Options for growth

Due to the fact that we are growing out of our current system (PostgreSQL on 
PCs) we are looking for ways to expand and one of the suggestions has been to 
toss PostgreSQL in favour of Oracle with Remote Access Cluster (RAC) 
software.  The theory is that you can just plug machines into the cluster if 
the database appears to be straining and they automagically take over some of 
the load.  Not knowing much about it I can only argue about price and source 
code availability.  The first has some value but the second is harder to 
argue without knowing about RAC.  Is it really as simple as it sounds or 
would we just be giving up the other two for a new set of problems.

My idea is to create a new middleware layer that allows me to split things up 
based on various criteria without changing my application.  RAC sounds like 
it does that at the database/SQL level.  Does it?

We are also looking at hardware solutions, multi-CPU PCs with tons (24GB) of 
memory.  I know that memory will improve access if it prevents swapping but 
how well does PostgreSQL utilize multiple CPUs?

And finally, if you had your dream machine to run on, what would it be?  We 
are also looking outside of PC hardware but we are concerned about not having 
access to that nice, cheap, generic hardware for when we need to grow again 
or for redundant backup.

Thanks for any tips and suggestions.

-- 
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
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