vSphere 5 Hardware Version 8 & New vCPU Config for Licensing Trickery
With vSphere 5 comes a new virtual machine hardware version... version 8. The vCPU configuration has changed a bit in the new layout and you can totally see why. When creating a new VM, or editing virtual machine hardware, you can now choose a virtual socket and core allocation to the VM instead of just choosing a "vCPU count".
The amount of vCPU's you can distribute is based on the amount of physical cores available on the host. For instance, I have a single Quad Core Intel chip on each of my home lab servers. That means a VM can be configured with up to 4 available vCPUs in an array of different options. Why would VMware do this?? For application licensing of course! If you have an application that needs some horsepower but is licensed by the socket, no difference if it is virtual or physical, you can get around that by applying multiple cores to a single socket. Think about the money you could save moving from a 12 vCPU VM in vSphere 4 with 12 licensed sockets to a single vCPU socket with 12 cores in vSphere 5!