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Subject: Re: [rfc][patch] improved interactive starvation patch against
	2.6.16
From: Mike Galbraith <efault@gmx.de>
To: Willy Tarreau <willy@w.ods.org>
Cc: lkml <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
       Andrew Morton <akpm@osdl.org>, Peter Williams <pwil3058@bigpond.net.au>,
       Nick Piggin <nickpiggin@yahoo.com.au>, Con Kolivas <kernel@kolivas.org>
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	 <20060330115540.GA4914@w.ods.org>  <1143728558.7840.11.camel@homer>
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Date: Thu, 30 Mar 2006 20:23:24 +0200
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On Thu, 2006-03-30 at 16:22 +0200, Mike Galbraith wrote:
> +		if (expired_starving(rq)) {
> +			int limit = MIN_TIMESLICE + CURRENT_BONUS(p);
> +			int runtime = now - p->timestamp;
> +
> +			runtime = NS_TO_JIFFIES(runtime);
> +			if (runtime >= limit && p->time_slice >= limit) {
> +
> +				dequeue_task(p, rq->active);
> +				enqueue_task(p, rq->expired);
> +				set_tsk_need_resched(p);
> +				if (p->prio < rq->best_expired_prio)
> +					rq->best_expired_prio = p->prio;
> +			}
> +		}

This bit isn't cutting it.  expired_starving() is routine enough that
short slicing (on this scale at least) is noticed.  Don't waste your
time with this one.

	-Mike