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Date: Wed, 5 Sep 2012 13:48:30 +0400
From: Glauber Costa <glommer@parallels.com>
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To: Tejun Heo <tj@kernel.org>
CC: Peter Zijlstra <a.p.zijlstra@chello.nl>, <linux-kernel@vger.kernel.org>,
        <cgroups@vger.kernel.org>, <linux-mm@kvack.org>, <davej@redhat.com>,
        <ben@decadent.org.uk>, <pjt@google.com>, <lennart@poettering.net>,
        <kay.sievers@vrfy.org>
Subject: Re: [RFC 0/5] forced comounts for cgroups.
References: <20120905081439.GC3195@dhcp-172-17-108-109.mtv.corp.google.com> <50470A87.1040701@parallels.com> <20120905082947.GD3195@dhcp-172-17-108-109.mtv.corp.google.com> <50470EBF.9070109@parallels.com> <20120905084740.GE3195@dhcp-172-17-108-109.mtv.corp.google.com> <1346835993.2600.9.camel@twins> <20120905091140.GH3195@dhcp-172-17-108-109.mtv.corp.google.com> <50471782.6060800@parallels.com> <1346837209.2600.14.camel@twins> <50471C0C.7050600@parallels.com> <20120905094520.GM3195@dhcp-172-17-108-109.mtv.corp.google.com>
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On 09/05/2012 01:45 PM, Tejun Heo wrote:
> Hello,
> 
> On Wed, Sep 05, 2012 at 01:31:56PM +0400, Glauber Costa wrote:
>>> > > I simply don't want to have to do two (or more) hierarchy walks for
>>> > > accounting on every schedule event, all that pointer chasing is stupidly
>>> > > expensive.
>> > 
>> > 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.
> Nope, as I wrote in the other reply, 

Would you mind, then, stopping for a moment and telling us what it is,
then, that you envision?