We get left over delta files under /var/lib/one/datastores/0

For some reason we currently have 4 folders containing delta files under /var/lib/one/datastores/0:

drwxrwxr-x 2 oneadmin oneadmin 4096 Oct 10 18:29 1388319
drwxrwxr-x 2 oneadmin oneadmin 4096 Oct 10 18:29 1575669
drwxrwxr-x 2 oneadmin oneadmin 4096 Oct 10 18:29 1611013
drwxrwxr-x 3 oneadmin oneadmin 4096 Oct 10 18:29 1629259

If that folder name is the ID, the VMs are very very old in that case. We are currently creating IDs beyond 2 million. All the same, something refreshed the time stamp over a month ago.

Total size of those 4 folders is 5.1GB.