From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Serge E. Hallyn" Subject: Re: [RFD][PATCH] memcg: Move Usage at Task Move Date: Thu, 12 Jun 2008 08:17:48 -0500 Message-ID: <20080612131748.GB8453@us.ibm.com> References: <20080606105235.3c94daaf.kamezawa.hiroyu@jp.fujitsu.com> <6599ad830806110017t5ebeda78id1914d179a018422@mail.gmail.com> <20080611164544.94047336.kamezawa.hiroyu@jp.fujitsu.com> <6599ad830806110104n99cdc7h80063e91d16bf0a5@mail.gmail.com> <20080611172714.018aa68c.kamezawa.hiroyu@jp.fujitsu.com> <6599ad830806110148v65df67f8ge0ccdd56c21c89e0@mail.gmail.com> <20080612140806.dc161c77.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20080612140806.dc161c77.kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@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: KAMEZAWA Hiroyuki Cc: "yamamoto-jCdQPDEk3idL9jVzuh4AOg@public.gmane.org" , "nishimura-YQH0OdQVrdy45+QrQBaojngSJqDPrsil@public.gmane.org" , "linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org" , "containers-qjLDD68F18O7TbgM5vRIOg@public.gmane.org" , Paul Menage , "xemul-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org" , "balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org" List-Id: containers.vger.kernel.org Quoting KAMEZAWA Hiroyuki (kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org): > On Wed, 11 Jun 2008 01:48:20 -0700 > "Paul Menage" wrote: > > > On Wed, Jun 11, 2008 at 1:27 AM, KAMEZAWA Hiroyuki > > wrote: > > > Sorry. try another sentense.. > > > > > > I think cgroup itself is designed to be able to be used without middleware. > > > > True, but it shouldn't be hostile to middleware, since I think that > > automated use will be much more common. (And certainly if you count > > the number of servers :-) ) > > > > > IOW, whether using middleware or not is the matter of users not of developpers. > > > There will be a system that system admin controlles all and move tasks by hand. > > > ex)...personal notebooks etc.. > > > > > > > You think so? I think that at the very least users will be using tools > > based around config scripts, rule engines and libcgroup, if not a > > persistent daemon. > > > I believe some users will never use middlewares because of their special > usage of linux. > > > > > >> If the common mode for middleware starting a new cgroup is fork() / > > >> move / exec() then after the fork(), the child will be sharing pages > > >> with the main daemon process. So the move will pull all the daemon's > > >> memory into the new cgroup > > >> > > > My patch (this patch) just moves Private Anon page to new cgroup. (of mapcount=1) > > > > OK, well that makes it more reasonable regarding the above problem. > > But I can still see problems if, say, a single thread moves into a new > > cgroup, you move the entire memory. Perhaps you should only do so if > > the mm->owner changes task? > > > > Thank you for pointing out. I'll add mm->owner check. > > BTW, should we have a cgroup for SYSVIPC resource controller and devide it > from memory resource controller ? I think that per-task on-demand usage > accounting is not suitable for shmem (and hugepage). > per-creater (caller of shmget()) accounting seems to be better for me. > > Just a question: > What happens when a thread (not thread-group-leader) changes its ns by > ns-cgroup ? not-allowed ? I don't quite understand the question. I assume you're asking whether your cgroup, when composed with ns, will refuse a task in cgroup /cg/1/2 from being able to mkdir /cg/1/2/3 echo $$ > /cg/1/2/3/tasks or unshare(CLONE_NEWNS) which the ns cgroup would allow, and what your cgroup would do in that case. If your question ("not-allowed ?") is about ns cgroup behavior then please rephrase. thanks, -serge