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Date: Tue, 15 Apr 2014 15:13:11 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@elte.hu>, "rjw@rjwysocki.net" <rjw@rjwysocki.net>,
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        "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
        Alex Shi <alex.shi@linaro.org>,
        Morten Rasmussen <morten.rasmussen@arm.com>
Subject: Re: [RFC PATCHC 0/3] sched/idle : find the idlest cpu with cpuidle
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On Tue, Apr 01, 2014 at 11:05:16AM +0200, Vincent Guittot wrote:
> >> We are working on a bench which can generate middle load pattern with
> >> idle CPUs but it's not available yet. In the mean time, one bench that
> >> plays with idle time is cyclictest, it will not give you performance
> >> results but only scheduling latency which might be what you are
> >> looking for.
> >
> >
> > Yeah, thanks. I believe I know what is in the rt-tests package :)
> >
> > What I meant is what kind of values would you like to see with this patchset
> > ?
> 
> IIUC, you patch tries to improve the wake up latency of a task by
> selecting the CPUs with the shallowest C-state, so this metrics seems
> to be a good candidate

cyclic-test might be too regular to really measure anything though.