On 22 August 2011 13:22, Michael Meeks <[email protected]> wrote: > Hi Matus, > > On Sat, 2011-08-20 at 23:04 +0200, Matúš Kukan wrote: >> I created patch, which allows link-time optimization (--enable-lto) >> for shared libraries, you need at least gcc-4.5 (I'm not checking for >> version in configure). > > Patch looks great to me :-) > >> I don't know what should I try to test >> if it is really faster and how much. > > Heh ;-) so a 'callgrind' run on startup would be one approach: > > export OOO_EXIT_POST_STARTUP=1 > export OOO_DISABLE_RECOVERY=1 > valgrind --tool=callgrind --simulate-cache=yes --dump-instr=yes ./soffice.bin > -writer --splash-pipe=0 > Unfortunately, I can't try this anymore, I lost my build by mistake.
> And then look at the total number of simulated cycles I guess. On the > other hand it would be perhaps easier, and more interesting to see if > the code is actually smaller ;-) what is the size before and after of > the writer library eg. ? > Heh :), actually the opposite. I remember it was 15MB after lto, normally it's 10 MB. Maybe It's complete wrong with gcc-4.5 or it is doing aggressive inlining or I don't know what. >> Most of the time is running lto1 executable and it eat cca >> 2GB RAM when optimizing sw library. (cca 4,5 minutes for me) > > :-) Of course, if we can get some real wins with it (particularly > putting more code into one big library), then a bit more link time is a > price well worth paying I think. > > I suspect most of the bigger wins come from getting as much as possible > of the code integrated together into one big, mozilla-style library > but ... :-) lets see. > Unfortunately this is not now possible or not easily. We need bigger tail_build. I will write another mail about this. Patch for lto is pushed. Matúš _______________________________________________ LibreOffice mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/libreoffice
