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Subject: Re: RFC: THE OFFLINE SCHEDULER
From: raz ben yehuda <raziebe@gmail.com>
To: Chris Friesen <cfriesen@nortel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
       Christoph Lameter <cl@linux-foundation.org>, mingo@elte.hu,
       peterz@infradead.org, maximlevitsky@gmail.com, efault@gmx.de,
       riel@redhat.com, wiseman@macs.biu.ac.il, linux-kernel@vger.kernel.org,
       linux-rt-users@vger.kernel.org
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Date: Thu, 27 Aug 2009 00:37:43 +0300
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On Wed, 2009-08-26 at 15:15 -0600, Chris Friesen wrote:
> 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
Chris. I offer myself to help anyone wishes to apply OFFSCHED.