VMware has just released a paper entitled Comparison of Storage Protocol Performance (seen at Scale the Mind and blog.scottlowe.org); maybe this will help deflate some of the too-often repeated speculation that NFS is too slow for VMware ESX.
VMware’s findings match well with what I’ve seen. On some in-house application-specific benchmarking that I’ve done, I actually saw overall better performance with an NFS datastore than with a software iSCSI datastore on the same filer. I won’t get into details, because the benchmark was specific to us (and I’d probably need a lawyer to review the EULAs before “publishing” anything…), but NFS was equal to or slightly faster than iSCSI across the board on this specific set of tests in our specific environment. Given the management and deployment advantages of NFS, that’s huge.
Of course, I wouldn’t recommend basing your whole ESX/NetApp deployment strategy off of one unsubstantiated benchmark-related post on my blog; if you’re using ESX with NetApp storage, I would strongly recommend testing NFS datastores if you haven’t already, though.