Ceph » rbd

$ rbd create --size 20M --thick-provision foo
Thick provisioning: 100% complete...done.
$ rbd snap create foo@snap
Creating snap: 100% complete...done.
$ rbd snap protect foo@snap
$ rbd clone foo@snap bar

Parent image: expected result without and with fast-diff:

$ rbd diff foo
Offset    Length   Type
0         4194304  data
4194304   4194304  data
8388608   4194304  data
12582912  4194304  data
16777216  4194304  data
$ rbd diff --whole-object foo
Offset    Length   Type
0         4194304  data
4194304   4194304  data
8388608   4194304  data
12582912  4194304  data
16777216  4194304  data

Clone image: expected result only without fast-diff:

$ rbd diff bar
Offset    Length   Type
0         4194304  data
4194304   4194304  data
8388608   4194304  data
12582912  4194304  data
16777216  4194304  data
$ rbd diff --whole-object bar    # no output, should be the same as above

This is a regression introduced with https://github.com/ceph/ceph/commit/4429ed4f3f4c1902ac3f6dcc17339529d57c1ede in pacific.