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

From: Mike Galbraith
Date: Thu Oct 08 2009 - 10:16:48 EST


On Thu, 2009-10-08 at 06:45 -0700, Arjan van de Ven wrote:
> On Thu, 08 Oct 2009 13:24:22 +0200
> Mike Galbraith <efault@xxxxxx> wrote:
> > Latencytop was accounting uninterruptible and interruptible sleep
> > time up to 5ms, which is not the latency the user is looking for.
>
> it is for everything but the scheduler latency!
>
> latencytop wants to show where you're waiting for disk, etc etc.
> that's not "time on runqueue".
>
> for the scheduler delays a whole different codepath is used!

That explains.. a few things.

-Mike

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