On Mon, 16 Mar 2015 16:05:37 +0100 Heinz Diehl <htd+ml@xxxxxxxxxx> wrote: > On 09.03.2015, Martin Cigorraga wrote: > > > Just a minor clarification: when compiling, the -j flag should > > point to a unit above your available cores in order to fully > > utilize all of them. > > Curious what would happen, I remembered this mail when compiling a > new kernel today. A "nice -n 19 make -j" opened *hundreds* of cc > incarnations, pushed the load to over 800 and seriously blocked the > machine (an 8-core Xeon with 16 GB of RAM) within *seconds*! Lucky you! Are you using F21? Which kernel? So, are you using rpmbuild with the src.rpm package, or compiling directly from the source tree? What happens if you use -j 4? I would think you should get somewhere between 3 and 4 cores. The recommendation I saw to fully use all cores, were from cores+1 to cores*3. Cores*1.5 was a popular one, to allow for io slowness. When I tried -j, I saw all the jobs queue, but only one core was used. Thanks for reporting back. -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines Have a question? Ask away: http://ask.fedoraproject.org
