On Wed, 2016-04-13 at 10:36 -0400, Chris Mason wrote: > On Wed, Apr 13, 2016 at 04:22:58PM +0200, Mike Galbraith wrote:
> > What exactly do you mean by failed affine wakeups? Failed because > > wake_wide() said we don't want one, or because wake_affine() said we > > can't have one? If the later, my thought bubble may have just burst, > > but it still "feels" right. > > I mean this number: > > schedstat_inc(p, se.statistics.nr_wakeups_affine_attempts); > > Is much much much higher than this number: > > schedstat_inc(p, se.statistics.nr_wakeups_affine); > > So, wake_affine said we can't have one. I made a script to sum it up > across all the threads of the webserver workload. Hm, ok, that doesn't really tell us more than there's more to the load than the 1:N bits that wake_wide() apparently did identify fairly well last go, so targeting them still might help. -Mike