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Subject: Re: sched_fair: the schedule check condition?
From: Mike Galbraith <efault@gmx.de>
To: figo zhang <figo1802@gmail.com>
Cc: linux-kernel@vger.kernel.org
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Date: Fri, 05 Mar 2010 09:33:51 +0100
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On Fri, 2010-03-05 at 15:56 +0800, figo zhang wrote:
> hi,
> 
> in check_preempt_tick() funtion, the check schedule condition the
> reality increasing runtime "delta_exec"
> and vruntime increasing "delta", and reality ideal time "ideal_runtime":
> 
>             if (delta_exec > ideal_runtime)
> and
>             if (delta > ideal_runtime)
> 
> if equal,  it should be need schedule?

Moving the border 1 ns just doesn't matter given the huge pile of ns on
either side of that border.

	-Mike