From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Zefan Subject: Re: [PATCH 6/7] [RFC] Support multiply-bindable cgroup subsystems Date: Wed, 18 Mar 2009 11:09:27 +0800 Message-ID: <49C065E7.8060901@cn.fujitsu.com> References: <20090312104507.24154.71691.stgit@menage.corp.google.com> <20090312105147.24154.62638.stgit@menage.corp.google.com> <49BF4744.5060309@cn.fujitsu.com> <49C057EB.1000307@cn.fujitsu.com> <6599ad830903171916x7364ec7cw76975d71d5125d82@mail.gmail.com> <49C05EDF.5010607@cn.fujitsu.com> <6599ad830903171943x7884cb03w8f22fa1629d667b3@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <6599ad830903171943x7884cb03w8f22fa1629d667b3-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Paul Menage Cc: containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Balbir Singh List-Id: containers.vger.kernel.org CC: Balbir Singh Paul Menage wrote: > On Tue, Mar 17, 2009 at 7:39 PM, Li Zefan wrote: >>> - always display one line for each subsystem; if a subsystem is >>> multiply-bindable then the "hierarchy id" and "num cgroups" columns >>> may be empty or have multiple (comma or slash-separated?) values >>> >> Then "hierarchy id" is no long a single number.. > > Correct. > >>> - for a multiply-bindable subsystem, have a header line to indicate >>> that the subsystem exists, and then a separate line for each bound >>> instance of the subsystem. >>> >> I think it's better to show every subsystems including debug_subsys in >> /proc/cgroups, and show exactly n lines of debug_susys if we have n >> hierarcies with debug_subsys binded, but no header line. > > But that gives a contradiction when n == 0 - we can't show exactly 0 > lines for an unbound multi subsys, and still show every subsystem. > I don't see what's wrong with this behavior: multi subsys sits in rootnode if it's unbound, and is removed from rootnode if it's binded at least in one hierarchy. > Does libcgroup actually parse /proc/cgroup? If not, maybe we should Balbir may answer this. :) > just break the format now and replace it with something more > extensible for future changes. > Even /proc/cgroup is ok, I don't think we can break this based on assumption that on one is making use of /proc/cgroups. :( >> And some cgroup test programs, like controller tests in ltp and some >> test programs that I wrote, but they are ok for this change. > > Right, changes to test programs aren't a compatibility issue. >