prometheus

Commit Graph

Author	SHA1	Message	Date
Filip Petkovski	1f69dcfa6b	Fix reusing float histograms In https://github.com/prometheus/prometheus/pull/13276 we started reusing float histogram objects to reduce allocations in PromQL. That PR introduces a bug where histogram pointers gets copied to the beginning of the histograms slice, but are still kept in the end of the slice. When a new histogram is read into the last element, it can overwrite a previous element because the pointer is the same. This commit fixes the issue by moving outdated points to the end of the slice so that we don't end up with duplicate pointers in the same buffer. In other words, the slice gets rotated so that old objects can get reused. Signed-off-by: Filip Petkovski <filip.petkovsky@gmail.com>	12 months ago
Fiona Liao	5bee0cfce2	Change `ChunkReader.Chunk()` to `ChunkOrIterable()` 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>	1 year ago
Justin Lei	8ef7dfdeeb	Add a chunk size limit in bytes (#12054 ) Add a chunk size limit in bytes This creates a hard cap for XOR chunks of 1024 bytes. The limit for histogram chunk is also 1024 bytes, but it is a soft limit as a histogram has a dynamic size, and even a single one could be larger than 1024 bytes. This also avoids cutting new histogram chunks if the existing chunk has fewer than 10 histograms yet. In that way, we are accepting "jumbo chunks" in order to have at least 10 histograms in a chunk, allowing compression to kick in. Signed-off-by: Justin Lei <justin.lei@grafana.com>	1 year ago
beorn7	aa82fe198f	tsdb: Fix histogram validation So far, `ValidateHistogram` would not detect if the count did not include the count in the zero bucket. This commit fixes the problem and updates all the tests that have been undetected offenders so far. Note that this problem would only ever create false negatives, so we never falsely rejected to store a histogram because of it. On the other hand, `ValidateFloatHistogram` has been to strict with the count being at least as large as the sum of the counts in all the buckets. Float precision issues could create false positives here, see products of PromQL evaluations, it's actually quite hard to put an upper limit no the floating point imprecision. Users could produce the weirdest expressions, maxing out float precision problems. Therefore, this commit simply removes that particular check from `ValidateFloatHistogram`. Signed-off-by: beorn7 <beorn@grafana.com>	1 year ago
George Krajcsovits	92d6980360	Fix populateWithDelChunkSeriesIterator and gauge histograms (#12330 ) Use AppendableGauge to detect corrupt chunk with gauge histograms. Detect if first sample is a gauge but the chunk is not set up to contain gauge histograms. Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com> Signed-off-by: George Krajcsovits <krajorama@users.noreply.github.com>	2 years ago
Justin Lei	af1d9e01c7	Refactor tsdbutil for tests/native histograms (#11948 ) * Add float histograms to ChunkFromSamplesGeneric Signed-off-by: Justin Lei <justin.lei@grafana.com> * Add GenerateSamples functions to tsdbutil Signed-off-by: Justin Lei <justin.lei@grafana.com> PR responses Signed-off-by: Justin Lei <justin.lei@grafana.com> --------- Signed-off-by: Justin Lei <justin.lei@grafana.com>	2 years ago

6 Commits (d5f68872943062d4535ef8cffc53b4613a541d11)