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Subject: Re: [PATCH 2/2] cpuhotplug: make get_online_cpus() scalability by
 using percpu counter
From: Peter Zijlstra <peterz@infradead.org>
To: Lai Jiangshan <laijs@cn.fujitsu.com>
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Date: Mon, 12 Apr 2010 14:34:30 +0200
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On Mon, 2010-04-12 at 20:30 +0800, Lai Jiangshan wrote:
> Because read-preference RWL will cause write site starvation.

Sure, but why is that a problem? Hotplug should be a rare event, who
cares if it takes a while to come through.