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Date: Wed, 26 Aug 2009 15:15:26 -0600
From: "Chris Friesen" <cfriesen@nortel.com>
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To: Andrew Morton <akpm@linux-foundation.org>
CC: Christoph Lameter <cl@linux-foundation.org>, mingo@elte.hu,
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Subject: Re: RFC: THE OFFLINE SCHEDULER
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On 08/26/2009 02:50 PM, Andrew Morton wrote:

> What problem?
> 
> All I've seen is "I want 100% access to a CPU".  That's not a problem
> statement - it's an implementation.
> 
> What is the problem statement?

I can only speak for myself...

In our case the problem statement was that we had an inherently
single-threaded emulator app that we wanted to push as hard as
absolutely possible.

We gave it as close to a whole cpu as we could using cpu and irq
affinity and we used message queues in shared memory to allow another
cpu to handle I/O.  In our case we still had kernel threads running on
the app cpu, but if we'd had a straightforward way to avoid them we
would have used it.

Chris