Hi Sreec,
1. Before the back-up activity, the Davg/cmd is just about 1.
2. I have Storage Vmotion configured between the two hosts. I tried it before but more less the same. The latency is still high and warnings still show.
3. I'm using ESXi 5.0, however I have changed the path policy from MRU to RR as suggested in some posts in order to improve the latency. But it doesn't help much. Indeed, my system was even down because of the latency. But after I have changed some configurations( change from Broadcom iSCSI adapter to software iSCSI adapter, change iops from 1000 to 3 in Path Selection Policy Device Config etc), now there are only warnings.
Thanks