PURPOSE: To obtain a flexible address conversion system by providing a shared address conversion table of an area shared between respective viertual spaces in corresponding to plural entries of a conversion table, and a means detecting the shared address conversion table from the respective virtual spaces.
CONSTITUTION: In case virtual spaces share some page, an identification name 71 is designated and taken for a key, and a shared address conversion table directory CPD 70 is searched. Then the coincident entry is found, and information on the address 74 in a target shared address conversion table CPGT 150 is obtained. Based on the information each entry 142 in a page conversion table 140 can be generated. Thus the shared page does not need to have the same page address in the respective virtual spaces. Moreover table capacity corresponding to the shared amount suffices in terms of the shared page conversion table, and a small shared table can realize the page sharing control at the high degree of freedom.
ONO MIE
KAGIMASA TOYOHIKO
