Follow up on https://github.com/prometheus/prometheus/pull/14096
As promised, I bring a benchmark, which shows a very small improvement
if context is checked every 128 iterations of label instead of every
100.
It's much easier for a computer to check modulo 128 than modulo 100.
This is a very small 0-2% improvement but I'd say this is one of the
hottest paths of the app so this is still relevant.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
defaultStatsRenderer->DefaultStatsRenderer
Add short docstrings.
I'd like to use the stats renderer to peek at the statistics in
https://github.com/grafana/mimir/pull/7966
However I cannot call the original function without this export afterwards.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Followup to #14096
Unfortunately the previous PR introduced this bug by not releasing the
lock before returning.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
* tsdb: check for context cancel before regex matching postings
Regex matching can be heavy if the regex takes a lot of cycles to
evaluate and we can get stuck evaluating postings for a long time
without this fix. The constant checkContextEveryNIterations=100
may be changed later.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
On Windows, Go will sleep 15ms if you ask for less. TestAsyncRuleEvaluation
compares actual delay to the nominal time, so using 15ms should work
better on Windows, and be hardly noticeable elsewhere.
Signed-off-by: Bryan Boreham <bjboreham@gmail.com>
[ENHANCEMENT] Relabeling: small speed-up of hashmod
Code optimization: The relabel operation is used very frequently, and strconv.FormatInt() with better performance should be used.
This replaces the custom `moreThanOneRune` function with the standard
`utf8.DecodeRuneInString(s)` that can be used to figure out the size of
the first rune.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
This adds some more test cases for unicode values, and also a benchmark
for zeroOrOneCharacterStringMatcher.Matches()
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
Add method `PostingsForLabelMatching` to `tsdb.IndexReader`, to obtain postings for labels with a certain name and values accepted by a provided callback, and use it from `tsdb.PostingsForMatchers`.
The intention is to optimize regexp matcher paths, especially not having to load all label values before matching on them.
Plus tests, and refactor some `tsdb/index.Reader` methods.
Benchmarking shows memory reduction up to ~100%, and speedup of up to ~50%.
Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>
Co-authored-by: Bartlomiej Plotka <bwplotka@gmail.com>
When the label name of a matcher contains non-standard characters, like
a dot, or starts with a digit, it should be quoted.
If it's not quoted, then `VectorSelector.String()` isn't a valid PromQL.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
The function `rangeEvalTimestampFunctionOverVectorSelector` appeared to be checking histogram size, however the value it used was always 0 due to subtle variable shadowing.
However we don't need to pass sample values to the `timestamp` function, since the latter only cares about timestamps. This also affects peak sample count in statistics, since we are no longer copying histogram samples.
Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>
