Several reasons. Snapshots, Cloning, Replication. Customized record sizes per database. There are many good reasons to run PG on ZFS and almost everyone does. Except the MySQL/Linux crowd. The rest of have moved on from the pain of the well worn FS's of the distant past.
Very interesting. For some reason I always thought that no one runs PostgreSQL on ZFS. If it's not a secret, what company uses PostgreSQL on FreeBSD like this?
