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Date: Mon, 17 Oct 2011 16:19:20 +0100
From: Matthew Garrett <mjg@redhat.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
        Arjan van de Ven <arjan@linux.intel.com>,
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Subject: Re: [PATCH, v10 3/3] cgroups: introduce timer slack controller
Message-ID: <20111017151920.GA16664@srcf.ucam.org>
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On Mon, Oct 17, 2011 at 05:11:00PM +0200, Peter Zijlstra wrote:
> On Mon, 2011-10-17 at 15:59 +0100, Matthew Garrett wrote:
> > I'm not saying that it's a problem. I'm saying that your approach 
> > changes behavioural semantics in a way that may violate application 
> > expectations just as surely as changing the timer behaviour does. 
> > There's no free approach.
> 
> I'm not saying its free, I'm saying its a much better approach since it
> gets rid of the entire problem instead of papering over the worst of it.

It solves it for a specific case, ie animations. Any other timer driven 
behaviour continues. It really does need to be tied to session idle, not 
application visibility, and enforcement at the X level does nothing to 
help that.

-- 
Matthew Garrett | mjg59@srcf.ucam.org