Re: [.32-rc3] scheduler: iwlagn consistently high in "waiting forCPU"

From: Mike Galbraith
Date: Fri Oct 09 2009 - 16:08:05 EST


On Fri, 2009-10-09 at 18:27 +0200, Frans Pop wrote:
> On Friday 09 October 2009, Mike Galbraith wrote:
> > sched: update the clock of runqueue select_task_rq() selected.
> >
> > In try_to_wake_up(), we update the runqueue clock, but select_task_rq()
> > may select a different runqueue than the one we updated, leaving the new
> > runqueue's clock stale for a bit.
> >
> > This patch cures occasional huge latencies reported by latencytop when
> > coming out of idle on a mostly idle NO_HZ box.
>
> This patch (without Arjan's previous one applied) also fixes my latency
> issues. Nice work!

Thanks for the confirmation (and kind words).

-Mike

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