Query frontend: Add benchmarks for labels codec and query range codec

[matej-g]

• I added CHANGELOG entry for this change.
• Change is not relevant to the end user.

Changes

As a part of working on query frontend performance related task (#4571), I'm adding benchmarks to query frontend packages for codecs.

Results:

queryfrontend ❯ go test -bench=.                                                                     query-frontend-benchmarks
goos: linux
goarch: amd64
pkg: github.com/thanos-io/thanos/pkg/queryfrontend
cpu: Intel(R) Core(TM) i7-9850H CPU @ 2.60GHz
BenchmarkLabelsCodecEncodeAndDecodeRequest/SeriesRequest-12               217172              5070 ns/op            3496 B/op         44 allocs/op
BenchmarkLabelsCodecEncodeAndDecodeRequest/LabelsRequest-12               165806              7023 ns/op            3937 B/op         57 allocs/op
BenchmarkLabelsCodecDecodeResponse/SeriesResponse-12                      335694              3269 ns/op            2056 B/op         34 allocs/op
BenchmarkLabelsCodecDecodeResponse/SeriesResponseWithHeaders-12           279236              3689 ns/op            2528 B/op         39 allocs/op
BenchmarkLabelsCodecDecodeResponse/LabelsResponse-12                      569709              2272 ns/op            1328 B/op         20 allocs/op
BenchmarkLabelsCodecDecodeResponse/LabelsResponseWithHeaders-12           468223              2578 ns/op            1800 B/op         25 allocs/op
BenchmarkLabelsCodecMergeResponses_1/SeriesResponses-12                  1980333               635.0 ns/op           368 B/op         10 allocs/op
BenchmarkLabelsCodecMergeResponses_1/LabelsResponses-12                 460894840                2.546 ns/op           0 B/op          0 allocs/op
BenchmarkLabelsCodecMergeResponses_10/SeriesResponses-12                  216445              5103 ns/op            2929 B/op         68 allocs/op
BenchmarkLabelsCodecMergeResponses_10/LabelsResponses-12                  659503              1676 ns/op             593 B/op          4 allocs/op
BenchmarkLabelsCodecMergeResponses_100/SeriesResponses-12                  18146             63734 ns/op           31966 B/op        618 allocs/op
BenchmarkLabelsCodecMergeResponses_100/LabelsResponses-12                  51276             22847 ns/op            7151 B/op         11 allocs/op
BenchmarkLabelsCodecMergeResponses_1000/SeriesResponses-12                  1598            699492 ns/op          342276 B/op       6046 allocs/op
BenchmarkLabelsCodecMergeResponses_1000/LabelsResponses-12                  3666            298388 ns/op          101812 B/op         36 allocs/op
BenchmarkQueryRangeCodecEncodeAndDecodeRequest-12                         169071              6655 ns/op            4000 B/op         58 allocs/op
PASS
ok      github.com/thanos-io/thanos/pkg/queryfrontend   19.568s

Verification

Benchmarks ran

[yeya24]

LGTM for the benchmark tests.
For the performance issue of query frontend, what's next and what's the conclusion from the benchmark results?

[GiedriusS]

Looks good, just one nit

[matej-g]

LGTM for the benchmark tests. For the performance issue of query frontend, what's next and what's the conclusion from the benchmark results?

You can read the conclusion at #4571 (comment) - tl;dr: I could not confirm any performance issue despite the initial reports we received. The sentiment was that it would still be nice to have some benchmarks for query frontend, but for now the results look in order to me.

[yeya24]

LGTM