From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vivek Goyal Subject: Re: [RFC]QEMU disk I/O limits Date: Tue, 31 May 2011 10:04:02 -0400 Message-ID: <20110531140402.GF16382@redhat.com> References: <20110530050923.GF18832@f12.cn.ibm.com> <20110531134537.GE16382@redhat.com> <4DE4F230.2040203@us.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: kwolf@redhat.com, stefanha@linux.vnet.ibm.com, kvm@vger.kernel.org, guijianfeng@cn.fujitsu.com, qemu-devel@nongnu.org, wuzhy@cn.ibm.com, herbert@gondor.hengli.com.au, Zhi Yong Wu , luowenj@cn.ibm.com, zhanx@cn.ibm.com, zhaoyang@cn.ibm.com, llim@redhat.com, Ryan A Harper To: Anthony Liguori Return-path: Content-Disposition: inline In-Reply-To: <4DE4F230.2040203@us.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org List-Id: kvm.vger.kernel.org On Tue, May 31, 2011 at 08:50:40AM -0500, Anthony Liguori wrote: > On 05/31/2011 08:45 AM, Vivek Goyal wrote: > >On Mon, May 30, 2011 at 01:09:23PM +0800, Zhi Yong Wu wrote: > >>Hello, all, > >> > >> I have prepared to work on a feature called "Disk I/O limits" for qemu-kvm projeect. > >> This feature will enable the user to cap disk I/O amount performed by a VM.It is important for some storage resources to be shared among multi-VMs. As you've known, if some of VMs are doing excessive disk I/O, they will hurt the performance of other VMs. > >> > > > >Hi Zhiyong, > > > >Why not use kernel blkio controller for this and why reinvent the wheel > >and implement the feature again in qemu? > > blkio controller only works for block devices. It doesn't work when > using files. So can't we comeup with something to easily determine which device backs up this file? Though that will still not work for NFS backed storage though. Thanks Vivek