linux-kernel - Re: [patch 6/7] sched: use rq->avg_event to resurrect nohz ratelimiting

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Message-ID: <1322049459.14799.45.camel@twins>
Date:	Wed, 23 Nov 2011 12:57:39 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Mike Galbraith <mgalbraith@...e.de>
Cc:	Suresh Siddha <suresh.b.siddha@...el.com>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...e.hu>, Paul Turner <pjt@...gle.com>
Subject: Re: [patch 6/7] sched: use rq->avg_event to resurrect nohz
 ratelimiting

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?

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