On Tue, Feb 28, 2012 at 11:00:21PM +0100, Peter Zijlstra wrote: > 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 ;-) /me does not know enough of scheduler code to parse it fast. But now I found Documentation/scheduler/sched-bwc.txt to explain what max bandwidth control is. > > > 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. Assume I have following hierarchy. root / | \ Tasks G1 G2 Assume I have given upper limit of 20% to G1. (period=50ms, quota=10ms), then it still does not gurantee the minimum bandwidth for G2. If I upper limit G2 also, then I am assuming it just gives minimum gurantee for any tasks in root. (Right now I am assuming just 1 cpu in the system for simplicity). So to get a minimum % bandwdith gurantee for G2, I shall have to move "Tasks" in a children group. Now both upper limit/proportional weight on G3 will help to determine minimum % share of G2. root / | \ G3 G1 G2 | Tasks Please correct me if I have understood the whole thing wrong. Thanks Vivek _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/containers
