I find that the disk IO performance of vm instances on iSCSI(sharedmountpoint) primary storage is worse than that on NFS primary storage.
When I use a single hdd and create a NFS share as primary storage,the disk IO performance is pretty good. But when I use the same hdd and create a iSCSI lun as primary storage,the disk IO performance is lower than NFS. I think the disk IO performance of iSCSI should be better than NFS.
