iorate is available on the emc ftp site.

Take a look here: ftp://ftp.emc.com/pub/symm3000/iorate

3+1 will perform great until cache has to destage.

Heavy write application will still run best on 0+1 now and 20 years from now.

The problem with IORATE is that there is too much clutter internally with the code. There are statements within that have to determine what type of IO that you are doing and the percentages of read/writes, etc.. These additional CPU cycles may seem insignifigant but a few microseconds here and there will add up, possibly distorting the results. It would be fine to run though just for comparisons.

The Raid 5 (3+1) that EMC pushes does run well as long as the disks are configured properly. The Raid-S runs fine too.