promql: Improve histogram_quantile calculation for classic buckets
Tiny differences between classic buckets are most likely caused by floating point precision issues. With this commit, relative changes below a certain threshold are ignored. This makes the result of histogram_quantile more meaningful, and also avoids triggering the _input to histogram_quantile needed to be fixed for monotonicity_ annotations in unactionable cases.
This commit also adds explanation of the new adjustment and of the monotonicity annotation to the documentation of `histogram_quantile`.
---------
Signed-off-by: Jeanette Tan <jeanette.tan@grafana.com>
Return annotations (warnings and infos) from PromQL queries
This generalizes the warnings we have already used before (but only for problems with remote read) as "annotations".
Annotations can be warnings or infos (the latter could be false positives). We do not treat them different in the API for now and return them all as "warnings". It would be easy to distinguish them and return infos separately, should that appear useful in the future.
The new annotations are then used to create a lot of warnings or infos during PromQL evaluations. Partially these are things we have wanted for a long time (e.g. inform the user that they have applied `rate` to a metric that doesn't look like a counter), but the new native histograms have created even more needs for those annotations (e.g. if a query tries to aggregate float numbers with histograms).
The annotations added here are not yet complete. A prominent example would be a warning about a range too short for a rate calculation. But such a warnings is more tricky to create with good fidelity and we will tackle it later.
Another TODO is to take annotations into account when evaluating recording rules.
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Signed-off-by: Jeanette Tan <jeanette.tan@grafana.com>
promql: Extend testing framework to support native histograms
This includes both the internal testing framework as well as the rules unit test feature of promtool.
This also adds a bunch of basic tests. Many of the code level tests can now be converted to tests within the framework, and more tests can be added easily.
---------
Signed-off-by: Harold Dost <h.dost@criteo.com>
Signed-off-by: Gregor Zeitlinger <gregor.zeitlinger@grafana.com>
Signed-off-by: Stephen Lang <stephen.lang@grafana.com>
Co-authored-by: Harold Dost <h.dost@criteo.com>
Co-authored-by: Stephen Lang <stephen.lang@grafana.com>
Co-authored-by: Gregor Zeitlinger <gregor.zeitlinger@grafana.com>
In other words: Instead of having a “polymorphous” `Point` that can
either contain a float value or a histogram value, use an `FPoint` for
floats and an `HPoint` for histograms.
This seemingly small change has a _lot_ of repercussions throughout
the codebase.
The idea here is to avoid the increase in size of `Point` arrays that
happened after native histograms had been added.
The higher-level data structures (`Sample`, `Series`, etc.) are still
“polymorphous”. The same idea could be applied to them, but at each
step the trade-offs needed to be evaluated.
The idea with this change is to do the minimum necessary to get back
to pre-histogram performance for functions that do not touch
histograms. Here are comparisons for the `changes` function. The test
data doesn't include histograms yet. Ideally, there would be no change
in the benchmark result at all.
First runtime v2.39 compared to directly prior to this commit:
```
name old time/op new time/op delta
RangeQuery/expr=changes(a_one[1d]),steps=1-16 391µs ± 2% 542µs ± 1% +38.58% (p=0.000 n=9+8)
RangeQuery/expr=changes(a_one[1d]),steps=10-16 452µs ± 2% 617µs ± 2% +36.48% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_one[1d]),steps=100-16 1.12ms ± 1% 1.36ms ± 2% +21.58% (p=0.000 n=8+10)
RangeQuery/expr=changes(a_one[1d]),steps=1000-16 7.83ms ± 1% 8.94ms ± 1% +14.21% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_ten[1d]),steps=1-16 2.98ms ± 0% 3.30ms ± 1% +10.67% (p=0.000 n=9+10)
RangeQuery/expr=changes(a_ten[1d]),steps=10-16 3.66ms ± 1% 4.10ms ± 1% +11.82% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_ten[1d]),steps=100-16 10.5ms ± 0% 11.8ms ± 1% +12.50% (p=0.000 n=8+10)
RangeQuery/expr=changes(a_ten[1d]),steps=1000-16 77.6ms ± 1% 87.4ms ± 1% +12.63% (p=0.000 n=9+9)
RangeQuery/expr=changes(a_hundred[1d]),steps=1-16 30.4ms ± 2% 32.8ms ± 1% +8.01% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_hundred[1d]),steps=10-16 37.1ms ± 2% 40.6ms ± 2% +9.64% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_hundred[1d]),steps=100-16 105ms ± 1% 117ms ± 1% +11.69% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_hundred[1d]),steps=1000-16 783ms ± 3% 876ms ± 1% +11.83% (p=0.000 n=9+10)
```
And then runtime v2.39 compared to after this commit:
```
name old time/op new time/op delta
RangeQuery/expr=changes(a_one[1d]),steps=1-16 391µs ± 2% 547µs ± 1% +39.84% (p=0.000 n=9+8)
RangeQuery/expr=changes(a_one[1d]),steps=10-16 452µs ± 2% 616µs ± 2% +36.15% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_one[1d]),steps=100-16 1.12ms ± 1% 1.26ms ± 1% +12.20% (p=0.000 n=8+10)
RangeQuery/expr=changes(a_one[1d]),steps=1000-16 7.83ms ± 1% 7.95ms ± 1% +1.59% (p=0.000 n=10+8)
RangeQuery/expr=changes(a_ten[1d]),steps=1-16 2.98ms ± 0% 3.38ms ± 2% +13.49% (p=0.000 n=9+10)
RangeQuery/expr=changes(a_ten[1d]),steps=10-16 3.66ms ± 1% 4.02ms ± 1% +9.80% (p=0.000 n=10+9)
RangeQuery/expr=changes(a_ten[1d]),steps=100-16 10.5ms ± 0% 10.8ms ± 1% +3.08% (p=0.000 n=8+10)
RangeQuery/expr=changes(a_ten[1d]),steps=1000-16 77.6ms ± 1% 78.1ms ± 1% +0.58% (p=0.035 n=9+10)
RangeQuery/expr=changes(a_hundred[1d]),steps=1-16 30.4ms ± 2% 33.5ms ± 4% +10.18% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_hundred[1d]),steps=10-16 37.1ms ± 2% 40.0ms ± 1% +7.98% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_hundred[1d]),steps=100-16 105ms ± 1% 107ms ± 1% +1.92% (p=0.000 n=10+10)
RangeQuery/expr=changes(a_hundred[1d]),steps=1000-16 783ms ± 3% 775ms ± 1% -1.02% (p=0.019 n=9+9)
```
In summary, the runtime doesn't really improve with this change for
queries with just a few steps. For queries with many steps, this
commit essentially reinstates the old performance. This is good
because the many-step queries are the one that matter most (longest
absolute runtime).
In terms of allocations, though, this commit doesn't make a dent at
all (numbers not shown). The reason is that most of the allocations
happen in the sampleRingIterator (in the storage package), which has
to be addressed in a separate commit.
Signed-off-by: beorn7 <beorn@grafana.com>
We use `labels.Builder` to parse metrics, to avoid depending on the
internal implementation. This is not efficient, but the feature is only
used in tests. It wasn't efficient previously either - calling `Sort()`
after adding each label.
`createLabelsForAbsentFunction` also uses a Builder now, and gets
an extra `map` to replace the previous `Has()` usage.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
Fix up promql to compile with changes to Labels
* Switch from 'sanity' to more inclusive lanuage
"Removing ableist language in code is important; it helps to create and
maintain an environment that welcomes all developers of all backgrounds,
while emphasizing that we as developers select the most articulate,
precise, descriptive language we can rather than relying on metaphors.
The phrase sanity check is ableist, and unnecessarily references mental
health in our code bases. It denotes that people with mental illnesses
are inferior, wrong, or incorrect, and the phrase sanity continues to be
used by employers and other individuals to discriminate against these
people."
From https://gist.github.com/seanmhanson/fe370c2d8bd2b3228680e38899baf5cc
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
* Update go to 1.19, set min version to 1.18
Signed-off-by: Julien Pivotto <roidelapluie@o11y.eu>
* Update golangci-lint
Signed-off-by: Julien Pivotto <roidelapluie@o11y.eu>
Signed-off-by: Julien Pivotto <roidelapluie@o11y.eu>
* refactor: move from io/ioutil to io and os packages
* use fs.DirEntry instead of os.FileInfo after os.ReadDir
Signed-off-by: MOREL Matthieu <matthieu.morel@cnp.fr>
We always track total samples queried and add those to the standard set
of stats queries can report.
We also allow optionally tracking per-step samples queried. This must be
enabled both at the engine and query level to be tracked and rendered.
The engine flag is exposed via a Prometheus feature flag, while the
query flag is set when stats=all.
Co-authored-by: Alan Protasio <approtas@amazon.com>
Co-authored-by: Andrew Bloomgarden <blmgrdn@amazon.com>
Co-authored-by: Harkishen Singh <harkishensingh@hotmail.com>
Signed-off-by: Andrew Bloomgarden <blmgrdn@amazon.com>
This follows the line of argument that the invariant of not looking
ahead of the query time was merely emerging behavior and not a
documented stable feature. Any query that looks ahead of the query
time was simply invalid before the introduction of the negative offset
and the @ modifier.
Signed-off-by: beorn7 <beorn@grafana.com>
This creates a new `model` directory and moves all data-model related
packages over there:
exemplar labels relabel rulefmt textparse timestamp value
All the others are more or less utilities and have been moved to `util`:
gate logging modetimevfs pool runtime
Signed-off-by: beorn7 <beorn@grafana.com>
* Added feature flag support to unit tests
Signed-off-by: Levi Harrison <git@leviharrison.dev>
* Added/fixed tests
Signed-off-by: Levi Harrison <git@leviharrison.dev>
* Addressed review comments
Signed-off-by: Levi Harrison <git@leviharrison.dev>
* Write exemplars to the WAL and send them over remote write.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Update example for exemplars, print data in a more obvious format.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Add metrics for remote write of exemplars.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Fix incorrect slices passed to send in remote write.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* We need to unregister the new metrics.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Address review comments
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Order of exemplar append vs write exemplar to WAL needs to change.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Several fixes to prevent sending uninitialized or incorrect samples with an exemplar. Fix dropping exemplar for missing series. Add tests for queue_manager sending exemplars
Signed-off-by: Martin Disibio <mdisibio@gmail.com>
* Store both samples and exemplars in the same timeseries buffer to remove the alloc when building final request, keep sub-slices in separate buffers for re-use
Signed-off-by: Martin Disibio <mdisibio@gmail.com>
* Condense sample/exemplar delivery tests to parameterized sub-tests
Signed-off-by: Martin Disibio <mdisibio@gmail.com>
* Rename test methods for clarity now that they also handle exemplars
Signed-off-by: Martin Disibio <mdisibio@gmail.com>
* Rename counter variable. Fix instances where metrics were not updated correctly
Signed-off-by: Martin Disibio <mdisibio@gmail.com>
* Add exemplars to LoadWAL benchmark
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* last exemplars timestamp metric needs to convert value to seconds with
ms precision
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Process exemplar records in a separate go routine when loading the WAL.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Address review comments related to clarifying comments and variable
names. Also refactor sample/exemplar to enqueue prompb types.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Regenerate types proto with comments, update protoc version again.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Put remote write of exemplars behind a feature flag.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Address some of Ganesh's review comments.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Move exemplar remote write feature flag to a config file field.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Address Bartek's review comments.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Don't allocate exemplar buffers in queue_manager if we're not going to
send exemplars over remote write.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Add ValidateExemplar function, validate exemplars when appending to head
and log them all to WAL before adding them to exemplar storage.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Address more reivew comments from Ganesh.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Add exemplar total label length check.
Signed-off-by: Callum Styan <callumstyan@gmail.com>
* Address a few last review comments
Signed-off-by: Callum Styan <callumstyan@gmail.com>
Co-authored-by: Martin Disibio <mdisibio@gmail.com>
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>
This commit adds `@ <timestamp>` modifier as per this design doc: https://docs.google.com/document/d/1uSbD3T2beM-iX4-Hp7V074bzBRiRNlqUdcWP6JTDQSs/edit.
An example query:
```
rate(process_cpu_seconds_total[1m])
and
topk(7, rate(process_cpu_seconds_total[1h] @ 1234))
```
which ranks based on last 1h rate and w.r.t. unix timestamp 1234 but actually plots the 1m rate.
Signed-off-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>
* promql: Removed global and add ability to have better interval for subqueries if not specified
## Changes
* Refactored tests for better hints testing
* Added various TODO in places to enhance.
* Moved DefaultEvalInterval global to opts with func(rangeMillis int64) int64 function instead
Motivation: At Thanos we would love to have better control over the subqueries step/interval.
This is important to choose proper resolution. I think having proper step also does not harm for
Prometheus and remote read users. Especially on stateless querier we do not know evaluation interval
and in fact putting global can be wrong to assume for Prometheus even.
I think ideally we could try to have at least 3 samples within the range, the same
way Prometheus UI and Grafana assumes.
Anyway this interfaces allows to decide on promQL user basis.
Open question: Is taking parent interval a smart move?
Motivation for removing global: I spent 1h fighting with:
=== RUN TestEvaluations
TestEvaluations: promql_test.go:31: unexpected error: error evaluating query "absent_over_time(rate(nonexistant[5m])[5m:])" (line 687): unexpected error: runtime error: integer divide by zero
--- FAIL: TestEvaluations (0.32s)
FAIL
At the end I found that this fails on most of the versions including this master if you run this test alone. If run together with many
other tests it passes. This is due to SetDefaultEvaluationInterval(1 * time.Minute)
in test that is ran before TestEvaluations. Thanks to globals (:
Let's fix it by dropping this global.
Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
* Added issue links for TODOs.
Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
* Removed irrelevant changes.
Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
time.Unix attaches the local timezone, which can then
leak out (e.g. in the alert json). While this is harmless,
we should be consistent.
Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
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>
Since we use ActiveQueryTracker to check for concurrency in
d992c36b3a it does not make sense to keep
the MaxConcurrent value as an option of the PromQL engine.
This pull request removes it from the PromQL engine options, sets the
max concurrent metric to -1 if there is no active query tracker, and use
the value of the active query tracker otherwise.
It removes dead code and also will inform people who import the promql
package that we made that change, as it breaks the EngineOpts struct.
Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
* Added query logging for prometheus.
Options added:
1) active.queries.filepath: Filename where queries will be recorded
2) active.queries.filesize: Size of the file where queries will be recorded.
Functionality added:
All active queries are now logged in a file. If prometheus crashes unexpectedly, these queries are also printed out on stdout in the rerun.
Queries are written concurrently to an mmaped file, and removed once they are done. Their positions in the file are reused. They are written in json format. However, due to dynamic nature of application, the json has an extra comma after the last query, and is missing an ending ']'. There may also null bytes in the tail of file.
Signed-off-by: Advait Bhatwadekar <advait123@ymail.com>
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>
