Provided is a virtual computer system capable of finding a configuration whose total sum of memory access delays is smaller than that of a current configuration. In a virtual computer system in which with memory access times within a node and between nodes differing from each other, a hypervisor controls a plurality of virtual processors which execute a process on a plurality of nodes, the hypervisor includes a unit which obtains a total sum of memory access delay time on the virtual machine based on affinity information indicative of a latency or a band of communication between the virtual processors and traffic between the virtual processors, and a unit which reconfigures physical resources based on the total sum of delay time.