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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 19:37:29 +0200
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On Thu, 2009-05-07 at 13:18 -0400, Christoph Lameter wrote:
> On Thu, 7 May 2009, Peter Zijlstra wrote:
> 
> > Therefore, decreasing the HZ value to say 50, we'd get a minimum
> > involuntary preemption granularity of 20ms, something on the high end of
> > barely usable.
> 
> But the schedule is activated when a process is being woken up. The main
> use is for load balancing.

Somehow people like involuntary preemption to happen at slightly more
than glacial pace as well.