added absent function.
• [FEATURE] Allow omitting the metric name in queries.
• [BUGFIX] Removed all known race conditions.
• [BUGFIX] Metric mutations now handled correctly in all cases.
• [ENHANCEMENT] Proper double-start protection.
• [ENHANCEMENT] Complete rewrite of the storage layer. Benefits include:
  • Better query performance.
  • More samples in less RAM.
  • Better memory management.
  • Scales up to millions of time series and thousands of samples ingested per second.
  • Purging of obsolete samples much cleaner now, up to completely "forgetting" obsolete time series.
  • Proper instrumentation to diagnose the storage layer with... well... Prometheus.
  • Pure Go implementation, no need for cgo and shared C libraries anymore.
  • Better concurrency.
• [ENHANCEMENT] Copy-on-write semantics in the AST layer.
• [ENHANCEMENT] Switched from Go 1.3 to Go 1.4.
• [ENHANCEMENT] Vendored external dependencies with godeps.
• [ENHANCEMENT] Numerous Web UI improvements, moved to Bootstrap3 and Rickshaw 1.5.1.
• [ENHANCEMENT] Improved Docker integration.
• [ENHANCEMENT] Simplified the Makefile contraption.
• [CLEANUP] Put meta-data files into proper shape (LICENSE, README.md etc.)
• [CLEANUP] Removed all legitimate 'go vet' and 'golint' warnings.
• [CLEANUP] Removed dead code.

0.8.0 / 2014-09-04

• [ENHANCEMENT] Stagger scrapes to spread out load.
• [BUGFIX] Correctly quote HTTP Accept header.

0.7.0 / 2014-08-06

• [FEATURE] Added new functions: abs(), topk(), bottomk(), drop_common_labels().
• [FEATURE] Let console templates get graph links from expressions.
• [FEATURE] Allow console templates to dynamically include other templates.
• [FEATURE] Template consoles now have access to their URL.
• [BUGFIX] Fixed time() function to return evaluation time, not wallclock time.
• [BUGFIX] Fixed HTTP connection leak when targets returned a non-200 status.
• [BUGFIX] Fixed link to console templates in UI.
• [PERFORMANCE] Removed extra memory copies while scraping targets.
• [ENHANCEMENT] Switched from Go 1.2.1 to Go 1.3.
• [ENHANCEMENT] Made metrics exported by Prometheus itself more consistent.
• [ENHANCEMENT] Removed incremental backoffs for unhealthy targets.
• [ENHANCEMENT] Dockerfile also builds Prometheus support tools now.

0.6.0 / 2014-06-30

• [FEATURE] Added console and alert templates support, along with various template functions.
• [PERFORMANCE] Much faster and more memory-efficient flushing to disk.
• [ENHANCEMENT] Query results are now only logged when debugging.
• [ENHANCEMENT] Upgraded to new Prometheus client library for exposing metrics.
• [BUGFIX] Samples are now kept in memory until fully flushed to disk.
• [BUGFIX] Non-200 target scrapes are now treated as an error.
• [BUGFIX] Added installation step for missing dependency to Dockerfile.
• [BUGFIX] Removed broken and unused "User Dashboard" link.

0.5.0 / 2014-05-28

• [BUGFIX] Fixed next retrieval time display on status page.
• [BUGFIX] Updated some variable references in tools subdir.
• [FEATURE] Added support for scraping metrics via the new text format.
• [PERFORMANCE] Improved label matcher performance.
• [PERFORMANCE] Removed JSON indentation in query API, leading to smaller response sizes.
• [ENHANCEMENT] Added internal check to verify temporal order of streams.
• [ENHANCEMENT] Some internal refactorings.

0.4.0 / 2014-04-17

• [FEATURE] Vectors and scalars may now be reversed in binary operations (<scalar> <binop> <vector>).
• [FEATURE] It's possible to shutdown Prometheus via a /-/quit web endpoint now.
• [BUGFIX] Fix for a deadlock race condition in the memory storage.
• [BUGFIX] Mac OS X build fixed.
• [BUGFIX] Built from Go 1.2.1, which has internal fixes to race conditions in garbage collection handling.
• [ENHANCEMENT] Internal storage interface refactoring that allows building e.g. the rule_checker tool without LevelDB dynamic library dependencies.
• [ENHANCEMENT] Cleanups around shutdown handling.
• [PERFORMANCE] Preparations for better memory reuse during marshalling / unmarshalling.