thevar1able/ClickHouse
1
0
Fork 0
mirror of https://github.com/ClickHouse/ClickHouse.git synced 2024-11-23 16:12:01 +00:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #57377 from zamazan4ik/master

Browse Source 
doc: update profile-guided-optimization.md
This commit is contained in:
robot-ch-test-poll1 2023-11-30 12:55:27 +01:00 committed by GitHub
commit 192362d2fb
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
docs/en/operations/optimizing-performance/profile-guided-optimization.md
View File

@ -16,9 +16,9 @@ More information about PGO in ClickHouse you can read in the corresponding GitHu
There are two major kinds of PGO: [Instrumentation](https://clang.llvm.org/docs/UsersManual.html#using-sampling-profilers) and [Sampling](https://clang.llvm.org/docs/UsersManual.html#using-sampling-profilers) (also known as AutoFDO). In this guide is described the Instrumentation PGO with ClickHouse.
1. Build ClickHouse in Instrumented mode. In Clang it can be done via passing `-fprofile-instr-generate` option to `CXXFLAGS`.
1. Build ClickHouse in Instrumented mode. In Clang it can be done via passing `-fprofile-generate` option to `CXXFLAGS`.
2. Run instrumented ClickHouse on a sample workload. Here you need to use your usual workload. One of the approaches could be using [ClickBench](https://github.com/ClickHouse/ClickBench) as a sample workload. ClickHouse in the instrumentation mode could work slowly so be ready for that and do not run instrumented ClickHouse in performance-critical environments.
3. Recompile ClickHouse once again with `-fprofile-instr-use` compiler flags and profiles that are collected from the previous step.
3. Recompile ClickHouse once again with `-fprofile-use` compiler flags and profiles that are collected from the previous step.
A more detailed guide on how to apply PGO is in the Clang [documentation](https://clang.llvm.org/docs/UsersManual.html#profile-guided-optimization).