Partitioned server

We are in the process of implementing an application which will ultimately have about 1500 users. The database (Oracle 10.2.0.2.0 /HP-UX B 11.23) is running on a server with 8 cpu's and 16 gb of memory. The SGA is currently using about 4 gb and the Oracle processes use about 2-3% of cpu. The applications people tell me that we have only about 20% of the expected user community phased into the system (i.e. expect at least a five-fold increase in load on the system).

Now the project managers want to partition the server (HP-UX nPartitions System) so that we will have separate virtual servers, for reporting, development, and test. We would add memory if necessary. Since this is really a zero sum game as far as the number of processors is concerned, is there really any performance benefit to doing this as opposed to running all four Oracle instances on the same server?

Thanks,
Peter Schauss

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