I often make snapshots of a ZFS volume (containing AOSP) make some changes (often extracting ZIP files over then top, or running scripts) and then run
diff to see what has changed.
This is really easy with ZFS:
diff /mnt/vol /mnt/vol/.zfs/2017-10-18_snapshot
It takes a very long time when "vol" contains 63GB of mostly small files.
ZFS obviously has the information about which files are different, as the snapshots are Copy-on-Write.
Is there a ZFS-aware diff which can just ask ZFS for the answer?