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Date: Mon, 14 Jan 2002 13:19:25 +1100
From: Rusty Russell <rusty@rustcorp.com.au>
To: Manfred Spraul <manfred@colorfullife.com>
Cc: mingo@elte.hu, linux-kernel@vger.kernel.org
Subject: Re: cross-cpu balancing with the new scheduler
Message-Id: <20020114131925.4fcbd127.rusty@rustcorp.com.au>
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On Sun, 13 Jan 2002 18:01:40 +0100
Manfred Spraul <manfred@colorfullife.com> wrote:

> Is it possible that the inter-cpu balancing is broken in 2.5.2-pre11?
> 
> eatcpu is a simple cpu hog ("for(;;);"). Dual CPU i386.
> 
> $nice -19 ./eatcpu&;
>  <wait>
> $nice -19 ./eatcpu&;
>  <wait>
> $./eatcpu&.
> 
> IMHO it should be
> * both niced process run on one cpu.
> * the non-niced process runs with a 100% timeslice.
> 
> But it's the other way around:
> One niced process runs with 100%. The non-niced process with 50%, and
> the second niced process with 50%.

This could be fixed by making "nr_running" closer to a "priority sum".

Ingo?

Rusty.
-- 
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.
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