Always return unknown hint for first sample in non-gauge histogram chunk
---------
Signed-off-by: Fiona Liao <fiona.liao@grafana.com>
Co-authored-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
When handling recoded histogram chunks the min time of the chunk is
updated by mistake. It should only update when the chunk is completely
new.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Two Appenders race when creating a series with a native histogram
as the memSeries will be common and the lastHistogram field is written
without lock.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Check if headQuerier is nil before trying to use it.
* TestQueryOOOHeadDuringTruncate: unit test to check query during truncate
Regression test for #14822
* Simulate race between query and Compact()
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
This was part of #14525 which was reverted.
I still think that having this benchmark committed in to the repo is
useful.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Fix appendable: check whether last val was a histogram
When appending a float, we were checking whether lastValue was equal to
current value, but we didn't check whether last value was a float value.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* Pass affected labels to MemPostings.Delete
As suggested by @bboreham, we can track the labels of the deleted series
and avoid iterating through all the label/value combinations.
This looks much faster on the MemPostings.Delete call. We don't have a
benchmark on stripeSeries.gc() where we'll pay the price of iterating
the labels of each one of the deleted series.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
* TSDB: Don't compact the head block when empty
Don't compact the Head block if there have not yet been any samples
appended.
Previously, the logic for determining if the head should be compacted
relied on the default values for min and max time and integer overflow
when they were checked in `Head.compactable()`. The check in
`Head.compactable()` effectively did `math.MinInt64 - math.MaxInt64`
which overflowed and wrapped to `1`. Since `1` is less than `1.5`
times the chunk range, compaction did not happen. This was the correct
behavior but relying on overflow wrapping is surprising.
This change add a method for checking if the min and max time for the
head is unset and uses it to short-circuit compaction in that case.
It also replaces several explicit checks for the default value to
determine if the head has not yet had any samples added.
Signed-off-by: Nick Pillitteri <nick.pillitteri@grafana.com>
This PR is a reference implementation of the proposal described in #10420.
In addition to what described in #10420, in this PR I've introduced labels.StableHash(). The idea is to offer an hashing function which doesn't change over time, and that's used by query sharding in order to get a stable behaviour over time. The implementation of labels.StableHash() is the hashing function used by Prometheus before stringlabels, and what's used by Grafana Mimir for query sharding (because built before stringlabels was a thing).
Follow up work
As mentioned in #10420, if this PR is accepted I'm also open to upload another foundamental piece used by Grafana Mimir query sharding to accelerate the query execution: an optional, configurable and fast in-memory cache for the series hashes.
Signed-off-by: Marco Pracucci <marco@pracucci.com>
Add test case to TestHeadLabelValuesWithMatchers, while fixing a couple
of typos in other test cases. Also enclosing some implicit sub-tests in a
`t.Run` call to make them explicitly sub-tests.
Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>
Optimize histogram iterators
Histogram iterators allocate new objects in the AtHistogram and
AtFloatHistogram methods, which makes calculating rates over long
ranges expensive.
In #13215 we allowed an existing object to be reused
when converting an integer histogram to a float histogram. This commit follows
the same idea and allows injecting an existing object in the AtHistogram and
AtFloatHistogram methods. When the injected value is nil, iterators allocate
new histograms, otherwise they populate and return the injected object.
The commit also adds a CopyTo method to Histogram and FloatHistogram which
is used in the BufferedIterator to overwrite items in the ring instead of making
new copies.
Note that a specialized HPoint pool is needed for all of this to work
(`matrixSelectorHPool`).
---------
Signed-off-by: Filip Petkovski <filip.petkovsky@gmail.com>
Co-authored-by: George Krajcsovits <krajorama@users.noreply.github.com>
* Append created timestamps.
Signed-off-by: Arthur Silva Sens <arthur.sens@coralogix.com>
* Log when created timestamps are ignored
Signed-off-by: Arthur Silva Sens <arthur.sens@coralogix.com>
* Proposed changes to Append CT PR.
Changes:
* Changed textparse Parser interface for consistency and robustness.
* Changed CT interface to be more explicit and handle validation.
* Simplified test, change scrapeManager to allow testability.
* Added TODOs.
Signed-off-by: bwplotka <bwplotka@gmail.com>
* Updates.
Signed-off-by: bwplotka <bwplotka@gmail.com>
* Addressed comments.
Signed-off-by: bwplotka <bwplotka@gmail.com>
* Refactor head_appender test
Signed-off-by: Arthur Silva Sens <arthur.sens@coralogix.com>
* Fix linter issues
Signed-off-by: Arthur Silva Sens <arthur.sens@coralogix.com>
* Use model.Sample in head appender test
Signed-off-by: Arthur Silva Sens <arthur.sens@coralogix.com>
---------
Signed-off-by: Arthur Silva Sens <arthur.sens@coralogix.com>
Signed-off-by: bwplotka <bwplotka@gmail.com>
Co-authored-by: bwplotka <bwplotka@gmail.com>
The 'ToFloat' method on integer histograms currently allocates new memory
each time it is called.
This commit adds an optional *FloatHistogram parameter that can be used
to reuse span and bucket slices. It is up to the caller to make sure the
input float histogram is not used anymore after the call.
Signed-off-by: Filip Petkovski <filip.petkovsky@gmail.com>
* Fix tsdb.stripeSeries.gc so it handles conflicts properly
tsdb.stripeSeries.gc needs to prune seriesHashmap.conflicts first,
otherwise seriesHashmap replaces the unique field with the first among
the conflicts. Also add regression test.
Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>
* TestStripeSeries_gc: Support stringlabels, don't use internals
Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>
---------
Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>
The ChunkReader interface's Chunk() has been changed to ChunkOrIterable().
This is a precursor to OOO native histogram support - with OOO native histograms, the chunks.Meta passed to Chunk() can result in multiple chunks being returned rather than just a single chunk (e.g. if oooMergedChunk has a counter reset in the middle).
To support this, ChunkOrIterable() requires either a single chunk or an iterable to be returned. If an iterable is returned, the caller has the responsibility of converting the samples from the iterable into possibly multiple chunks. The OOOHeadChunkReader now returns an iterable rather than a chunk to prepare for the native histograms case. Also as a beneficial side effect, oooMergedChunk and boundedChunk has been simplified as they only need to implement the Iterable interface now, not the full Chunk interface.
---------
Signed-off-by: Fiona Liao <fiona.y.liao@gmail.com>
Co-authored-by: George Krajcsovits <krajorama@users.noreply.github.com>
* Fix tsdb.seriesHashmap.set by making receiver a pointer
The method tsdb.seriesHashmap.set currently doesn't set the conflicts
field properly, due to the receiver being a non-pointer. Fix by turning
the receiver into a pointer, and add a corresponding regression test.
Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>
* Fix panic during tsdb Commit
Fixes the following
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0x19deb45]
goroutine 651118930 [running]:
github.com/prometheus/prometheus/tsdb.(*headAppender).Commit(0xc19100f7c0)
/drone/src/vendor/github.com/prometheus/prometheus/tsdb/head_append.go:855 +0x245
github.com/prometheus/prometheus/tsdb.dbAppender.Commit({{0x35bd6f0?, 0xc19100f7c0?}, 0xc000fa4c00?})
/drone/src/vendor/github.com/prometheus/prometheus/tsdb/db.go:1159 +0x2f
We theorize that the panic happened due the the series referenced by the
exemplar being removed between AppendExemplar and Commit due to being idle.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
When samples are committed in the head, they are also written to the WAL.
The order of WAL records should be sample then exemplar, but this was
not the case for native histogram samples. This PR fixes that.
The problem with the wrong order is that remote write reads the WAL and
sends the recorded timeseries in the WAL order, which means exemplars
arrived before histogram samples. If the receiving side is Prometheus
TSDB and the series has not existed before then the exemplar does not
currently create the series. Which means the exemplar is rejected and lost.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
