Sizing of LARGE databases.

Hello there,

I have a DB that I am attempting to buy "the right hardware" for.

This DB today is about 25GB total, with typical tables in the area of 3GB in
size, and up to about 20 million records per table for the big tables.

Is there any set of recommendations for sizing a DB using PostgreSQL?  (I
have all the docs but have not found anything of any use).

This DB itself will be mostly reads, for a decision system.  However, there
will be a lot more data added in the future where the DB could easily grow
to about 150GB in size, and up to about 60millions records for the large
tables.

My current setup is Linux RH7 w/PostgreSQL 7.0.2, my intention is to build a
large array of Linux Clusters, but I also can not find any documentation on
how if at all PostgreSQL handles a clustered environment.  (Although I did
see something that said you could have multiple "databases" and use a create
view to stich together multiple tables from different DBs in a HOWTO on the
www.kernel.org/LDP I have also noticed that the doc is longer there, and
people who have posted about how to do this on these forums have been told
this method does not work).

Any thoughts would be greatly appreciated.

Michael Miyabara-McCaskey
Email: mykarz@miyabara.com
Web: http://www.miyabara.com/mykarz/
Mobile: +1 408 504 9014