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Subject: Re: [RFC PATCH v2 0/2] Saving power by cpu evacuation
 sched_max_capacity_pct=n
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Andi Kleen <andi@firstfloor.org>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>,
       Linux Kernel <linux-kernel@vger.kernel.org>,
       Suresh B Siddha <suresh.b.siddha@intel.com>,
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	 <20090513143550.GU19296@one.firstfloor.org>
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Date: Wed, 13 May 2009 16:36:42 +0200
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On Wed, 2009-05-13 at 16:35 +0200, Andi Kleen wrote:
> On Wed, May 13, 2009 at 06:41:00PM +0530, Vaidyanathan Srinivasan wrote:
> > * Using sched_mc=3,4,5 to evacuate 1,2,4 cores is completely
> >   non-intuitive and broken interface.  Ingo wanted to see if we can
> >   model a global percentile tunable that would map to core throttling.
> 
> I have one request. CPU throttling is already a very well established
> term in the x86 world, refering to thermal throttling when the CPU
> overheats. This is implemented by ACPI and the CPU. It's always
> a very bad thing that should be avoided at all costs.

Its about avoiding that.