Hi,
the good thing (IMHO) is to take the iometer test from here: http://communities.vmware.com/message/1989898#1989898
You have ca. 3GB Cache per SP - so you should make the test file bigger (is 8000000=4GB; for you e.g. 20000000=10GB).
With the small test file almost all the ios will come from cache - with the bigger one your disks start to works.
By iscsi it is interesting to know you configuration - you could make some screen shots and paste them here.
Just my 2 cents.
Reg
Christian
