Patent ID: 7290259

Claim:
A virtual computer system, comprising: a plurality of virtual computers operating on a physical computer having one or more CPUs and a main memory device; a hypervisor; a storing section for storing contents of a plurality of actions for changing physical resources allocated to virtual computers judged as having high loads by a load monitor which monitors load conditions of said virtual computers; and means for implementing said plurality of actions sequentially and for conducting physical resource allocation according to contents of said actions that are deemed most effective in lowering loads of said virtual computers, wherein said hypervisor comprises: said load monitor for monitoring load conditions of said virtual computers based on load conditions of said main memory device a reallocation section for providing an output for dynamically changing allocation of physical resources to said virtual computers based on said load conditions monitored by said load monitor and a controller for controlling physical resource allocation to said virtual computers based on load conditions monitored by said load monitor, and for demanding reallocation in response to said output from said reallocation section, and wherein a result of implementing said actions is fed back to said means for implementing to permit selection of actions that are most effective.