Not to much a complex question as usual.
I've been just asked to give some opinion on possible impacts of stuffing more schemas in the same Oracle (10g) instance we have our production system running currently.
That's not exactly a problem. The server isn't overloaded or anything and it will get the proper additional resources it might need for supporting the new schemas.
My observations are of the sort "well, you are going to share resources assigned to that instance", "when one backup kicks in, both systems will be down".
Wonder what I'm missing. When would be absolutely recommended to get separated instances. What would be a normal convention for that? or other tips you guys might have.
Just so you guys know, we are talking about a memory and processor intensive application, with pretty much no I/O for long periods. In a nutshell, we are comparing huge data tables all the time.
Highly appreciate your thoughts.
f.
If you have more than one instance on a single server, you will have some hard time troubleshooting performance issues because the Oracle tools won't be able to see each other's performance logs.
This is why on busy production systems my advice would be "one instance at most per server". I don't have much experience with virtualization in production but if you have the resource to deal with a virtualized environment, you could have one instance per logical server.
On an unrelated note, why would you take the DB offline to perform a backup, especially if it is not an IO intensive system?