CPU for virtualization (VirtualBox)

[Solaris17]

It's up to the host system.

This. Its a common misconception even among jr sysadmins that you are assigning physical cores. You are not. the definition between all type 1's (proxmox, hyper-v, esxi etc) is "vCPU" the underlying schedulers are doing the rest.

No need to physically gimp and use p core only.

In this case Virtualbox is a type 2. It is using the host OS to manage all hardware interfacing. So the performance impact is theoretically linked to how well your OS handles hardware scheduling and the other things that are running on that OS.

 

[qubit]

Doesn't matter. You can create virtual machine even without VT-d but you won't be able to access PCI devices. If you don't know / understand what it is, you won't need it. I don't believe VirtualBox even supports it. Hyper-V, xen, ESXi, kvm et al do but you need to be more than hobbyist to use them.

Well, it depends on what he uses his VMs for too, so it was worth pointing out.