From: Glauber Costa <glommer@parallels.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Tejun Heo <tj@kernel.org>, <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.
Date: Wed, 5 Sep 2012 13:31:56 +0400 [thread overview]
Message-ID: <50471C0C.7050600@parallels.com> (raw)
In-Reply-To: <1346837209.2600.14.camel@twins>
On 09/05/2012 01:26 PM, Peter Zijlstra wrote:
> On Wed, 2012-09-05 at 13:12 +0400, Glauber Costa wrote:
>> On 09/05/2012 01:11 PM, Tejun Heo wrote:
>>> Hello, Peter.
>>>
>>> On Wed, Sep 05, 2012 at 11:06:33AM +0200, Peter Zijlstra wrote:
>>>> *confused* I always thought that was exactly what you meant with unified
>>>> hierarchy.
>>>
>>> No, I never counted out differing granularity.
>>>
>>
>> Can you elaborate on which interface do you envision to make it work?
>> They will clearly be mounted in the same hierarchy, or as said
>> alternatively, comounted.
>>
>> If you can turn them on/off on a per-subtree basis, which interface
>> exactly do you propose for that?
>
> I wouldn't, screw that. That would result in the exact same problem
> we're trying to fix. I want a single hierarchy walk, that's expensive
> enough.
>
>> Would a pair of cgroup core files like available_controllers and
>> current_controllers are a lot of drivers do, suffice?
>
> No.. its not a 'feature' I care to support for 'my' controllers.
>
> 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.
next prev parent reply other threads:[~2012-09-05 9:35 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-04 14:18 [RFC 0/5] forced comounts for cgroups Glauber Costa
2012-09-04 14:18 ` [RFC 1/5] cgroup: allow some comounts to be forced Glauber Costa
2012-09-04 14:18 ` [RFC 2/5] sched: adjust exec_clock to use it as cpu usage metric Glauber Costa
2012-09-04 14:18 ` [RFC 3/5] sched: do not call cpuacct_charge when cpu and cpuacct are comounted Glauber Costa
2012-09-04 14:18 ` [RFC 4/5] cpuacct: do not gather cpuacct statistics when not mounted Glauber Costa
2012-09-04 14:18 ` [RFC 5/5] sched: add cpusets to comounts list Glauber Costa
2012-09-04 21:46 ` [RFC 0/5] forced comounts for cgroups Tejun Heo
2012-09-05 8:03 ` Glauber Costa
2012-09-05 8:14 ` Tejun Heo
2012-09-05 8:17 ` Glauber Costa
2012-09-05 8:29 ` Tejun Heo
2012-09-05 8:35 ` Glauber Costa
2012-09-05 8:47 ` Tejun Heo
2012-09-05 8:55 ` Glauber Costa
2012-09-05 9:07 ` Tejun Heo
2012-09-05 9:06 ` Glauber Costa
2012-09-05 9:14 ` Tejun Heo
2012-09-05 9:06 ` Peter Zijlstra
2012-09-05 9:07 ` Peter Zijlstra
2012-09-05 9:22 ` Tejun Heo
2012-09-05 9:11 ` Tejun Heo
2012-09-05 9:12 ` Glauber Costa
2012-09-05 9:19 ` Tejun Heo
2012-09-05 9:30 ` Glauber Costa
2012-09-05 9:26 ` Peter Zijlstra
2012-09-05 9:31 ` Glauber Costa [this message]
2012-09-05 9:45 ` Tejun Heo
2012-09-05 9:48 ` Glauber Costa
2012-09-05 9:56 ` Tejun Heo
2012-09-05 10:20 ` Peter Zijlstra
2012-09-06 20:38 ` Tejun Heo
2012-09-06 22:39 ` Glauber Costa
2012-09-06 22:45 ` Tejun Heo
2012-09-05 9:32 ` Tejun Heo
2012-09-05 10:04 ` Peter Zijlstra
2012-09-06 20:46 ` Tejun Heo
2012-09-06 21:11 ` Paul Turner
2012-09-06 22:36 ` Glauber Costa
2012-09-08 13:36 ` Dhaval Giani
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=50471C0C.7050600@parallels.com \
--to=glommer@parallels.com \
--cc=a.p.zijlstra@chello.nl \
--cc=ben@decadent.org.uk \
--cc=cgroups@vger.kernel.org \
--cc=davej@redhat.com \
--cc=kay.sievers@vrfy.org \
--cc=lennart@poettering.net \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=pjt@google.com \
--cc=tj@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).