From mboxrd@z Thu Jan 1 00:00:00 1970 From: Balbir Singh Subject: Re: dm-ioband + bio-cgroup benchmarks Date: Wed, 24 Sep 2008 18:08:05 +0530 Message-ID: <48DA34AD.4040305@linux.vnet.ibm.com> References: <20080919131019.GA3606@redhat.com> <20080922.183651.62951479.taka@valinux.co.jp> <20080922143042.GA19222@redhat.com> <20080924.193414.22923673.taka@valinux.co.jp> Reply-To: balbir@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20080924.193414.22923673.taka@valinux.co.jp> Sender: linux-kernel-owner@vger.kernel.org To: Hirokazu Takahashi Cc: vgoyal@redhat.com, ryov@valinux.co.jp, linux-kernel@vger.kernel.org, dm-devel@redhat.com, containers@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, xen-devel@lists.xensource.com, fernando@oss.ntt.co.jp, xemul@openvz.org, agk@sourceware.org, righi.andrea@gmail.com, jens.axboe@oracle.com List-Id: dm-devel.ids Hirokazu Takahashi wrote: > Hi, > >>> It's possible the algorithm of dm-ioband can be placed in the block layer >>> if it is really a big problem. >>> But I doubt it can control every control block I/O as we wish since >>> the interface the cgroup supports is quite poor. >> Had a question regarding cgroup interface. I am assuming that in a system, >> one will be using other controllers as well apart from IO-controller. >> Other controllers will be using cgroup as a grouping mechanism. >> Now coming up with additional grouping mechanism for only io-controller seems >> little odd to me. It will make the job of higher level management software >> harder. >> >> Looking at the dm-ioband grouping examples given in patches, I think cases >> of grouping based in pid, pgrp, uid and kvm can be handled by creating right >> cgroup and making sure applications are launched/moved into right cgroup by >> user space tools. > > Grouping in pid, pgrp and uid is not the point, which I've been thinking > can be replaced with cgroup once the implementation of bio-cgroup is done. > > I think problems of cgroup are that they can't support lots of storages > and hotplug devices, it just handle them as if they were just one resource. Could you elaborate on this please? > I don't insist the interface of dm-ioband is the best. I just hope the > cgroup infrastructure support this kind of resources. > What sort of support will help you? -- Balbir