Optimizing System Performance Using Spare Cores in a Virtualized Environment

A mechanism for optimizing system performance using spare processing cores in a virtualized environment. When detecting a workload partition needs to run on a virtual processor in the virtualized system, a state of the virtual processor is changed to a wait state. A first node comprising memory that is local to the workload partition is determined. A determination is also made as to whether a non-spare processor core in the first node is available to run the workload partition. If no non-spare processor core is available, a free non-spare processor core in a second node is located, and the state of the free non-spare processor core in the second node is changed to an inactive state. The state of a spare processor core in the first node is changed to an active state, and the workload partition is dispatched to the spare processor core in the first node for execution.