URGENT! Oracle 8i: how much memory is required?

Hi,

I have a SUN machine running SUN Solaris 2.6. I want to install Oracle 8i and create an istance with a SGA size of X MBytes.
Well, I'm looking for a simple algorithm or table that tell me (with a such SGA) memory required vs. connected users (i.e. simply connected via SQL*PLUS). I know that for one user
I obtain RAM=SGA+Processes, but I don't know ('cause of shared memory) what RAM requires one more user (total 2 users connected)! Another question: why "show sga" command tell me X MBytes of SGA while a tracing with "pmap" command report me 2*X MBytes?
Please GURU, answer me!!!
Excuse me for my English....

Thank you in advance.

   Marco Received on Thu Mar 09 2000 - 04:07:57 CST