Hi Currently <blkiotune> in domain xml allows only to set cgroups weights blkio.weight or blkio.weight_device I see from https://www.kernel.org/doc/Documentation/cgroups/blkio-controller.txt that cgroups also allows throttling policies settable via blkio.throttle.read_bps_device - blkio.throttle.write_bps_device - blkio.throttle.read_iops_device - blkio.throttle.write_iops_device these AFAIK are not the ones set via <blkdeviotune> which need to be applied to individual virtual disks. are there any plans to allow libvirt to make use of the cgroup throttling? it looks to me it could make life simpler by assigning a bandwitdh limit to a domain without having to partition it among its multiple virtual disks. Assigning a limit to the domain is useful from a host resource management perspective, while having to dictate how guests use their individual disks is not, I think. -------------------------------------------------- regards, Edoardo Comar WebSphere Application Service Platform for Networks (ASPN) ecomar(a)uk.ibm.com +44 (0)1962 81 5576 IBM UK Ltd, Hursley Park, SO21 2JN Unless stated otherwise above: IBM United Kingdom Limited - Registered in England and Wales with number 741598. Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU