Well, pg being a multi-process architecture, on a 64 bit system you get
the advantages of extra memory for cache all day long. I don't thing a
2gb mem limit/backend is not a wall people are hitting very often even
on high end systems. Performance wise, 32 vs. 64 bit is a tug of war
between extra registers & faster 64 bit ops on one side vs. smaller
pointers and better memory footprint on the other.
Note I am assuming Opteron here where the 32/64 performance is basically
the same.
Merlin
That being said, from what I'm hearing it may be moot because
it's probably best to run postgres as 32 bit on a 64 bit operating
system performance wise.
Oh? why's that then?
/D