On Fri, 21 Dec 2007, David Cotter wrote:
In order to access that 32 Gigs do I have to use 64 bit OS and PG?
Yes. You'll be tormented by various things being limited at 2-4 GB on a 32 bit one.
Is there any reason not to use a 64 bit?
The only systems I have running 32 bit are because they rely on some closed-source component where I only have that version available. There are some wrapper libraries available to work around some of these situations. Generally, if you're only dealing with open source software, you should be able to get everything running in 64 bits.
With a 32-bit version of PG can the 32 G of RAM be used for caching?
Yes, but you will have to tune things yourself and ignore a lot of the PG folklore aimed at earlier versions+smaller machines. I've collected some guidelines for your sort of situation at http://www.westnet.com/~gsmith/content/postgresql/ ; the first article there suggests how to get the database server to use all your RAM usefully, while the second points out some potential issues with the fact that by default, your Linux installation may be caching >1GB worth of writes, which can cause some performance issues when you have a checkpoint.
-- * Greg Smith gsmith@xxxxxxxxxxxxx http://www.gregsmith.com Baltimore, MD ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
