From: Con Kolivas <kernel@kolivas.org>
To: Ingo Molnar <mingo@elte.hu>
Subject: Re: interactive task starvation
Date: Wed, 22 Mar 2006 01:28:06 +1100
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On Wednesday 22 March 2006 01:25, Ingo Molnar wrote:
> * Con Kolivas <kernel@kolivas.org> wrote:
> > What you're fixing with unfairness is worth pursuing. The 'ls' issue
> > just blows my mind though for reasons I've just said. Where are the
> > magic cycles going when nothing else is running that make it take ten
> > times longer?
>
> i believe such artifacts are due to array switches not happening (due to
> the workload getting queued back to rq->active, not rq->expired), and
> 'ls' only gets a timeslice once in a while, every STARVATION_LIMIT
> times. I.e. such workloads penalize the CPU-bound 'ls' process quite
> heavily.

With nothing else running on the machine it should still get all the cpu no 
matter which array it's on though.

Con
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