hi
i tried starwind on windows as iscsi server.. its quite bad
suggest you build a linux server with scst on it, as the target. and connect from windows host with iscsi
you should get at least 2GB/s on ISCSI, and 3.5GBs on SRP. IPOIB is much slower in performance than SRP
also datagram vs connected mode with 56K MTU rather than the max 4096 MTU in connected mode will likley improve things.