On Wed, 2014-01-29 at 13:09 +0100, Ulf Samuelsson wrote: > We discussed this 2.3 months ago. > Did some studies on my dual hex-core machine (24 H/W treads) while > building a cloud9-gnome-image derivative. > This did about 7500 tasks. > > Enabled the CPU supervisors in the panel. > > Everything seems to be ok with BB_NUMBER_THREADS = "24" for about 4-4500 > tasks. > > Then the CPUs are mostly inactive and only 1-2 running for ~500 tasks. > Then parallellism is resumed until about task 7000, and again > only a few CPUs are active.
This is likely whilst the lib and toolchain is getting built. > I believe that some tools use "make" within the Makefile, > and they are written badly, and do not use "-j <n>" for > that part of the build. Which recipes were building at this point? It would be interesting to track them down. > Got my build down to 83 minutes. > > Since I have 96 GB of RAM, I tried creating an 80 GB tmpfs for the build, > and copied the download and the recipes to the ram. > > That shaved only 2 monutes from the build, and some stuff, > still built using only a single CPU. There are certainly dependency bottlenecks in the build such as the toolchain, compiler, gettext, gtk+ and so where large numbers of things need those dependencies to get built before they can proceed. Not sure what we can do to help this though. Cheers, Richard _______________________________________________ Openembedded-core mailing list Openembedded-core@lists.openembedded.org http://lists.openembedded.org/mailman/listinfo/openembedded-core
