Invalidation of entries in a translation table by providing the machine a unique identification thereby disallowing a match and rendering the entries invalid

摘要

A virtual computer system having a translation lookaside buffer which converts a virtual address to a real address comprises a register (VMNR) for storing the identification number (VMID) of a currently running virtual machine, the translation lookaside buffer having a bit for holding the VMID and a comparison circuit which compares the VMID held in the bit with the VMID provided by the VMNR and predicates the success of conversion from a virtual address to a real address on the basis of a matching result of comparison, a management table for holding data indicative of VMIDs used to define virtual machines which have run up to the current time point, and a control circuit which, when an invalidation command for the translation lookaside buffer is issued during a run of a virtual machine, selects an unused VMID as first information for defining the running virtual machine on the basis of the contents of the management table and sets the selected VMID in the VMNR.