On Tue, Aug 30, 2011 at 3:55 AM, Zhi Yong Wu <zwu.kernel@xxxxxxxxx> wrote: > I am trying to enable block I/O throttling function in libvirt. But > currently i met some design questions, and don't make sure if we > should extend blkiotune to support block I/O throttling or introduce > one new libvirt command "blkiothrottle" to cover it or not. If you > have some better idea, pls don't hesitate to drop your comments. A little bit of context: this discussion is about adding libvirt support for QEMU disk I/O throttling. Today libvirt supports the cgroups blkio-controller, which handles proportional shares and throughput/iops limits on host block devices. blkio-controller does not support network file systems (NFS) or other QEMU remote block drivers (curl, Ceph/rbd, sheepdog) since they are not host block devices. QEMU I/O throttling works with all types of -drive and therefore complements blkio-controller. I/O throttling can be applied independently to each -drive attached to a guest and supports throughput/iops limits. For more information on this QEMU feature and a comparison with blkio-controller, see Ryan Harper's KVM Forum 2011 presentation: http://www.linux-kvm.org/wiki/images/7/72/2011-forum-keep-a-limit-on-it-io-throttling-in-qemu.pdf Stefan -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list