Hi,all At first,I find it is supported that we can define hard performance limits for each volume in doc.openstack.org[1].But only can define hard performance limits for each volume type in fact. Another, the note"As of the Nova 18.0.0 Rocky release, front end QoS settings are only supported when using the libvirt driver.",in fact, we have supported the front end QoS settings when using the libvirt driver previous. Is the document wrong?Can you tell me more about this ?Thank you very much. [1]https://docs.openstack.org/cinder/latest/admin/blockstorage-basic-volume-qos.html Best Regards Rambo -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.openstack.org/pipermail/openstack-dev/attachments/20180910/a9925bb5/attachment.html>