ydb/library/cpp/yt/string, 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: Add formatter for all protobuf enums2026-06-02T10:59:36Zgrigminakovgrigminakov@yandex-team.com2026-06-02T08:55:51Zurn:sha1:3b859ddc8d5eee908953aa0a217e448933ffc2af
commit_hash:58bf07dcff4aac728a67e0607d2c3b49ad1feef1
Remove excess blank line2026-05-19T01:15:02Zpechatnovpechatnov@yandex-team.com2026-05-19T00:48:45Zurn:sha1:e324708cc3d0cf8fe8e3f192da6a1d1f93c2bdc5
commit_hash:fff41cdbc1400a312067a6517c334440404c662b
YT-26137: Drop indicies in multicell manager2026-05-12T00:44:14Zcherepashkacherepashka@yandex-team.com2026-05-12T00:24:37Zurn:sha1:2772dbbb657803d9e96f552b13993740a1c280f9
* Changelog entry
Type: feature
Component: master
Drop indicies in multicell manager
commit_hash:692a550606183f6a8cb93425761911bbba09dceb
YT-27951: Use truncated string view to limit query length in traces2026-04-23T08:16:41Zosidorkinosidorkin@yandex-team.com2026-04-23T07:46:30Zurn:sha1:3eafe425787c0c3d6b9388faca597c1ab1a978b0
commit_hash:84610a30b17de408952f5c68dbc32b18b753b247
YT-18571: Add format string checks to TStringBuilderBase::AppendFormat; also fix some releaved issues2026-04-22T07:08:46Zbabenkobabenko@yandex-team.com2026-04-22T06:41:38Zurn:sha1:70410f21980c0632b4746ec75cd9ba5762fc109a
commit_hash:dd15e713a6a83c8a14f1df2f011fa06f189f4a00
YT-27951: Add special formatter for truncated string2026-04-20T19:34:00Zosidorkinosidorkin@yandex-team.com2026-04-20T14:41:31Zurn:sha1:bac55b8485b68056b30a4d51ad60443a945c406f
commit_hash:88bc9543595f9b630942d63aa1c3aee154056e92
Fix some use-after-move bugs2026-04-17T13:37:33Zpavookpavook@yandex-team.com2026-04-17T12:40:13Zurn:sha1:70edb604e93a313f36e434fd25b312527d59f361
commit_hash:4bc357937e76b2b082671bb0f67ac3012ee4dbca
Add suggestions on enum parse error2026-03-26T08:00:16Zpechatnovpechatnov@yandex-team.com2026-03-26T07:11:59Zurn:sha1:9852998440dcaa3eec11377553e996ff9852bb4e
commit_hash:3b7f35f613737aa92f473877e8b24782f7dfcd2a
[yt/string] bit-independent version of FormatPointerValue2026-03-06T07:40:38Zvaskovasko@yandex-team.com2026-03-06T07:18:45Zurn:sha1:39ae7ca20aaff68379747bae5db37b9d446cf9ee
commit_hash:77b05e63c7d030fccb8d13d83f5e9dc4f660e19d