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:
Feb. 07, 2006
Filed:
May. 07, 2001
Lawrence Yium-chee Chiu, Cupertino, CA (US);
Windsor Wee Sun Hsu, Sunnyvale, CA (US);
Honesty Cheng Young, Saratoga, CA (US);
Lawrence Yium-chee Chiu, Cupertino, CA (US);
Windsor Wee Sun Hsu, Sunnyvale, CA (US);
Honesty Cheng Young, Saratoga, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method, apparatus, and article of manufacture provide the ability to maintain cache in a clustered environment. The cache is maintained in both a primary and secondary node. When data is requested, a symbolic list in a cache directory is examined to determine which node's cache contains the requested data. If the symbolic list indicates data is not currently in cache of any node, any node may be used as the secondary node. However, if an original primary node maintains the data in cache, the original primary node is selected as the secondary node. Once a new write I/O operation is performed, the symbolic list is updated to provide. To install a new node, after applying for cluster admission, symbolic information and a modified track list is requested. The modified track list is merged with new symbolic entries and the new node then broadcasts its availability to the cluster.