[PATCH] D133153: [support] Prepare TimeProfiler for cross-thread support

Joe Loser via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Thu Sep 15 08:49:45 PDT 2022 

jloser accepted this revision.
jloser added a comment.

In D133153#3792269 <https://reviews.llvm.org/D133153#3792269>, @russell.gallop wrote:

>> @russell.gallop can you still repro a regression with the current patch?
>
> Sorry to take a while to reply.
>
> I rebuilt with Diff 460060 applied to 40ab7875f8ccb8d1b0166bf91475fc4d662cffe9 <https://reviews.llvm.org/rG40ab7875f8ccb8d1b0166bf91475fc4d662cffe9> and yes, I do still see a build performance impact with -ftime-trace. I reproduced this building SemaExpr.cpp from a stage2 build so this should be something that you can reproduce.
>
> In spite of the warning about statistical outliers (it was a pretty quiet PC), there is no overlap between the range of times with and without -ftime-trace so it's not just one or two samples causing this.
>
>   f:\git\llvm-project\stage2>%USERPROFILE%\bin\hyperfine -w 1 -m 10 "F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp" "F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp -ftime-trace"
>   Benchmark #1: F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp
>     Time (mean ± σ):     42.646 s ±  0.417 s    [User: 1.3 ms, System: 13.0 ms]
>     Range (min … max):   41.783 s … 43.535 s    10 runs
>   
>     Warning: Statistical outliers were detected. Consider re-running this benchmark on a quiet PC without any interferences from other programs. It might help to use the '--warmup' or '--prepare' options.
>   
>   Benchmark #2: F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp -ftime-trace
>     Time (mean ± σ):     46.308 s ±  1.108 s    [User: 3.9 ms, System: 9.9 ms]
>     Range (min … max):   44.930 s … 49.074 s    10 runs
>   
>   Summary
>     'F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp' ran
>       1.09 ± 0.03 times faster than 'F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp -ftime-trace'
>
> And without this patch it's just 1%.
>
>   f:\git\llvm-project\stage2>%USERPROFILE%\bin\hyperfine -w 1 -m 10 "F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp" "F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp -ftime-trace"
>   Benchmark #1: F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp
>     Time (mean ± σ):     40.761 s ±  1.346 s    [User: 1.2 ms, System: 7.4 ms]
>     Range (min … max):   38.188 s … 42.256 s    10 runs
>   
>   Benchmark #2: F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp -ftime-trace
>     Time (mean ± σ):     41.162 s ±  0.319 s    [User: 2.5 ms, System: 8.7 ms]
>     Range (min … max):   40.750 s … 41.845 s    10 runs
>   
>   Summary
>     'F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp' ran
>       1.01 ± 0.03 times faster than 'F:\git\llvm-project\stage1\bin\clang-cl.exe  /nologo -TP -DGTEST_HAS_RTTI=0 -DUNICODE -D_CRT_NONSTDC_NO_DEPRECATE -D_CRT_NONSTDC_NO_WARNINGS -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -D_GNU_SOURCE -D_HAS_EXCEPTIONS=0 -D_SCL_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_WARNINGS -D_UNICODE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -Itools\clang\lib\Sema -IF:\git\llvm-project\clang\lib\Sema -IF:\git\llvm-project\clang\include -Itools\clang\include -Iinclude -IF:\git\llvm-project\llvm\include -Wno-nonportable-include-path /Zc:inline /Zc:__cplusplus /Oi /Brepro /bigobj /permissive- /W4  -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported /Gw /MT /O2 /Ob2 /DNDEBUG    /EHs-c- /GR- -std:c++17 /Fotools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\SemaExpr.cpp.obj /Fdtools\clang\lib\Sema\CMakeFiles\obj.clangSema.dir\ -c F:\git\llvm-project\clang\lib\Sema\SemaExpr.cpp -ftime-trace'
>
> Sorry I don't have time to look into this in more depth, but it is a cause for concern that we might be losing a nice property of -ftime-trace.
>
> Apart from this I'm happy with the patch.
>
> (And many apologies in advance if it's something I'm doing wrong here! I'd be interested if anyone else can reproduce this on SemaExpr. If it's just me then I'd suggest not blocking this patch landing due to this.)

@mbs-modular - it'd be interesting to see if this is something you can repro on Linux with a stage2 build.

Other than that, this patch LGTM.  If you need me or someone else to commit this on your behalf, can you please provide the email address you'd like to use for commit attribution?


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