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Date: Fri, 14 Oct 2011 20:08:09 +0400
From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Frederic Weisbecker <fweisbec@gmail.com>, Tejun Heo <tj@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Kay Sievers <kay.sievers@vrfy.org>, linux-kernel@vger.kernel.org,
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        Oleg Nesterov <oleg@redhat.com>, Paul Menage <paul@paulmenage.org>,
        "Rafael J. Wysocki" <rjw@sisk.pl>,
        Pavel Emelyanov <xemul@parallels.com>
Subject: Re: A =?utf-8?Q?Plumber=E2=80=99?= =?utf-8?Q?s?= Wish List for Linux
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On Fri, Oct 14, 2011 at 08:01:10PM +0400, Cyrill Gorcunov wrote:
...
> > Well, wouldn't it be better to pull that complexity to userspace?
> > After all, moving tasks from a cgroup to another is not a performance
> > critical operation so that probably doesn't need to be all handled by
> > the kernel.
> > 
> > If one worries about concurrent clone/fork while moving tasks, then
> > freezing the cgroup and moving its tasks away from userspace could
> > be enough?
> 
> Well, it's not that problem to make it task-by-task, still I think
> it's just a convenient shortcut :)
> 

Frederic, don't get me wrong, but when I've tried cgroups and freezer for
first time (and I did it not by any script but by hands rather) it makes
me scream out that once I've moved a number of tasks to some freezer cgroup
now I need to move them back again. Of course there is a way to write some
script of whatever but I thought we had some echo -1 shortcut. Anyway,
I can live with it ;)

	Cyrill