Hi everybody, we have an oracle 8i in a Sun Blade 100 with 512MB of RAM.
Recently we started another instance in the database and noticed that the performance of the machine became degrade...
We are not sure if is this instance is the responsable of the perfomance degrade, so we need some tips to know what's going on...
I use the top utility to check out the process size and sometimes some oracle proceses takes 30% of the CPU usage....
Is there a way I can improve performance in my server?
Any document to read about or utility?
thanks in advance for any tip..
The most likely cause will be the fact that you dont have enough RAM to hold both instances completely in memory, so it will probably use the swap file which can seriously hamper performance. If this is the case reduce the size of your buffer caches and SGA to try and avoid the swap file, or add more RAM as 512MB isnt really enough for 2 instances.
The other likely cause will be the fact that the server just doesnt have enough CPU power to run 2 instances under heavy load. How many CPUs do you have, if it only has 1 then youll get a lot of process swapping under load.
Other causes would be poor disk configuration i.e. a lot of contention on a particular disk or a poorly optimized database i.e. missing indexes etc.