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:
Apr. 14, 2009
Filed:
Nov. 03, 2006
Jonathan J. Dement, Austin, TX (US);
Roy M. Kim, Austin, TX (US);
Alvan W. NG, Austin, TX (US);
Kevin C. Stelzer, Austin, TX (US);
Thuong Q. Truong, Austin, TX (US);
Jonathan J. DeMent, Austin, TX (US);
Roy M. Kim, Austin, TX (US);
Alvan W. Ng, Austin, TX (US);
Kevin C. Stelzer, Austin, TX (US);
Thuong Q. Truong, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A system and method for reducing store latency in symmetrical multiprocessor systems are provided. Bus agents are provided which monitor reflected ownership requests (Dclaims) to determine if the reflected Dclaim is its own Dclaim. If so, the bus agent determines that it is the winner of the ownership request and can immediately perform data modification using its associated local cache. If the bus agent determines that the reflected Dclaim does not match its own Dclaim, it determines that it is the loser of the ownership request and invalidates the corresponding cache line in its own local cache. The loser bus agent may then send a Read With Intent to Modify request to obtain the data from another cache and place it into its own cache for modification. These operations are performed without the need for a Kill request and without having to perform retries of a losing ownership request.