VMWARE iSCSI datastore performance

[PTVMWARE]

I have 7 ESX 4.0 U1 hosts running with 2 backend HP 2012i iSCSI storage systems. Using Veeam monitor, i am not able to see any performance data related to Disk I/O. Is there anything i am missing here? My daily sample (5 minutes) and weekly sample (30 minutes) setting in my vCenter is set at statistical level 2.

[sixth]

I see the same issue on my iSCSI shared storage system. EQL PS4000 the volume does not show any performance or data usage on the volume. Local datastores show up fine. Any ideas?