On Fri, 14 Jun 2002, Greg A. Woods wrote: > That's irrelevant from PostgreSQL's point of view. There's no sure > way to tell the postgresql process(es) to make the on-disk database > image consistent before you create the snapshot.
if it's pg 7.1+ then it has write-ahead-logging, and the on-disk state /is/ guaranteed to be recoverable to a consistent state. in which case snapshot+backup of snapshot is a valid way to backup pgsql. also, i think pgsql pre-7.1 / without WAL by default does fsync() after every transactions. so, while still racy, likelyhood is you will get a decent backup on a not too heavily used db. (but no guarantees). --paulj