Guest execution control system, method and computer process for a

Abstract

A guest execution control system method and computer process for a virtual machine system having a main storage for holding a state descriptor of a guest virtual machine, and a plurality of instruction processors each starting execution of the guest virtual machine by executing an execution start instruction for the guest virtual machine. Execution instruction information in the state descriptor indicating whether execution of the guest virtual machine is to be finished is changed when a state of the virtual machine satisfies a predetermined condition during execution of the guest virtual machine. The execution instruction information is held at an address in the main storage. The guest execution control system includes a circuit which compares an address in the main storage of information being changed with the address in the main storage of the execution instruction information, and informs the guest virtual machine being executed that the execution instruction information has been changed when the address in the main storage of information being changed is the same as the address in the main storage of the execution instruction information. The guest execution control method and computer process performs the comparing and informing operations for the virtual machine system.