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Date: Tue, 17 May 2011 21:21:14 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Hillf Danton <dhillf@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>, LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <peterz@infradead.org>,
        Yong Zhang <yong.zhang0@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH] sched: avoid overpull when pulling RT task
Message-ID: <20110518012114.GB23940@home.goodmis.org>
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On Tue, May 17, 2011 at 10:25:54PM +0800, Hillf Danton wrote:
> 
> Efforts are put on the puller's side, but bad result is reached:(
> 
> Another patch is prepared, in which pusher is asked to do the hard works,
> say pushees and tasks are selected.
> 
> Unlike puller who only concerns one runqueue that accepts the pulled tasks,
> pusher delivers tasks to more runqueues, so the overpull could get bigger.
> 
> Please review again, thanks.
> 

Have you actually observed an overpull? And if so, how bad was it?

I hate to be fixing bugs that don't really exist.

-- Steve