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Date: Wed, 26 Aug 2009 19:16:12 +0300
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Subject: Re: RFC: THE OFFLINE SCHEDULER
From: Pekka Enberg <penberg@cs.helsinki.fi>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Lameter <cl@linux-foundation.org>,
       raz ben yehuda <raziebe@gmail.com>,
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Hi Peter,

On Wed, Aug 26, 2009 at 7:03 PM, Peter Zijlstra<peterz@infradead.org> wrote:
> There needs to be some communication between the isolated and non
> isolated part, otherwise what's the point. Even when you'd let it handle
> say a network device as pure firewall, you'd need to configure the
> thing, requiring interaction.

The use case Christoph described was an user-space number cruncher app
that does some network I/O over RDMA IIRC. AFAICT, if he could isolate
a physical CPU for the thing, there would be little or no
communication with the non-isolated part. Yes, the setup sounds weird
but it's a real workload although pretty damn specialized.

On Wed, Aug 26, 2009 at 7:03 PM, Peter Zijlstra<peterz@infradead.org> wrote:
>> > If you think the kernel is too fat and does superfluous things for your
>> > needs, help trim it.
>>
>> Mind boogling nonsense. Please stop fantasizing and trolling.
>
> Oh, to lay down the crack-pipe and sod off.

I guess I'll go for the magic mushrooms then.

                        Pekka