Hi all, I attended Shachar's talk yesterday for Herzelinux about Profile-Guided Optimisations in gcc, etc. The talk was very interesting, but the focus of the talk was only covered for a very small part of it.
In any case, Shachar mentioned that he tried to test the results of Profile Guided Optimisations (PGO) on three programs and was able to build only one with them. When I returned home I was anxious to try out the PGO with Freecell Solver. I had to fix the "Makefile.gnu" that came with the distribution because it had some bugs that caused gcc to yell at me (I missed some flags in the linking stage). But I got it working. Now with the following steps: On https://svn.berlios.de/svnroot/repos/fc-solve/trunk/fc-solve/source: 1. make -f Makefile.gnu clean . 2. $ cat profile-guided-optimisations.bash #!/bin/bash make -f Makefile.gnu FREECELL_ONLY=1 \ CFLAGS='-DFCS_FREECELL_ONLY=1 -O3 -Wall -Werror=implicit-function- declaration -march=pentium4 -fomit-frame-pointer -fprofile-generate -fPIC' \ # END_LFLAGS='-lm -lgcov -static-libgcc' \ # CREATE_SHARED=' 3. bash profile-guided-optimisations.bash 4. ./freecell-solver-range-parallel-solve 1 32000 500 -l gi | tee dump (The actual profiling). 5. $ cat profile-guided-optimisations-stage2.bash #!/bin/bash cat profile-guided-optimisations.bash | perl -pe 's/-fprofile-generate/-fprofile-use/' | bash 6. bash profile-guided-optimisations-stage2.bash 7. ./freecell-solver-range-parallel-solve 1 32000 500 -l gi | tee dump Benchmarking. ----------- Then: 1. With profile guided optimisations, the benchmark ran at 126.168390989304 seconds. 2. Without profile guided optimisations, (only the other flags), the benchmark ran at 124.147925853729 seconds. So its seems PGO have made things somewhat worse. 3. I should note that a previous benchmark that I ran, ran at: {{{{{{{{{{ Trunk (r1755) with "./Tatzer -l p4b" after running strip on the binaries and regular (non-threaded) range-solver "-l gi": (gcc-4.4.0) 122.316657066345s }}}}}}}}}} I don't know what made it slightly slower now. All of the benchmarks were conducted while running only IceWM on top of my Mandriva Cooker system. Regards, Shlomi Fish -- ----------------------------------------------------------------- Shlomi Fish http://www.shlomifish.org/ "The Human Hacking Field Guide" - http://xrl.us/bjn8q God gave us two eyes and ten fingers so we will type five times as much as we read. _______________________________________________ Linux-il mailing list [email protected] http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
