On Thu, 2010-12-02 at 03:03 +0100, Dennis Jacobfeuerborn wrote: > I just noticed that when I boot with "nohz=off" I get improved vmstat > numbers. When playing a YouTube video I get an idle percentage of around > 25-30 but when I boot with "nohz=off" the system seems to cope much better > and show an idle percentage of 50. Can anyone shed some light on what is > going on here? > Given this and the problems described in bug 650934 I'm wondering how > trustworthy Fedoras system metrics are. Values for load and cpu usage > shouldn't really be this flaky. There's at least one bug in recent kernels where active CPU time (as reported by top and friends) are wildly overaccounted. powertop still seems to show a pretty reasonable estimate though. Also, you didn't mention which hardware this was with, but at least on Intel GPU systems there's a known issue where graphics performance suffers when the CPU appears idle but the GPU has work to do; the system enters a lower C state based on the CPU workload, but that lowers the memory clock, which means the GPU gets starved for bandwidth. - ajax -- test mailing list test@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe: https://admin.fedoraproject.org/mailman/listinfo/test
