On 19/09/16 05:08 AM, Carsten Haitzler (The Rasterman) wrote: > On Mon, 19 Sep 2016 11:07:15 +0200 Stefan Schmidt <ste...@osg.samsung.com> > said: > >> Hello. >> >> On 16/09/16 21:11, Derek Foreman wrote: >>> derekf pushed a commit to branch master. >>> >>> http://git.enlightenment.org/core/efl.git/commit/?id=a17ac66f0a0b089dde0b2e550523b0d59ec97f52 >>> >>> commit a17ac66f0a0b089dde0b2e550523b0d59ec97f52 >>> Author: Derek Foreman <der...@osg.samsung.com> >>> Date: Thu Sep 15 16:05:25 2016 -0500 >>> >>> render_thread: Attempt to set affinity to a random fast core >>> >>> We've been pinning the render thread for every EFL process to core 0. >>> This is a bit silly in the first place, but some big.LITTLE arm systems, >>> such as exynos 5422, have the LITTLE cores first. >>> >>> On those systems we put all the render threads on a slow core. >>> >>> This attempts to fix that by using a random core from the pool of fast >>> cores. >>> >>> If we can't determine which cores are fast (ie: we're not on a >>> linux kernel with cpufreq enabled) then we'll continue doing what we've >>> always done. >> >> I had to revert this patch as it broke all efl builds for me. Locally >> and on Jenkins. Edje_cc segfaulted on the in tree edc files. Error >> message is in the revert commit message. >> >> From the description here this change would still be needed but in a >> non breaking way. :) > > how about simply removing the pinning (affinity) entirely? > I thought about that... The render thread's still going to take a performance hit if it bounces from processor to processor much (it's probably pathologically bad for cache invalidation?)
Also, if it bounces around on the "LITTLE" cores on a big.LITTLE system it'll have really bad performance characteristics... There's a group working on improving the scheduler to better handle non uniform multi-processor systems, so eventually we shouldn't need this anymore, but I think for now it's generally a win. ------------------------------------------------------------------------------ _______________________________________________ enlightenment-devel mailing list enlightenment-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/enlightenment-devel
