Commit graph

69 commits

Author SHA1 Message Date
beorn7 5de2df752f Hacky implementation of protobuf parsing
This "brings back" protobuf parsing, with the only goal to play with
the new sparse histograms.

The Prom-2.x style parser is highly adapted to the structure of the
Prometheus text format (and later OpenMetrics). Some jumping through
hoops is required to feed protobuf into it.

This is not meant to be a model for the final implementation. It
should just enable sparse histogram ingestion at a reasonable
efficiency.

Following known shortcomings and flaws:

- No tests yet.

- Summaries and legacy histograms, i.e. without sparse buckets, are
  ignored.

- Staleness doesn't work (but this could be fixed in the appender, to
  be discussed).

- No tricks have been tried that would be similar to the tricks the
  text parsers do (like direct pointers into the HTTP response
  body). That makes things weird here. Tricky optimizations only make
  sense once the final format is specified, which will almost
  certainly not be the old protobuf format. (Interestingly, I expect
  this implementation to be in fact much more efficient than the
  original protobuf ingestion in Prom-1.x.)

- This is using a proto3 version of metrics.proto (mostly to be
  consistent with the other protobuf uses). However, proto3 sees no
  difference between an unset field. We depend on that to distinguish
  between an unset timestamp and the timestamp 0 (1970-01-01, 00:00:00
  UTC). In this experimental code, we just assume that timestamp is
  never specified and therefore a timestamp of 0 always is interpreted
  as "not set".

Signed-off-by: beorn7 <beorn@grafana.com>
2021-07-01 01:35:11 +02:00
Julius Volz 9d495afd2c Remove trailing zeros in scrape timeout header
See https://twitter.com/AviKivity/status/1405147699557638145 and
https://twitter.com/juliusvolz/status/1405790211670515712

Signed-off-by: Julius Volz <julius.volz@gmail.com>
2021-06-18 09:38:12 +02:00
Levi Harrison b5f6f8fb36 Switched to go-kit/log
Signed-off-by: Levi Harrison <git@leviharrison.dev>
2021-06-11 12:28:36 -04:00
hanjm 1df05bfd49 Add body_size_limit to prevent bad targets response large body cause Prometheus server OOM (#8827)
Signed-off-by: hanjm <hanjinming@outlook.com>
2021-05-29 07:05:42 +08:00
Damien Grisonnet b50f9c1c84
Add label scrape limits (#8777)
* scrape: add label limits per scrape

Add three new limits to the scrape configuration to provide some
mechanism to defend against unbound number of labels and excessive
label lengths. If any of these limits are broken by a sample from a
scrape, the whole scrape will fail. For all of these configuration
options, a zero value means no limit.

The `label_limit` configuration will provide a mechanism to bound the
number of labels per-scrape of a certain sample to a user defined limit.
This limit will be tested against the sample labels plus the discovery
labels, but it will exclude the __name__ from the count since it is a
mandatory Prometheus label to which applying constraints isn't
meaningful.

The `label_name_length_limit` and `label_value_length_limit` will
prevent having labels of excessive lengths. These limits also skip the
__name__ label for the same reasons as the `label_limit` option and will
also make the scrape fail if any sample has a label name/value length
that exceed the predefined limits.

Signed-off-by: Damien Grisonnet <dgrisonn@redhat.com>

* scrape: add metrics and alert to label limits

Add three gauge, one for each label limit to easily access the
limit set by a certain scrape target.
Also add a counter to count the number of targets that exceeded the
label limits and thus were dropped. This is useful for the
`PrometheusLabelLimitHit` alert that will notify the users that scraping
some targets failed because they had samples exceeding the label limits
defined in the scrape configuration.

Signed-off-by: Damien Grisonnet <dgrisonn@redhat.com>

* scrape: apply label limits to __name__ label

Apply limits to the __name__ label that was previously skipped and
truncate the label names and values in the error messages as they can be
very very long.

Signed-off-by: Damien Grisonnet <dgrisonn@redhat.com>

* scrape: remove label limits gauges and refactor

Remove `prometheus_target_scrape_pool_label_limit`,
`prometheus_target_scrape_pool_label_name_length_limit`, and
`prometheus_target_scrape_pool_label_value_length_limit` as they are not
really useful since we don't have the information on the labels in it.

Signed-off-by: Damien Grisonnet <dgrisonn@redhat.com>
2021-05-06 09:56:21 +01:00
Callum Styan 289ba11b79
Add circular in-memory exemplars storage (#6635)
* Add circular in-memory exemplars storage

Signed-off-by: Callum Styan <callumstyan@gmail.com>
Signed-off-by: Tom Wilkie <tom.wilkie@gmail.com>
Signed-off-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>
Signed-off-by: Martin Disibio <mdisibio@gmail.com>

Co-authored-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>
Co-authored-by: Tom Wilkie <tom.wilkie@gmail.com>
Co-authored-by: Martin Disibio <mdisibio@gmail.com>

* Fix some comments, clean up exemplar metrics struct and exemplar tests.

Signed-off-by: Callum Styan <callumstyan@gmail.com>

* Fix exemplar query api null vs empty array issue.

Signed-off-by: Callum Styan <callumstyan@gmail.com>

Co-authored-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>
Co-authored-by: Tom Wilkie <tom.wilkie@gmail.com>
Co-authored-by: Martin Disibio <mdisibio@gmail.com>
2021-03-16 15:17:45 +05:30
Tom Wilkie 7369561305
Combine Appender.Add and AddFast into a single Append method. (#8489)
This moves the label lookup into TSDB, whilst still keeping the cached-ref optimisation for repeated Appends.

This makes the API easier to consume and implement.  In particular this change is motivated by the scrape-time-aggregation work, which I don't think is possible to implement without it as it needs access to label values.

Signed-off-by: Tom Wilkie <tom.wilkie@gmail.com>
2021-02-18 17:37:00 +05:30
Julien Pivotto 6c56a1faaa
Testify: move to require (#8122)
* Testify: move to require

Moving testify to require to fail tests early in case of errors.

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>

* More moves

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-10-29 09:43:23 +00:00
Julien Pivotto 1282d1b39c
Refactor test assertions (#8110)
* Refactor test assertions

This pull request gets rid of assert.True where possible to use
fine-grained assertions.

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-10-27 11:06:53 +01:00
Julien Pivotto 4e5b1722b3
Move away from testutil, refactor imports (#8087)
Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-10-22 11:00:08 +02:00
Julien Pivotto 6f13c60219
Scrape: Test that deduplicated targets are started (#7975)
This PR test that de-duplicated targets are actually started.

It is a unit test for this line of code:
072b9649a3/scrape/scrape.go (L457)
which is working and necessary but was not tested yet.

It also tests that scrapes are started in the normal way, in the targets
limit test.

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-09-30 20:21:32 +02:00
Julien Pivotto 2899773b01
Do not stop scrapes in progress during reload (#7752)
* Do not stop scrapes in progress during reload.

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-08-07 15:58:16 +02:00
Annanay ec562f152b Merge branch 'master' into appender-context
Signed-off-by: Annanay <annanayagarwal@gmail.com>
2020-07-31 13:03:56 +05:30
Julien Pivotto f482c7bdd7
Add per scrape-config targets limit (#7554)
* Add per scrape-config targets limit

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-07-30 14:20:24 +02:00
Annanay 9bba8a6eae Merge branch 'master' into appender-context
Signed-off-by: Annanay <annanayagarwal@gmail.com>
2020-07-30 16:43:18 +05:30
Annanay 89129cd39a Address comments
Signed-off-by: Annanay <annanayagarwal@gmail.com>
2020-07-30 16:41:13 +05:30
Julien Pivotto e76c436e9c
Goleak in discoveries, scrape, rules (#7662)
* Add go leak tests for discoveries with goroutines

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>

* Add go leak tests in rules

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>

* Add go leak tests in scrape tests

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-07-27 09:38:08 +01:00
Annanay 7f98a744e5 Add context to Appender interface
Signed-off-by: Annanay <annanayagarwal@gmail.com>
2020-07-24 19:40:51 +05:30
Julien Pivotto 22aa21e508
scrape tests: Make appenders more realistic (#7594)
With this, the storage tests inside the scrape package are more
realistic.

Discovered with #7593, but fixed independently as #7593 will probably
take some time.

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-07-17 12:30:22 +02:00
Julien Pivotto 754461b74f
Reuse the same appender for report and scrape (#7562)
Additionally, implement isolation in collectResultAppender.

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-07-16 13:53:39 +02:00
Kemal Akkoyun 66dfb951c4
*: Consistent Error/Warning handling for SeriesSet iterator: Allowing Async Select (#7251)
* Add errors and Warnings to SeriesSet

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Change Querier interface and refactor accordingly

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Refactor promql/engine to propagate warnings at eval stage

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Address review issues

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Make sure all the series from all Selects are pre-advanced

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Address review issues

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Separate merge series sets

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Clean

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Refactor merge querier failure handling

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Refactored and simplified fanout with improvements from incoming chunk iterator PRs.

* Secondary logic is hidden, instead of weird failed series set logic we had.
* Fanout is well commented
* Fanout closing record all errors
* MergeQuerier improved API (clearer)
* deferredGenericMergeSeriesSet is not needed as we return no samples anyway for failed series sets (next = false).

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>

* Fix formatting

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Fix CI issues

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Added final tests for error handling.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>

* Addressed Brian's comments.

* Moved hints in populate to be allocated only when needed.
* Used sync.Once in secondary Querier to achieve all-or-nothing partial response logic.
* Select after first Next is done will panic.

NOTE: in lazySeriesSet in theory we could just panic, I think however we can
totally just return error, it will panic in expand anyway.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>

* Utilize errWithWarnings

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Fix recently introduced expansion issue

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Add tests for secondary querier error handling

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Implement lazy merge

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Add name to test cases

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Reorganize

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Address review comments

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Address review comments

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Remove redundant warnings

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

* Fix rebase mistake

Signed-off-by: Kemal Akkoyun <kakkoyun@gmail.com>

Co-authored-by: Bartlomiej Plotka <bwplotka@gmail.com>
2020-06-09 17:57:31 +01:00
Brian Brazil f9d21f10ec
Only relabelling should apply for scrape_samples_scraped_post_relabelling. (#7342)
More consistent variable names.

Fixes #7298

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
2020-06-04 16:00:37 +01:00
Brian Brazil c9565f08aa
Pass reference to checkAddError so appendErrors is updated. (#7294)
This was preventing the warnings from being logged.

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
2020-05-26 15:14:55 +01:00
ZouYu 2b7437d60e
Fix some warnings: 'redundant type from array, slice, or map composite literal' (#7109)
Signed-off-by: ZouYu <zouy.fnst@cn.fujitsu.com>
2020-04-15 11:17:41 +01:00
Callum Styan c453def8c5
Separate scrape add error checking out into it's own function. (#6930)
* Separate scrape add error checking out into it's own function.

Signed-off-by: Callum Styan <callumstyan@gmail.com>

* pass sampleLimitError to checkAddError instead of returning an error

Signed-off-by: Callum Styan <callumstyan@gmail.com>

* Return bool, error from checkAddError so we can properly handle
ErrNotFound for AddFast. This should in theory never happen, but the
previous code path handled this case. Adds a test for this, which master
passes and the previous commit fails.

Signed-off-by: Callum Styan <callumstyan@gmail.com>

* Address comment changes.

Signed-off-by: Callum Styan <callumstyan@gmail.com>

* Move sampleAdded inside the loop iteration within append, since that's
the only block the variable is used in.

Signed-off-by: Callum Styan <callumstyan@gmail.com>
2020-03-25 19:31:48 -07:00
Bartlomiej Plotka c4eefd1b3a storage: Removed SelectSorted method; Simplified interface; Added requirement for remote read to sort response.
This is technically BREAKING CHANGE, but it was like this from the beginning: I just notice that we rely in
Prometheus on remote read being sorted. This is because we use selected data from remote reads in MergeSeriesSet
which rely on sorting.

I found during work on https://github.com/prometheus/prometheus/pull/5882 that
we do so many repetitions because of this, for not good reason. I think
I found a good balance between convenience and readability with just one method.
Smaller the interface = better.

Also I don't know what TestSelectSorted was testing, but now it's testing sorting.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
2020-03-20 21:14:43 +01:00
Julien Pivotto d6ad5551c9
Scrape: do not put staleness marker when cache is reused (#7011)
* Scrape: do not put staleness marker when cache is reused

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-03-20 17:43:26 +01:00
Julien Pivotto 8907ba6235 Make TSDB use storage errors
This fixes #6992, which was introduced by #6777. There was an
intermediate component which translated TSDB errors into storage errors,
but that component was deleted and this bug went unnoticed, until we
were watching at the Prombench results. Without this, scrape will fail
instead of dropping samples or using "Add" when the series have been
garbage collected.

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-03-17 22:24:25 +01:00
Julien Pivotto ed623f69e2
tsdb: don't allow ingesting empty labelsets (#6891)
* tsdb: don't allow ingesting empty labelsets

When we ingest an empty labelset in the head, further blocks can not be
compacted, with the error:

```
level=error ts=2020-02-27T21:26:58.379Z caller=db.go:659 component=tsdb
msg="compaction failed" err="persist head block: write compaction:
add series: out-of-order series added with label set \"{}\" / prev:
\"{}\""
```

We should therefore reject those invalid empty labelsets upfront.

This can be reproduced with the following:

```
cat << END > prometheus.yml
scrape_configs:
  - job_name: 'prometheus'
    scrape_interval: 1s
    basic_auth:
      username: test
      password: test
    metric_relabel_configs:
    - regex: ".*"
      action: labeldrop

    static_configs:
    - targets:
      - 127.0.1.1:9090
END
./prometheus --storage.tsdb.min-block-duration=1m
```
And wait a few minutes.

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-03-02 07:18:05 +00:00
Boqin Qin 0e51cf65e7
scrape_test: fix send-to-closed-channel bugs (#6849)
Signed-off-by: BurtonQin <bobbqqin@gmail.com>
2020-02-20 13:40:25 +00:00
Bartlomiej Plotka 34426766d8 Unify Iterator interfaces. All point to storage now.
This is part of https://github.com/prometheus/prometheus/pull/5882 that can be done to simplify things.
All todos I added will be fixed in follow up PRs.

* querier.Querier, querier.Appender, querier.SeriesSet, and querier.Series interfaces merged
with storage interface.go. All imports that.
* querier.SeriesIterator replaced by chunkenc.Iterator
* Added chunkenc.Iterator.Seek method and tests for xor implementation (?)
* Since we properly handle SelectParams for Select methods I adjusted min max
based on that. This should help in terms of performance for queries with functions like offset.
* added Seek to deletedIterator and test.
* storage/tsdb was removed as it was only a unnecessary glue with incompatible structs.

No logic was changed, only different source of abstractions, so no need for benchmarks.

Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
2020-02-17 18:03:54 +00:00
Boqin Qin cdbd42393e
scrape: fix goroutine leak in test (#6812)
* scrape: fix goroutine leak in test

Signed-off-by: BurtonQin <bobbqqin@gmail.com>
2020-02-13 07:53:07 +00:00
Julien Pivotto 9c67fce6e0
Scrape: test samples_post_metric_relabeling when metrics are dropped (#6720)
Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-01-29 17:47:36 +00:00
Julien Pivotto fafb7940b1 Pass over scrape cache to the next scrape (#6670)
* Pass over scrape cache to the next scrape

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-01-22 12:13:47 +00:00
Julien Pivotto 46d18112a3 tsdb: error on series with duplicate labels (#6664)
Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2020-01-20 11:05:27 +00:00
gotjosh 05842176a6 Make the scrape.metricMetadataStore interface public
To test the implementation of our metric metadata API, we need to represent various states of metadata in the scrape metadata store. That is currently not possible as the interface and method to set the store are private.

This changes the interface, list and get methods, and the SetMetadaStore function to be public.

Incidentally, the scrapeCache implementation needs to be renamed to match the new signature.

Signed-off-by: gotjosh <josue@grafana.com>
2019-12-05 10:29:58 +00:00
Geoffrey Beausire 5cb7987314 Fix relabaling collision when using exported label
When using both a label and the suffix+label in the
relabel config. It's possible that Prometheus remove
the suffx+label for no obvious reason. It's due to a
collision when merging labels from target and from
the sample.

Signed-off-by: Geoffrey Beausire <g.beausire@criteo.com>
2019-11-26 11:03:11 +01:00
Dustin Hooten ca60bf298c React UI: Implement /targets page (#6276)
* Add LastScrapeDuration to targets endpoint

Signed-off-by: Dustin Hooten <dhooten@splunk.com>

* Add Scrape job name to targets endpoint

Signed-off-by: Dustin Hooten <dhooten@splunk.com>

* Implement the /targets page in react

Signed-off-by: Dustin Hooten <dhooten@splunk.com>

* Add state query param to targets endpoint

Signed-off-by: Dustin Hooten <dhooten@splunk.com>

* Use state filter in api call

Signed-off-by: Dustin Hooten <dhooten@splunk.com>

* api feedback

Signed-off-by: Dustin Hooten <dhooten@splunk.com>

* pr feedback frontend

Signed-off-by: Dustin Hooten <dhooten@splunk.com>

* Implement and use localstorage hook

Signed-off-by: Dustin Hooten <dhooten@splunk.com>

* PR feedback

Signed-off-by: Dustin Hooten <dhooten@splunk.com>
2019-11-11 22:42:24 +01:00
Alex Dzyoba 1a38075f83 scrape: Move tests to testutil (#6187)
Part of the fix for #3242.

Signed-off-by: Alex Dzyoba <alex@dzyoba.com>
2019-11-04 16:43:42 -07:00
yuxiaobo 47e51c8b2b Correct spelling mistakes
Signed-off-by: yuxiaobo <yuxiaobogo@163.com>
2019-10-10 18:46:27 +08:00
Brian Brazil e62f30d497
Correctly handle empty labels from alert templates. (#5845)
Fixes https://github.com/prometheus/common/issues/36

Move logic handling this into the labels package,
so all the cases are handled in one place and we're
less likely to have this come up again.

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
2019-08-13 11:19:17 +01:00
Chris Marchbanks 529ccff07b
Remove all usages of stretchr/testify
Signed-off-by: Chris Marchbanks <csmarchbanks@gmail.com>
2019-08-08 19:49:27 -06:00
Chris Marchbanks 0685eb5395
Refactor testutil.NewStorage into a new package
This avoids a circular dependency between the testutil and storage
packages.

Signed-off-by: Chris Marchbanks <csmarchbanks@gmail.com>
2019-08-08 19:43:04 -06:00
Brian Brazil b98e818876
Add scrape_series_added per-scrape metric. (#5546)
This is an estimate of churn, with series being added to the cache being
considered churn. This will have both false positives (e.g. series
appearing and disappearing) and false negatives (e.g. series hit
sample_limit, but still created in head block), but should be generally
useful as-is.

Relevant docs live in another repo.

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
2019-05-08 22:24:00 +01:00
Simon Pasquier c1682adb2f Bump prometheus/common to v0.3.0 (#5344)
* Reload certificates from disk automatically

This change bumps github.com/prometheus/common to include
https://github.com/prometheus/common/pull/173

Signed-off-by: Simon Pasquier <spasquie@redhat.com>

* scrape: close idle connections on reload/stop

Signed-off-by: Simon Pasquier <spasquie@redhat.com>

* use v0.3.0 tag

Signed-off-by: Simon Pasquier <spasquie@redhat.com>
2019-04-10 13:20:00 +01:00
Brian Brazil f7184978f4 Protect against memory exhaustion when scraping.
Now that we're not losing the scrape cache across failed
scrape, a scrape that continually failed but had varying
series or metadata (e.g. timestamps in metric names,
plus hitting smaple_limit) would grow the cache indefinitely.

Add some code to catch that, and flush the cache anyway.

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
2019-04-04 19:09:11 +01:00
Brian Brazil dd3073616c Don't lose the scrape cache on a failed scrape.
This avoids CPU usage increasing when the target comes back.

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
2019-04-04 19:09:11 +01:00
Tariq Ibrahim 8fdfa8abea refine error handling in prometheus (#5388)
i) Uses the more idiomatic Wrap and Wrapf methods for creating nested errors.
ii) Fixes some incorrect usages of fmt.Errorf where the error messages don't have any formatting directives.
iii) Does away with the use of fmt package for errors in favour of pkg/errors

Signed-off-by: tariqibrahim <tariq181290@gmail.com>
2019-03-26 00:01:12 +01:00
Julien Pivotto 4397916cb2 Add honor_timestamps (#5304)
Fixes #5302

Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
2019-03-15 10:04:15 +00:00
xjewer 0d1a69353e scrape: Add global jitter for HA server (#5181)
* scrape: Add global jitter for HA server

Covers issue in https://github.com/prometheus/prometheus/pull/4926#issuecomment-449039848
where the HA setup become a problem for targets unable to be scraped simultaneously.
The new jitter per server relies on the hostname and external labels which necessarily to be uniq.

As before, scrape offset will be calculated with regard the absolute time, so even
restart/reload doesn't change scrape time per scrape target + prometheus instance.

Use fqdn if possible, otherwise fall back to the hostname. It adds extra random seed
to calculate server hash to be distinguish on machines with the same hostname, but
different DC.

Signed-off-by: Aleksei Semiglazov <xjewer@gmail.com>
2019-03-12 10:46:15 +00:00