ostree prune [Options...]
This searches for unreachable objects in the current repository. If unreachable objects are found, the command delete them to free space. If the --no-prune option is invoked, the command will just print unreachable objects and recommend deleting them.
Only display unreachable objects; don't delete.
Only compute reachability via refs.
Specify a COMMIT to delete.
All commits older than DATE will be pruned. The format of DATE is the same as that accepted by GNU date utility - for more information see info date.
Only traverse DEPTH (integer) parents for each commit (default: -1=infinite).
This option may currently only be used in combination with --delete-commit. Previous versions of ostree silently accepted the option without that, and ignored it. However, there are desired use cases for pruning just static deltas (while retaining the commits), and it's likely at some point this option will be supported for use cases outside of just --delete-commit.
$ ostree prune
Total objects: 25627 No unreachable objects