From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Zefan Subject: Re: Can not remove the subdirectory in cgroup pseudo-filesystem Date: Thu, 26 Mar 2009 09:15:00 +0800 Message-ID: <49CAD714.4080307@cn.fujitsu.com> References: <20090325163702.GA17626@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: 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: anqin Cc: Linux Containers List-Id: containers.vger.kernel.org anqin wrote: >> Yes you have to initialize some cpuset files first. Otherwise >> the tasks have no access to any memory or cpus. >> > > Oh... thank you for reminding. Previously, I run my tests in > a experimental kernel, it seems someone has set the > parameters. > > > BTW, is it possible currently to combine two tasks into > one cgroup? for instance, I have run two bashes (bash_A and I recomend you to read Documentation/cgroups/cgroups.txt to know cgroup better. Cgroup is used to aggregate/partition sets of tasks, so of course you can put more than 1 task into a cgroup. > bash_B). Now, in bash_A, I created a cgroup in procfs: > > # mount -t cgroup cgroup /mnt/cgrp mount cgroupfs with all cgroup subsystems is not so sane IMO. > # cd /mnt/cgrp > # mkdir test > # echo $$ > test/tasks > > Then, I would like to add bash_B in this task group but > fail: > > # echo #(PID_OF_bash_B) > test/tasks > -bash: echo: write error: Operation not permitted > That's because ns_cgroup is binded in this cgroup hierarchy, and it's ns_cgroup that prevents the task attaching, but a patch in -mm tree relaxes this check, and you won't see this restriction when using ns_cgroup. > It seems the cgroup can not couple two irrelevant > task together, right? > > > Best, > > Anqin