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Message-ID: <1342808550.2583.48.camel@twins>
Subject: Re: [PATCHSET] workqueue: reimplement CPU hotplug to keep idle
 workers
From: Peter Zijlstra <peterz@infradead.org>
To: Tejun Heo <tj@kernel.org>
Cc: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org,
        tglx@linutronix.de, linux-pm@vger.kernel.org
Date: Fri, 20 Jul 2012 20:22:30 +0200
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On Fri, 2012-07-20 at 10:50 -0700, Tejun Heo wrote:
> Also, re-binding busy workers is easy.  The idle ones are difficult
> and we have to do that anyway for PM optimization.  What would be the
> benefit of not re-binding busy ones at the risk of continually
> transferring workers to another CPU given the right workload + CPU
> down/up patterns? 

I really think people who use hotplug at high frequencies are on drugs
and doing it wrong.