Hm, I think the problem is on the ESXi side...

IOMETER latency depends from CPU load of ESXi host
For examle:
0% CPU load = 0.25 ms latency (4000 IOPS)
80% CPU load = 0.5 ms latency (2000 IOPS)

We have Free StarWind 6 iSCSI target + Server 2012 + ESXi 5.1 + 10 Gbit LAN Storage configuration: 2xXeon E5 2609 + 192 GB RAM RevoDrive 3 480 GB PCI-E SSD Card Intel X540 10 GBit NIC ESXi host configuration: 2xXeon E5 2690 + 384 GB RAM No HDD Intel X540 10 GBit NIC Dell 8024 10 Gbit Switch Tested p...