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:
Jul. 18, 2000
Filed:
Sep. 29, 1997
Paul Hodges, Los Gatos, CA (US);
Robert Wesley Shomler, Morgan Hill, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A system and method are provided for coordinating command for updating and reconstructing data in an array of storage devices connected to a computer system when multiple initiators issue commands. Sets of data blocks and corresponding parity blocks are arranged on a plurality of storage devices, such that a data block can be reconstructed using a set of data blocks and at least one parity block. When a new data block is written to the disk drive, a corresponding old parity block is write updated with an updated parity block. When reconstructing an unavailable data block an initiator issues a read command to each storage device having a data block or a parity block used for reconstructing the unavailable data block. Each read command is enqueued on a command queue for each storage device in a priority order coordinating each read command with any write update command for the same block so that a new data block and an old parity block are not read as part of the same parity stripe and vice versa.