Help needed with performance...please.

Last week I posted a request for assitance in tuning Pg 6.3.2, or more
specifically, where I could learn more about it.

After much searching I found where to define the maximum number of back
ends. However, I still have not learned anything specific about the flags
that manage memory usage.

Here's what I have:    Dual PPro 200, 64 meg RAM, 128 meg swap,
Linux-2.0.35 w/SMP, PgSQL 6.3.2 on a switched 100 mbit full duplex network.

Realisitically I only need 4 to 8 simultaneous back end processes, yet I am
planning on a maximum of 12 to 16. What I need to know is how to fine tune
memory usage to help improve performance and keep Pg from swallowing all
available memory.

I've read everything I can find on the subject and the most information I
find is the flags to make the adjustments, but there is no information on
what the ramifications of changing these options might be.

Can anyone make some recommendations on what options might work well for the
front and back ends with my configuration? And if you can, would you please
explain what the options do and why they are beneficial? I can look at the
man page and figure out what the options and flags are setting, but that
won't help me to learn WHY setting the buffer count to X instead of default
is better, for example.

Thanks
Greg

PS - My apologies for posting this message to three lists.  I am short on
time, and I need to get this box out of the 'testing/debug' phase and into
'production'. Everything is stable, I just want to make some final
performance tweaks before I put it into production. Thanks again.

Gregory S. Youngblood
ext 2164