FC, iSCSI or NFS for vSphere? It doesn't matter

For real world VMware vSphere usage, it doesn't matter if you're using Fibre Channel, iSCSI or NFS. NetApp and VMware investigated the performance differences between the major front-end protocols under simulated real-world conditions on vSphere 4.1 and found that the differences just aren't that significant. The tests were generic and the findings should apply to most storage arrays, such as those from EMC or Dell.

While 1Gbps Ethernet iSCSI and NFS have slightly lower throughput and higher latency than FC, at 10Gbps the protocols perform almost identically. That's what this in-depth blog post and report from NetApp shows.

While there may be some edge cases that still see an increased performance with Fibre Channel, most production environments would be well served with iSCSI or NFS.

Source: Yellow Bricks