Subject: Re: high power consumption in recent kernels
From: Peter Zijlstra <peterz@infradead.org>
To: Norbert Preining <preining@logic.at>
Cc: Arjan van de Ven <arjan@infradead.org>, linux-kernel@vger.kernel.org,
       Ingo Molnar <mingo@elte.hu>, akpm <akpm@linux-foundation.org>,
       Mike Galbraith <efault@gmx.de>, tglx <tglx@linutronix.de>
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Date: Thu, 08 Jul 2010 21:06:31 +0200
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On Thu, 2010-07-08 at 17:59 +0200, Peter Zijlstra wrote:

> OK, so Arjan said the gain could come from tricking the idle governor
> into not using deeper C states. He also said he significantly cured said
> governor in .35.
> 
> Mike could you re-run your netperf tests that showed the 10% throughput
> gain? Hopefully the fixed governor will yield the same result and we can
> kill off this ratelimit thing.

FWIW, on my test-box, 35-rc4-tip, using ondemand:

with    nohz_ratelimit() : ~2119.54 MB/s
without nohz_ratelimit() : ~2353.03 MB/s

Seems to suggest we should simply kill the thing..
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