[eru]

Basically any copy-on-write filesystem should give you snapshots as described in the article for 'free'?

And you can get the over-commitment they describe in their point 1 by just putting the users on the same file system with some per-user quota?

[XorNot]

"any" yes their honestly aren't that many and I'm not aware of any which are as available and battle-tested as ZFS. It's been decades at this point and it's a well-proven, capable filesystem.