Hi, On Thu, May 28, 2015 at 06:01:33PM +0000, Noel Grandin wrote: > Wasn't someone going to look at speeding that up? Make check is not > currently making very good use of multiple cores and it has a long tail > where only one or two cores are busy.
I cant fully confirm that -- at least not combined with Michaels 15 minutes number. Good ol' big Bertha with two Opteron 6272s has 32 cores, but mediocre single-threaded performance compared with some of todays offerings. Still[1]: -j real 5m 9.091s user 25m12.250s sys 2m53.420s -j32 real 5m30.133s user 29m46.310s sys 3m10.660s -j8 real 6m35.434s user 19m36.700s sys 2m 6.390s -j1 real 34m11.814s user 17m51.990s sys 1m52.470s (all above along with moderate desktop use alongside: Firefox, mplayer audio streaming etc. -- so not too scientific.) And with this I see a lot of processes running parallel till the end. This suggests to me that the stuff is quite parallelized -- however none of the testing threads seem to be CPU-bound rather the Java-stuff seems to be IO bound (for IPC?) with the slowest test unit taking ~5 minutes. Thus even 32 jobs or more dont seem to keep more than one core busy. At least for people with a meager duo-core laptop or somesuch, this suggests you should try: time make check PARALLELISM=9999 # aka forkbomb me please And if that doesnt explode your RAM, it should help you quite a bit and you should end up with 5 minutes for 'make check' -- quite independant of your hardware, as much of that seems IO-bound idling. If we want to cut down on that 5 minutes, we would need to touch the JunitTest internals. Best, Bjoern [1] As a sidenote: I noted that linking with debug symbols takes at least 4 times as long as without debug symbols. Given that linking happens at the end of the build with a narrow dependency tree left (as libraries are daisy-chained dependency-wise for linking), you are really penalized for building with symbols when you dont need those, as it can easily dry out paralellism. So dont do that: Rather than building with symbols everywhere and then skipping on tests, better build without symbols unless you are debugging, but _run the tests_. [2] On my ancient notebook with a i7-2720QM (a modern 4th gen i7-4770HQ is at least 50% faster at the same speed) I find the following with disabling Junittest_toolkit_unoapi as it was failing on that checkout. time make check PARALLELISM=9999: reall 5m15.351s user 15m52.808s sys 1m10.073s time make check (thus -j8): real 6m2.806s user 14m32.157s sys 1m1.861s time make check PARALLELISM=1: real 41m 7.984s user 27m33.174s sys 1m13.949s _______________________________________________ LibreOffice mailing list LibreOffice@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/libreoffice
