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. 06, 2004
Filed:
Nov. 14, 2001
William A. Brant, Boulder, CO (US);
William G. Deitz, Niwot, CO (US);
Michael E. Nielson, Broomfield, CO (US);
Joseph G. Skazinski, Berthoud, CO (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Adaptive write policy for handling host write commands to write-back system drives in a dual active controller environment. Method for adaptive write policy in data storage system, where data storage system includes host system connected to primary controller and alternate controller. Controllers are coupled to system drive that includes one or more disk storage devices. Primary is connected to first memory and alternate is connected to second memory. Primary and alternate manage data storage system in dual-active configuration. Primary controller receives host write command from host system and write data request includes host write data. When system drive is configured with write-back policy, primary determines whether host write command encompasses an entire RAID stripe, and if so, primary processes host write command in accordance with write-through policy. Otherwise, primary processes command in accordance with write-back policy. Reduces amount of host write data that has to be mirrored to alternate controller.