Re: [libvirt] [PATCH 2/2] qemu: amend existing table of device weights

On Tue, Nov 29, 2011 at 02:11:44PM -0700, Eric Blake wrote: > Prior to this patch, for a running dom, the commands: > > $ virsh blkiotune dom --device-weights /dev/sda,502,/dev/sdb,498 > $ virsh blkiotune dom --device-weights /dev/sda,503 > $ virsh blkiotune dom > weight : 500 > device_weight : /dev/sda,503 > > claim that /dev/sdb no longer has a non-default weight, but > directly querying cgroups says otherwise: > > $ cat /cgroup/blkio/libvirt/qemu/dom/blkio.weight_device > 8:0 503 > 8:16 498 > > After this patch, an explicit 0 is required to remove a device path > from the XML, and omitting a device path that was previously > specified leaves that device path untouched in the XML, to match > cgroups behavior. > ACK.