Comment 0 for bug 1907964

Problem:
       When backups are created with backend / driver being ceph, there currently
       is no way to enable the image feature, 'fast-diff'.
       Fast-diff adds another property to the object map, which makes it much faster to generate diffs
       between snapshots of an image, and the actual data usage of a snapshot much faster.

Features applied to backup images unfortunately do not depend on the regular cinder settings,
each feature is handled explicitly by a config option. Following this approach support for
EXCLUSIVE_LOCK and JOURNALING was implemented with https://review.opendev.org/c/openstack/cinder/+/413178