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Message-ID: <1322049459.14799.45.camel@twins>
Subject: Re: [patch 6/7] sched: use rq->avg_event to resurrect nohz
 ratelimiting
From: Peter Zijlstra <peterz@infradead.org>
To: Mike Galbraith <mgalbraith@suse.de>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@elte.hu>, Paul Turner <pjt@google.com>
Date: Wed, 23 Nov 2011 12:57:39 +0100
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On Tue, 2011-11-22 at 15:24 +0100, Mike Galbraith wrote:
> Entering nohz at high frequency eats cycles, ratelimit it
> just as we do idle_balance(), and for the same reason.

ideally we should have some per-arch information on how costly it
actually is to enter/leave nohz.

Also, can you confirm, or otherwise run this by whoemever reported that
power-usage regression the last time we tried this?