Add build flag to enable PGO for Engine build.

[Nobutarou]

My idea is
1st, build with '-addflag="-O2 -fprofile-generate''.
2nd, run a target model to collect profile.
3rd, build with '-addflag="-O2 -fprofile-use"'.

However, the 1st build does not succeed. A lot of the following errors happen,

/bin/ld: CMakeFiles/engine_linux64_gf_ompi.dir/source/coupling/rad2rad/rad2rad_c.c.o: warning: relocation against `__gcov_time_profiler_counter' in read-only section `.text'
/bin/ld: CMakeFiles/engine_linux64_gf_ompi.dir/aur/OpenRadioss/common_source/comm/compress_nnz.F.o: in function `compress_r_nnz_':
/aur/OpenRadioss/common_source/comm/compress_nnz.F:153: undefined reference to `__gcov_indirect_call'

I attach the log file, too.
engine_build.log

[Nobutarou]

I can build.

For the 1st step, I missed -lgcov. Thus, I add it to addflag,

-addflag="-O2 -fprofile-generate -lgcov''

and I need to pass '-lgcov' to the linker. I have to modify <openradioss_root>/engine/cbuild_linux64_gf_ompi/CMakeFiles/engine_linux64_gf_ompi.dir/link.txt to

gfortran   -fopenmp  -ldl -lrt -lstdc++    @CMakeFiles/engine_linux64_gf_ompi.dir/objects1.rsp @CMakeFiles/engine_linux64_gf_ompi.dir/objects2.rsp -o engine_linux64_gf_ompi  -lrt -L/opt/openmpi/lib -lmpi -lmpi_mpifh -ldl -Wunused-function -lstdc++ -lgcov

I don't know what file generates link.txt. Thus, I just modify and disallow removal.

[laurent-altr]

Hi @Nobutarou,

For the engine, you can add the compilation flags into the file cmake_linux64_gf.txt.

Thank you!

[Nobutarou]

I find CMAKE_EXE_LINKER_FLAGS in the file. Helpful.
Thank you.

[zamazan4ik]

@Nobutarou excuse me for the necroposting. I see you built the project with PGO. Could you please share the benchmark results, how many in performance did you win after enabling PGO for OpenRadioss?

I am interested in this information since I collect all benchmarks about PGO in my PGO repo: https://github.com/zamazan4ik/awesome-pgo

Thank you!

[Nobutarou]

Hi, I don't have the logs but have a memo. According to the memo, CPU: Ryzen 3 Pro 4350G (4 cores 8 threads) Ram: 16GB OS: Arch Linux I use this input model, and run three times both for normal build and PGO build to measure their elapsed time, https://openradioss.atlassian.net/wiki/spaces/OPENRADIOSS/pages/11075585/Bumper+Beam Here is the result, 15% faster. | trial |normal build[s] | PGO[s] | speed up | | --- | --- | --- | --- | |1st | 374.45 | 323.69 | 1.16 | |2nd | 373.87 | 324.11 |1.15 | | 3rd | 374.43 | 323.42 | 1.16 | For normal build, I use just "-O2". For PGO build, I first use "-O2 -fprofile-generate -lgcov" to correct the profile and re-build with "-O2 -fprofile-use" Thanks, Nobuyuki 2024年7月6日(土) 19:16 Alexander Zaitsev ***@***.***>:

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@Nobutarou <https://github.com/Nobutarou> excuse me for the necroposting. I see you built the project with PGO. Could you please share the benchmark results, how many in performance did you win after enabling PGO for OpenRadioss? I am interested in this information since I collect all benchmarks about PGO in my PGO repo: https://github.com/zamazan4ik/awesome-pgo Thank you! — Reply to this email directly, view it on GitHub <#393 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAKOKXZQ5SHZY5VDLX2FVM3ZK67W3AVCNFSM6AAAAABKOJYFVWVHI2DSMVQWIX3LMV43SRDJONRXK43TNFXW4Q3PNVWWK3TUHM4TSNZUGA3TI> . You are receiving this because you were mentioned.Message ID: ***@***.***>