From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752296Ab1LLJft (ORCPT ); Mon, 12 Dec 2011 04:35:49 -0500 Received: from mx2.parallels.com ([64.131.90.16]:50563 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751386Ab1LLJfr (ORCPT ); Mon, 12 Dec 2011 04:35:47 -0500 Message-ID: <4EE5CACD.5080606@parallels.com> Date: Mon, 12 Dec 2011 13:35:09 +0400 From: Glauber Costa User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:7.0) Gecko/20110927 Thunderbird/7.0 MIME-Version: 1.0 To: Peter Zijlstra CC: Paul Turner , , linux-kernel , , Linux Containers , KAMEZAWA Hiroyuki , Balbir Singh , Serge Hallyn , Frederic Weisbecker Subject: Re: How to draw values for /proc/stat References: <4EDC8FB1.60407@parallels.com> <1323439411.17673.65.camel@twins> <4EE22179.5090106@parallels.com> <1323682413.16764.55.camel@twins> In-Reply-To: <1323682413.16764.55.camel@twins> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/12/2011 01:33 PM, Peter Zijlstra wrote: > On Fri, 2011-12-09 at 12:55 -0200, Glauber Costa wrote: >> On 12/09/2011 12:03 PM, Peter Zijlstra wrote: > >>> Namespaces seem to be about limiting visibility, cgroups about >>> controlling resources. >>> >>> The two things are hopelessly disjoint atm, but I believe someone was >>> looking at this mess. >> >> I did take a look at this (if anyone else was, I'd like to know so we >> can share some ideas), but I am not convinced we should do anything to >> join them anymore. We virtualization people are to the best of my >> knowledge the only ones doing namespaces. Cgroups, OTOH, got a lot bigger. >> >> What I am mostly concerned about now, is how consistent they will be. >> /proc always being always global indeed does make sense, but my question >> still stands: if you live in a resource-controlled world, why should you >> even see resources you will never own ? > > Since without namespaces you can still see the rest of the world. So it > makes sense to me to still see all resources too. > > Also, proportional controllers might not see a consistent slice of the > resource, making the stats rather awkward to interpret. > > Furthermore, not everybody might care about these statistics at all and > I know pjt objected to being subjected to the extra accounting (pjt do > speak up etc..). > >> If it is not co-mounted, we draw the global value. If you don't mount >> it, I someone does not mount it, I can assure you he doesn't care about >> it. We for sure will. > > Anyway, looking at the rest of the emails in this thread the current > proposal is a cgroup mount option that indicates if you want these > per-cgroup stats or not, right? Well, it is something in this direction. I don't think it's entirely clear what exactly it will look like, but it seems we're making progress.