Messages in this thread | | | Date | Fri, 17 Aug 2012 19:47:05 +0100 | From | Matthew Garrett <> | Subject | Re: [discussion]sched: a rough proposal to enable power saving in scheduler |
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On Fri, Aug 17, 2012 at 11:44:03AM -0700, Arjan van de Ven wrote: > On 8/17/2012 11:41 AM, Matthew Garrett wrote: > > On Thu, Aug 16, 2012 at 07:01:25AM -0700, Arjan van de Ven wrote: > >> this is ... a dubiously general statement. > >> > >> for good power, at least on Intel cpus, you want to spread. Parallelism is efficient. > > > > Is this really true? In a two-socket system I'd have thought the benefit > > of keeping socket 1 in package C3 outweighed the cost of keeping socket > > 0 awake for slightly longer. > > not on Intel > > you can't enter package c3 either until every one is down. > (e.g. memory controller must stay on etc etc)
I thought that was only PC6 - is there any reason why the package cache can't be entirely powered down?
-- Matthew Garrett | mjg59@srcf.ucam.org
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