filosophizer, it is impossible to teach someone the job over the net. funksen has given you some useful pointers already but if you lack the basics to even understand what he is telling you we can't help you. How to benchmark I/O is learned by understanding how storage technology works, how Unix kernels work, how disks are accessed, by which strategies relational databases (in your case Oracle) optimize disk access and probably some other areas of competence you seriously lack.

To learn all this funksen has probably read several books, a lot of documents plus had some years of experience. How is he supposed to transfer this accumulated amount of knowledge to you here in a few articles? This is impossible.

It is not ill will from our side, but there is probably only one way for you: learn starting from the basics, the same way as he did. Over time you will arrive at the same point as funksen, but neither without effort nor in short time. It took him some years of experience and it will take you the same time to know what he knows.

You come across like a first grader, eager to solve math problems involving advanced calculus and now expect the teacher to tell you how to solve it. In order for you to understand his explanation he would have to explain so many things which in turn will need explanation too, etc., ad infinitum, that you are probably best off pursuing a sound education in systems administration. This, alas, is beyond our scope here.

To finally answer your question:

No, not right. It depends. It depends on so many things you can only find out by first benchmarking the system and then interpreting the values produced by these benchmarks that an answer is simply impossible.

It is not even clear your system is really I/O-bound as you claim: how have you analyzed that and by applying which methods did you arrive at this conclusion? Have you run filemon? vmstat? iostat? What is the OS level (different AIX versions need different tuning parameters)? What is the contents of "/etc/tunables/lastboot"? Which size is the SGA? What is the cache hit/miss statistics in Oracle?

The answers to all these (and a lot more) questions are (or could be) factors if it comes to the I/O-performance of a database. Given the info you have presented until now we could as well toss a coin and answer "friday".

bakunin