Alvaro Herrera <[EMAIL PROTECTED]> writes: > My idea was to move relminxid to a new pg_class_nt non-transactional > catalog in 8.3, but we certainly need to give a solution for the problem > in 8.2.
Didn't we pretty much shoot down the idea of a nontransactional extension catalog as being not worth the trouble? > I don't remember why I concluded that we were safe against this > problem, but you are right that we aren't. I think there may be another set of issues here too: what about PITR? As things stand, neither hint-bit settings nor FrozenXID replacement are guaranteed to get propagated to a PITR slave. We don't propagate CLOG truncation to a slave either, which means that to some extent it'd have the ability to re-set hint bits for itself after coming up. This isn't bulletproof though; most obviously in the case where the PITR replay (or hot-slave lifespan) exceeded 4G transactions. Can we fix it so it's sufficient to propagate FrozenXID replacement to the slave? If we have to turn hint-bit setting into a logged operation, that *will* be expensive. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend