Unanswered: Running 2 versions of Oracle on a UNIX server
I am about to install oracle 10.2.0.1.0 on a Sun Solars (64bit) server that is already running oracle 8.1.7
My question is after I have installed oracle 10.2.0.1.0 on this server will I be able to create and start an Oracle 10g instance on this same server ( of course they will both have different oracle homes) with ONLY 1GB or RAM available on this server or do I have to request that the RAM be increased? considering the fact that Oracle 10g requires a lot of resources.
Is this a SPARC or x86 system ? Only if you're using x86 system you can install it with your available ram (as described here). I don't believe you will be able to have both instances running with such limited ram. I would request more ram inmediatelly if I were you.
This is one of those questions where it just depends. You can run multiple versions of oracle on a Unix Server. I personally have done it for testing purposes with 1G and less systems. Currently I am running 2 versions on a Windows box with under 1G.
The real question is what these instances are going to be used for. If after you determine, by analysis, that 1G will not be enough then yes you should purchase more memory.
If these are production machines or heavy development will be accessing them, then, as JMartinez posted, I would run to the memory store as fast as you can.