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Subject: Re: RFC: THE OFFLINE SCHEDULER
From: Mike Galbraith <efault@gmx.de>
To: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <peterz@infradead.org>,
       raz ben yehuda <raziebe@gmail.com>,
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Date: Thu, 27 Aug 2009 09:15:56 +0200
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On Wed, 2009-08-26 at 15:15 -0400, Christoph Lameter wrote:

> The point of the OFFLINE scheduler is to completely eliminate the
> OS disturbances by getting rid of *all* OS processing on some cpus.

No, that's not the point of OFFSCHED.  It's about offloading kernel
functionality to a peer, and as it currently exists after some years of
development. kernel functionality only.  Raz has already stated that
hard RT is not the point.

<quote> (for full context, jump back a bit in this thread)
> On the other hand, I could see this as a jump platform for more
> proprietary code, something like that: we use linux in out server
> platform, but out "insert buzzword here" network stack pro+ can handle
> 100% more load that linux does, and it runs on a dedicated core....
> 
> In the other words, we might see 'firmwares' that take an entire cpu
for
> their usage.
This is exactly what offsched (sos) is. you got it. SOS was partly
inspired by the notion of a GPU. 
Processors are to become more and more redundant and Linux as an
evolutionary system must use it. why not offload raid5 write engine ?
why not encrypt in a different processor ?
Also , having so many processors in a single OS means a bug prone
system , with endless contention points when two or more OS processors
interacts. let's make things simpler.
</quote>

	-Mike