Description of problem:

Regarding bug #1440230 and the temporary fix (https://github.com/oVirt/vdsm/tree/master/vdsm_hooks/diskunmap) for the time being, there is a problem with oVirt Node NG releases. They lack this vdsm hook. So a node with Cinder/Ceph combo is unable to unmap freed space and will eventually suffocate in no space left on the core Ceph storage.


Version-Release number of selected component (if applicable):


How reproducible:

In a Ceph backed VM delete a file and fstrim the filesystem.

Steps to Reproduce:
1. within the VM: dd if=/dev/zero bs=1M of=/bug_testfile count=1024
2. note size increase of the image in Ceph
3. within VM: rm /bug_testfile && fstrim /
4. note size decrease of the image in Ceph

Actual results:

The size will not decrease.

Expected results:

The size should decrease.

Additional info: