ydb/library/cpp/yt/misc/guid.cpp, branch CLI_2.32.0Mirror of YDB github reposhttps://code.mastervirt.ru/ydb/atom?h=CLI_2.32.02026-06-12T21:17:12ZSpeed up NYT::Format2026-06-12T21:17:12Zbabenkobabenko@yandex-team.com2026-06-12T20:53:40Zurn:sha1:42e4b751702f065de932ef765bc6948c5e7d1e4b
Profile-driven optimizations of the `Format` hot path, benchmarked against a representative master debug log (structured `"Key: %v"` messages dominated by GUIDs, strings, integers, bools and durations). Median improvements of ~15-20% across the workload, measured on a dedicated host.
Changes:
- `string_builder`: use `resize_uninitialized` in `DoReserve` to avoid zero-filling the buffer on every `Format` call.
- `format`: replace the per-argument `memchr` (`spec.Contains('n')`) with an inline scan, force-inline `RunFormatterAt`, and add a `FormatString` fast path for the common plain `%v` / empty spec.
- `guid`: rewrite `WriteGuidToBuffer` using a `clz`-derived digit count and a back-to-front fill instead of the per-magnitude branch cascade (cut from ~26% to ~12% of a GUID-heavy line). Validated against an `%x` reference over 2M random GUIDs plus edge cases.
Also adds `library/cpp/yt/string/benchmark` to track `Format` performance.
### Benchmarks
Median ns/op (lower is better), pinned core on a dedicated Xeon E5-2650 v2, 9x1s repetitions. See `library/cpp/yt/string/benchmark`.
| Benchmark | What it formats | Before | After | Speedup |
| --- | --- | ---: | ---: | ---: |
| `ManyMixedArgs` | ~18 args: GUIDs, strings, duration, ints | 1030 | 833 | -19% |
| `StringAndTwoGuids` | literal prefix + two GUIDs | 233 | 185 | -21% |
| `IntAndGuid` | one int + one GUID | 205 | 179 | -13% |
| `ManyInts` | six integers | 389 | 340 | -13% |
| `Guid` | a single GUID | 156 | 131 | -16% |
| `String` | a single string | 139 | 104 | -25% |
| `Int` | a single integer | 142 | 120 | -15% |
| `NoArgs` | a literal with no arguments | 88.8 | 85.7 | -3% |
commit_hash:ce9957a06c3ff28b2889aa65fbbddf4ca444f9fe
YT-22593: More trivial TString->std::string migrations2025-02-22T14:48:29Zbabenkobabenko@yandex-team.com2025-02-22T14:28:25Zurn:sha1:59afaa0cb7cd89146dd10f5446256afcce33bd0e
[nodiff:runtime]
commit_hash:1ba799aed1703ab7c6304b6da7090b3337f768dd
YT-21233: Remove TSimpleException and teach TCompositeException storing simple attributes2024-03-28T06:58:54Zarkady-e1ppaarkady-e1ppa@yandex-team.com2024-03-28T06:47:08Zurn:sha1:48212452a70da88a5e4b814979dd82f22379801f
Expand the CompositeException
9a10ec65bfc1df854e03bb3a4d8d0a0c0e4a3a5d
More TGuid helpers2023-11-25T14:31:15Zbabenkobabenko@yandex-team.com2023-11-25T14:05:18Zurn:sha1:ef0f7daa4fdd7a8866514cdd37dafdb5ceaa9724Restoring authorship annotation for <babenko@yandex-team.ru>. Commit 2 of 2.2022-02-10T13:49:19Zbabenkobabenko@yandex-team.ru2022-02-10T13:49:19Zurn:sha1:f31097c96270919a1f49360bdaaa69ea4f3fefabRestoring authorship annotation for <babenko@yandex-team.ru>. Commit 1 of 2.2022-02-10T13:49:19Zbabenkobabenko@yandex-team.ru2022-02-10T13:49:19Zurn:sha1:cec37806d8847aa3db53bafc9e251d4aaf325c12Restoring authorship annotation for <ignat@yandex-team.ru>. Commit 2 of 2.2022-02-10T13:48:20Zignatignat@yandex-team.ru2022-02-10T13:48:20Zurn:sha1:12d7840a194f4a6e4ea77a405f980074cf43e942Restoring authorship annotation for <ignat@yandex-team.ru>. Commit 1 of 2.2022-02-10T13:48:20Zignatignat@yandex-team.ru2022-02-10T13:48:20Zurn:sha1:c8b279dd21ddcb47e755028d81281f113a0f4a11Restoring authorship annotation for <max42@yandex-team.ru>. Commit 2 of 2.2022-02-10T13:47:51Zmax42max42@yandex-team.ru2022-02-10T13:47:51Zurn:sha1:884333bd8b9068bc6b852b948e9d8f23fd393ab7Restoring authorship annotation for <max42@yandex-team.ru>. Commit 1 of 2.2022-02-10T13:47:51Zmax42max42@yandex-team.ru2022-02-10T13:47:51Zurn:sha1:9988f7c537b40605e1a0aaae2977d5f540425b83