Esxi + Eternus DX80 iSCSI storage: very slow read speed

[christip]

We have an Eternus DX80 iSCSI storage (with two LUN) attached to a vSphere cluster with 4 ESXi server; we have noticed a very low reading speed against an excellent write speed, trying to read data through an RHEL 5.7 VM with disk on "iSCSI Datastore".

On iSCSI we have two RAID5 combined with two respective LUN; on ESXi side we have two datastore mounted on previous created LUN. On Eternus side we have create a portgroup with two port used in multipath configuration.

We have followed the instruction from Eternus manual and VMware manual but haven't found the right configuration for Eternus or ESXi to reach an appreciable read speed.

Is there anyone who has had this problem that can help us?

Thanks in advance.

Christian

[Bulkas]

we have the same storage on 2x1GB ISCSI in RR and have low perfomance in read/write )) i think its normal for this storage. Additional DE with 7.2k disks is slower that  home storage )

What results you have in perfomance test? (for compare)