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:
Aug. 21, 2007
Filed:
Dec. 04, 2003
Curt Lee Cotner, Gilroy, CA (US);
Brian K. Howell, San Jose, CA (US);
Jeffrey William Josten, San Jose, CA (US);
James Willis Pickel, Gilroy, CA (US);
Curt Lee Cotner, Gilroy, CA (US);
Brian K. Howell, San Jose, CA (US);
Jeffrey William Josten, San Jose, CA (US);
James Willis Pickel, Gilroy, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A shared memory device called the Coupling Facility (CF) is used to record the indoubt transaction entries for each member of the database cluster, avoiding the CPU cost and elapsed time impact of persisting this information to disk (either via a log write or a relational table I/O). The CF provides full read/write access and data coherency for concurrent access by all the members in the database cluster. At any given point in time, the CF will contain the full list of indoubt transactions for the entire database cluster. CF duplexing is used to guarantee the integrity of the CF structure used for the indoubt list. In the event of complete loss of both CF structures (which will not happen except in major disaster situations), data sharing group restart processing can reconstruct the CF structures from the individual member logs.