I'm getting strange results (and counter-intuitive ones) when trying to compile a program using gcc-4.4.0-3mnb2 on Mandriva Linux Cooker.
The program in question is: https://svn.berlios.de/svnroot/repos/fc-solve/trunk/fc-solve/source (you can checkout it using "svn co"). And I'm getting the following benchmark timings: (in seconds) {{{{{{ dump:126.027262926102 dump-2:124.866523981094 dump-3:125.149952888489 dump-4:125.010930776596 dump-aft-reboot:127.221956968307 dump-flip:123.10272693634 dump-flip-2:121.934360027313 dump-flip-3:121.98522400856 dump-old:130.334769010544 dump-old-aft-reboot:122.411857128143 }}}}}} dump-old is of an old revision before I rebooted. dump-old-aft-reboot is the same version after I reboot the computer. The dump-flip's are after doing "./Tatzer -l p4b" and then "make" (and "make install") and then running: ./freecell-solver-range-parallel-solve 1 32000 500 -l gi The dump-[234] are after doing "./Tatzer -l p4b --without-flip". What this flag does is define the FCS_WITHOUT_CARD_FLIPPING macro, which in turn toggles some #ifndef's in the code that eliminate a lot of code. I verified that with "--without-flip" binaries are smaller. My question is: why is the --without-flip binaries slower than the ones with the flipping logic? So far my best bet is that with the flipping logic enabled (but underused) the code aligns to have fewer cache misses and that it is just a co-incidence that this is the case. I'll appreciate any insights. Regards, Shlomi Fish -- ----------------------------------------------------------------- Shlomi Fish http://www.shlomifish.org/ The Case for File Swapping - http://xrl.us/bjn7i God gave us two eyes and ten fingers so we will type five times as much as we read. _______________________________________________ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il