From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Zefan Subject: Re: [RFD] cgroup: about multiple hierarchies Date: Thu, 23 Feb 2012 15:59:44 +0800 Message-ID: <4F45F1F0.2010102@cn.fujitsu.com> References: <20120221211938.GE12236@google.com> <20120222163858.GB4128@redhat.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120222163858.GB4128-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Vivek Goyal Cc: Tejun Heo , containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Andrew Morton , Kay Sievers , Lennart Poettering , Frederic Weisbecker , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Christoph Hellwig > Trying to make all the controllers uniform in terms of their treatment > of cgroup hiearchy sounds like a good thing to do. Agreed. Apart from nesting cgroups, there're other inconsistencies. - Some controllers disallow more than one cgroup layer. That's the new net_prio controller, and I don't know why it's made so, but I guess it's fine to eliminate this restriction. - Some controllers move resource charges when a task is moved to a different cgroup, but some don't? - Some controllers disallow task attaching under some circumstances. So if we have a single hierarchy with all subsystems, the chance that attaching a task to a cgroup fails may be bigger. > Once that is done, > one can probably see if it is worth to put all the controllers in a > single hierarchy. >