Re: [libvirt] [PATCHv4 3/4] blkiotune: add interface for blkiotune.device_weight

From: Hu Tao <hutao(a)cn.fujitsu.com&gt; This adds per-device weights to <blkiotune>. Note that the cgroups implementation only supports weights per block device, and not per-file within the device; hence this option must be global to the domain definition rather than tied to individual <devices>/<disk> entries: <domain ...> <blkiotune> <device> <path>/path/to/block</path> <weight>1000</weight> </device> </blkiotune> .. This patch also adds a parameter --device-weights to virsh command blkiotune for setting/getting blkiotune.weight_device for any hypervisor that supports it. All <device> entries under <blkiotune> are concatenated into a single string attribute under virDomain{Get,Set}BlkioParameters, named "device_weight".