As discussed in the links I posted there no or very little performance gains....
SV from VMware states:
Re (2): RDMs are not meant to "buy" performance, so that should not be a factor in choosing them. RDMs are needed for 2 very distinct things: :smileyinfo: using advanced SAN functions/SAN aware apps inside VMs (ii) MSCS clustering across boxes and N+1 clustering. The third less likely reason is if you want to attach multiple terabytes of storage to a VM.
Re (3): s/w iscsi initiator inside a VM will suffer from VM networking overheads. These overheads cannot logically be lower than a s/w iscsi initiator in the VMKernel. So I would choose the latter.
Re (1): Use this!
If you want to optimize for MSSQL, you may choose to create a 'thick' or 'eagerzeroed' VMDK instead of the default 'zeroedThick' VMDK that VI3 gives you. You can refer to the vmkfstools usage guide in server config guide on the differences between (and implications of) thick, zeroedthick and eagerzeroedthick disk formats. All that said, I would just use the default: zeroedthick. This is because zeroedthick has a slight performance overhead on first write to a previously unwritten file block. There is no difference between the formats on subsequent writes. Defaults are a good thing.
