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Subject: Re: [RFC 0/5] forced comounts for cgroups.
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Glauber Costa <glommer@parallels.com>
Cc: Tejun Heo <tj@kernel.org>, linux-kernel@vger.kernel.org,
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Date: Wed, 05 Sep 2012 12:20:53 +0200
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On Wed, 2012-09-05 at 13:31 +0400, Glauber Costa wrote:
> 
> You wouldn't have to do more than one hierarchy walks for that. What
> Tejun seems to want, is the ability to not have a particular controller
> at some point in the tree. But if they exist, they are always together. 

Right, but the accounting is very much tied to the control structures, I
suppose we could change that, but my jet-leg addled brain isn't seeing
anything particularly nice atm.

But I don't really see the point though, this kind of interface would
only ever work for the non-controlling and controlling controller
combination (confused yet ;-), and I don't think we have many of those.

I would really rather see a simplification of the entire cgroup
interface space as opposed to making it more complex. And adding this
subtree 'feature' only makes it more complex.