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. 19, 2013
Filed:
May. 29, 2009
Yasuo Watanabe, Machida, JP;
Yasuo Watanabe, Machida, JP;
Hitachi, Ltd., Tokyo, JP;
Hitachi Computer Peripherals Co., Ltd., Kanagawa, JP;
Abstract
A secondary subsystem reads first differential data recorded in a magnetic tape device into a magnetic disk device, and manages such data based on second differential data that was created based on the read first differential data and differential management information. Then, whether differential data exists in partial data is determined based on the differential management information, and, if such differential data exists, the partial data is read into a cache memory, and differential data is applied to the partial data. Meanwhile, if differential data does not exist, the partial data is read into the buffer. Moreover, new full data is recorded by writing the partial data, which was read into the cache memory or the buffer, onto the magnetic tape device in parallel with other read processing.