Re: [PATCH] cpuidle: menu: use nr_running instead of cpuload forcalculating perf mult

From: Peter Zijlstra
Date: Mon Jun 04 2012 - 17:14:48 EST


On Mon, 2012-06-04 at 13:45 -0700, Arjan van de Ven wrote:
> On 6/4/2012 1:31 PM, Peter Zijlstra wrote:
> >
> > And like I said many times now, if you inflate some of the idle periods,
> > the work shifts (it doesn't become less) and a next idle period will be
> > smaller -- since we'll only become idle again once all work is done.
>
> this is what is not really correct.
>
> you can be idle for many reasons, not just because you have no work
> left. most common is waiting for a disk IO. the idle period for that
> will not get shorter just because the previous one took more time.

Then you're back to synchronous behaviour and your earlier claim that it
is was not about latency response is false.
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