DB Performance

I need to find a way to increase performance on my server.

We are currently using postgres as a back-end to our web-based
corporate wide application. The application is used for everything
from collecting large amount of data, updating current data and
creating large reports based on this data. At this point we have
about 3000 users on the system and this is going to grow rapidly.

We are running apache, mod-perl, sendmail, and postgres on our
server. The machine is a dual 900Mhz processor with 2 gigs of ram,
and fast 10k raid drives.

I have set the shared memory on the machine to 512MB.

Postgres is configured as follows:

sort_mem = 128672
shared_buffers = 60800
fsync = false

We will be purchasing new machines to split off the web server from
the database server.

What else can I do to help performance?
Will a beowulf cluster help to increase performance?

Any suggestions would be greatly appreciated.

Thanks,

Gary
Gary DeSorbo
isasitis(at)uchicago(dot)edu
Cell: 415.606.3857