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:
May. 04, 1999
Filed:
Aug. 09, 1996
Lorraine Maria Herger, Kingston, PA (US);
Kwok-Ken Mak, Wappingers Falls, NY (US);
Kenneth Blair Ocheltree, Ossining, NY (US);
Tu-Chih Tsai, Yorktown Heights, NY (US);
Michael Edward Wazlowski, Carmel, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of maintaining cache coherency in a computer system including two or more processors sharing information, the processors coupled by two or more interconnects to a memory such that the processors are not directly coupled to the same is disclosed interconnect is disclosed. The method of maintaining cache coherency includes the steps of: accessing and sharing, by a first processor and a second processor, information from the memory and setting path indicators in directories associated with at least two of the interconnects on a respective first and second access path to the memory, and storing the information in respective associated first and second caches; and writing a new value to the information, by a writing processor sharing the information, the writing step including the steps of: invalidating other copies of the information via the path indicators; acquiring exclusive access to the information by changing the path indicators to an exclusive state; and writing the new value to the information, in response to the acquiring step.