promql: force mmap of head chunks in BenchmarkRangeQuery#12755
Merged
bboreham merged 1 commit intoprometheus:mainfrom Aug 26, 2023
Merged
promql: force mmap of head chunks in BenchmarkRangeQuery#12755bboreham merged 1 commit intoprometheus:mainfrom
bboreham merged 1 commit intoprometheus:mainfrom
Conversation
Otherwise we have a highly unusual situation of over 100 chunks in the headChunks list of each series, which heavily skews performance. Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
SuperQ
approved these changes
Aug 26, 2023
This was referenced Aug 26, 2023
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Otherwise we have a highly unusual situation of over 100 chunks in the headChunks list of each series, which heavily skews performance.
Example before and after:
This was a highly confusing bug to track down, because
DB.run()does callmmapHeadChunksevery 1 minute, so depending on what benchmarks you run you can get the faster performance.To avoid
Compact()disrupting performance every minute I disabled auto-compacting. However this previously ran after every commit, so I callCompact()once all the data is ready.