I'm going to drag this into slightly different direction (yeah right - what else can you expect from me?;)
This thread is full of assumptions leading to interesting guesses. Pretty much all of them have their chance to happen and many more exist. Though, there were few suggestions to proceed with rather standard performance troubleshooting. However, OP expressed his interest in silver bullets - "I was just trying to see if anyone can help pinpoint us on areas to focus on as possible culprits". Everything is possible and many things are arguably probable.
This is not to discourage the answers and ideas in the cases that don't really have a clear investigation paths and methods to gather more information. But in this case there is only vague description of a complex system and not a single performance metric collections ("improved significantly" and "in some cases 20X faster" don't count). Any RAC system is quite complex (and 6 nodes cluster is not the least complex) and tuning by silver bullets would traditionally be longer/ more expensive/complex/prone to errors. There are much better investigation paths to take.
My rant is over... please continue. :-) Alex On 3-Apr-08, at 7:44 PM, 조동욱 wrote:
I doubt if OP has a mal-configured network setting. It's possible that 6-node RAC performs poorer than 2-node RAC. But 20X time? No way.If the application access pattern and workload are same, the only culprits are poor interconnect or storage. I recommend to monitor OS level network statistics, configuration and plus, Oracle cluster wait events.Dion Cho
