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Subject: Re: [RFC PATCH] sched: START_NICE feature (temporarily niced
 forks) (v4)
From: Mike Galbraith <efault@gmx.de>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@elte.hu>,
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        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Thomas Gleixner <tglx@linutronix.de>, Tony Lindgren <tony@atomide.com>
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Date: Wed, 22 Sep 2010 13:51:04 +0200
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On Tue, 2010-09-21 at 16:04 +0200, Mike Galbraith wrote:

> Perhaps take that vslice penalty, apply it to parent and child, and if
> present, deduct sleep time from their debt, and only credit sleep time
> if there's anything left over?  In any case, seems to me that sleep time
> has to be included in the equation while the penalty is in effect.
> 
> Guess I'll try that, see what happens.

Nothing good.  Several flavors thereof.

> (but that will likely negate much of the benefit for your testcase,
> where parent and child sleep)

(yup, it did)

BTTODB.

	-Mike