The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 03, 1984
Filed:
May. 29, 1981
Applicant:
Inventor:
Mamoru Hinai, Hadano, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G06F / ;
U.S. Cl.
CPC ...
364200 ;
Abstract
In a data processing system having a buffer storage and operated in a virtual storage system, storage keys including reference bits are retained in a storage key memory one for each predetermined unit of real storage, and reference bits are retained in a reference bit memory one for each predetermined unit of the real storage. Whenever the real storage is referred, the corresponding reference bit of the storage key memory is set, and whenever the buffer storage is referred, the corresponding reference bit of the reference bit memory is set. The reference bit of the storage key memory and the reference bit of the reference bit memory are ORed to produce a true reference bit.