From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [RFD] cgroup: about multiple hierarchies Date: Tue, 28 Feb 2012 23:00:21 +0100 Message-ID: <1330466421.11248.107.camel@twins> References: <20120221211938.GE12236@google.com> <20120222163858.GB4128@redhat.com> <20120222165714.GC4128@redhat.com> <1329990094.24994.64.camel@twins> <20120223213847.GK19691@redhat.com> <20120223223457.GJ22536@google.com> <20120228211627.GH9920@redhat.com> <1330464100.11248.94.camel@twins> <20120228213526.GI9920@redhat.com> <1330465434.11248.98.camel@twins> <20120228215439.GJ9920@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120228215439.GJ9920-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> List-Id: 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: Vivek Goyal Cc: Frederic Weisbecker , containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Kay Sievers , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Christoph Hellwig , Lennart Poettering , Tejun Heo , cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Andrew Morton On Tue, 2012-02-28 at 16:54 -0500, Vivek Goyal wrote: > On Tue, Feb 28, 2012 at 10:43:54PM +0100, Peter Zijlstra wrote: > > On Tue, 2012-02-28 at 16:35 -0500, Vivek Goyal wrote: > > > For > > > cpu controller, it is priority at the group level no fixed minimum/maximum > > > % shares. And that's a limitation of treating task and group at same level. > > > > Depends on what you mean by min/max %, you can do it on the group level > > by using bandwidth caps (for max) or inverted (max on everybody else, > > for min). > > I was referring to using pure proportional controller. max bandwidth is > new and I am looking for a quick documentation file which describes > what are the knobs and how to use it. Did not find any in > Documentation/cgroups/. Is there any documentation available? Its written in C, its at kernel/sched/fair.c ;-) > I am assuming that max are being specified for groups in some absolute > quantity. That is fine. It will not still be max %, as again for % you > need fixed number of entities at any level and that's not the case with > tasks. > > Minimum for one group (max for everyone else) will also only work if > task and groups are not at same level. I'm really not seeing this. > I think the only way to get fixed % share is not to put task and group > at same level during system configuration. Still doesn't matter, like said, its all runnable based. If a group has 0 runnable entities it doesn't exist (more or less).