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Subject: Re: [PATCH] x86: Reduce the default HZ value
From: Peter Zijlstra <peterz@infradead.org>
To: Christoph Lameter <cl@linux.com>
Cc: Alok Kataria <akataria@vmware.com>, "H. Peter Anvin" <hpa@zytor.com>,
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Date: Thu, 07 May 2009 19:55:25 +0200
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On Thu, 2009-05-07 at 13:34 -0400, Christoph Lameter wrote:
> On Thu, 7 May 2009, Peter Zijlstra wrote:
> 
> > Somehow people like involuntary preemption to happen at slightly more
> > than glacial pace as well.
> 
> These intervals could be dynamically established by the scheduler.
> 
> If there is a single process running on a processor and no other process
> is contending then there is no need to do involuntary preemption.

Sure, and CONFIG_SCHED_HRTICK does that, the trick is getting it to not
hurt others.