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Subject: Re: [RFC] CPU controllers?
From: Mike Galbraith <efault@gmx.de>
To: Andrew Morton <akpm@osdl.org>
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Date: Sun, 18 Jun 2006 09:36:16 +0200
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On Sat, 2006-06-17 at 23:42 -0700, Andrew Morton wrote:
> On Sun, 18 Jun 2006 16:11:18 +1000
> Nick Piggin <nickpiggin@yahoo.com.au> wrote:

> > Again, I don't care about the solutions at this stage. I want to know
> > what the problem is. Please?
> 
> Isolation.  To prevent one group of processes from damaging the performance
> of other groups, by providing manageability of the resource consumption of
> each group.  There are plenty of applications of this, not just
> server-consolidation-via-server-virtualisation.

Scheduling contexts do sound useful.  They're easily defeated though, as
evolution mail demonstrates to me every time it's GUI hangs and I see
that a nice 19 find is running, eating very little CPU, but effectively
DoSing evolution nonetheless (journal).  I wonder how often people who
tried to distribute CPU would likewise be stymied by other resources.

	-Mike