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:
Dec. 18, 2007
Filed:
Apr. 06, 2005
Kathirgamar Aingaran, Sunnyvale, CA (US);
Ramaswamy Sivaramakrishnan, San Jose, CA (US);
Sanjay Patel, Fremont, CA (US);
Kathirgamar Aingaran, Sunnyvale, CA (US);
Ramaswamy Sivaramakrishnan, San Jose, CA (US);
Sanjay Patel, Fremont, CA (US);
Sun Microsystems, Inc., Santa Clara, CA (US);
Abstract
A method and apparatus is disclosed for maintaining coherency between a primary cache and a secondary cache in a directory-based cache system. Upon identifying a parity error in the primary cache, a tag parity packet and a load instruction are sent from the primary cache to the secondary cache. In response to the tag parity packet, each tag entry in the secondary cache that is associated with the parity error is invalidated. Upon receiving an acknowledgment of receipt of the tag parity packet, the primary cache functions to invalidate each tag entry in the primary cache that is associated with the parity error. Then, the secondary cache communicates data requested in the load instruction to the primary cache.