Method and apparatus for migrating resources in a multi-processor computer system

Abstract

Multiple instances of operating systems execute cooperatively in a single multi-processor computer wherein a single physical machine is subdivided by software into multiple partitions, each with the ability to run a distinct copy, or instance, of an operating system. Each individual instance has the resources it needs to execute independently, but instances cooperate to migrate resources from one partition to another. The migration can be initiated and carried out under control of the operating system instances “on the fly” without intervention of the system administrator. Alternatively, a system administrator can reconfigure the system. Resource migration is carried out under a “push” model in which resources are controlled by an owning partition and must be released by that partition before they can be migrated to another partition. In accordance with this model, a first operating system instance which requires a resource must first request the resource from a second instance. In response to this request, the second instance determines whether it can spare the resource, and if so, begins to bring the resource into an idle state. The resource is actually transferred when the second instance stops using the resource.