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Date: Wed, 5 Dec 2007 22:21:55 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Holger.Wolf@de.ibm.com, schwidefsky@de.ibm.com,
       linux-kernel@vger.kernel.org
Subject: Re: Scheduler behaviour
Message-ID: <20071205212155.GA4764@elte.hu>
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* Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:

> > We discovered performance degradation with dbench when using kernel 
> > 2.6.23 compared to kernel 2.6.22.
> 
> We've fixed a lot of regressions and made a lot of other changes to 
> the scheduler since .23. Could you please try the backport of the 
> latest scheduler on top of .23 to see if any of our recent work solved 
> your problem? (using a backport against .23 or even .22 allows you to 
> test just the scheduler changes in isolation)

actually, i'd suggest to use the CFS backport against .22 right away:

> http://people.redhat.com/mingo/cfs-scheduler/sched-cfs-v2.6.22.13-v24.patch

that would exclude all other changes that happened in 2.6.23.

	Ingo