Re: PATCH] cpuidle: A new variant of the menu governor to boost IOperformance

From: Matthew Garrett
Date: Sat Sep 12 2009 - 07:41:57 EST


On Sat, Sep 12, 2009 at 05:26:47AM +0200, Arjan van de Ven wrote:
> On Fri, 11 Sep 2009 23:03:09 +0100
> Matthew Garrett <mjg59@xxxxxxxxxxxxx> wrote:
>
> > When you say that a bit more power was used, is that instantaneous
> > power draw or total power consumption over the run of the benchmark?
> > I'd have expected that completing it 50% faster and then going idle
> > would be a win overall.
>
> I meant power, not total energy :-)
>
> in terms of energy it's a win if you only do a fixed amount of work...

Ok, so not really a downside. Not entirely relatedly, we've also seen io
throughput issues related to P-states - using ondemand, we get reduced
throughput until the number of clients becomes high enough to push the
system into a higher P state. Is this something you've been able to
measure?

--
Matthew Garrett | mjg59@xxxxxxxxxxxxx
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