Processor core power management in a virtualized environment. A hypervisor, executing on a processor device of a computing host, the processor device having a plurality of processor cores, receives from a guest operating system of a virtual machine, a request to set a virtual central processing unit (VCPU) of the virtual machine to a first requested P-state level of a plurality of P-state levels. Based on the request, the hypervisor associates the VCPU with a first processor core having a P-state that corresponds to the first requested P-state level.