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Date: Wed, 26 Aug 2009 16:40:09 -0400 (EDT)
From: Christoph Lameter <cl@linux-foundation.org>
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To: Ingo Molnar <mingo@elte.hu>
cc: Peter Zijlstra <peterz@infradead.org>, raz ben yehuda <raziebe@gmail.com>,
       Maxim Levitsky <maximlevitsky@gmail.com>,
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       wiseman@macs.biu.ac.il, lkml <linux-kernel@vger.kernel.org>,
       linux-rt-users@vger.kernel.org
Subject: Re: RFC: THE OFFLINE SCHEDULER
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On Wed, 26 Aug 2009, Ingo Molnar wrote:

> ( If you on the other hand were approaching this issue with
>   pragmatism and with intellectual honesty, if you were at the end
>   of a string of patches that gradually improved latencies but
>   couldnt get them below a certain threshold, and if scheduler
>   developers couldnt give you any ideas what else to improve, and
>   _then_ suggested some other solution, you might have a point.
>   You are far away from being able to claim that. )

Intellectual honesty? Wish I would be seeing it. So far there is not even
the uptake required on your side to discuss the problem.

There is no threshold. HPC and other industries want processors as
a whole with all their abilities. They will squeeze the last bit of
performance out of them.

> to have sharp teeth nor any apparent poison fangs) - i simply concur
> with the reasons Peter listed that it is a technically inferior
> solution.

Ok so you are saying that the reduction of OS latencies will make the
processor completely available and have no disturbances like OFFLINE scheduling?

Peter has not given a solution to the problem. Nor have you.