I’m using the free tool Crystaldiskmark to do some  I/O comparison between local disk and our filers. On at least one system  (SAN connected), the local disk (6 disks in RAID1) consistently comes out ahead in both read and write. Filer is lightly loaded, and this is on a 56 disk aggregate.   I’m kind of stumped on this one, and would like to know if:

a) Are there any other commonly used benchmarks which I can try with the filers? 

b) This is on a 2G FC SAN.  How much improvement can I expect with 4G or 8G?

Thanks

Suresh