The point you should take away from this benchmark is that a 3 year old Centos 5 kernel with no tuning, no filesystem tuning and default mdadm options did 100K IOPS or 1GByte/sec pretty much regardless of the benchmark options in use. It just needed enough concurrency to load up the disk. There are many other options on iozone for using different variants of posix IO and threading. I showed the basic options and the mmap option. So with careful tuning you could do IOPS more efficiently, but what I found was very accessible out-of-the-box performance.
