From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: How to draw values for /proc/stat Date: Mon, 12 Dec 2011 10:33:33 +0100 Message-ID: <1323682413.16764.55.camel@twins> References: <4EDC8FB1.60407@parallels.com> <1323439411.17673.65.camel@twins> <4EE22179.5090106@parallels.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: <4EE22179.5090106-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Glauber Costa Cc: Paul Turner , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel , devel-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org, Linux Containers , KAMEZAWA Hiroyuki , Balbir Singh , Serge Hallyn , Frederic Weisbecker 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? -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html