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:
Jan. 03, 1995
Filed:
Nov. 25, 1991
Albert Lui, San Jose, CA (US);
Mark S Walker, Los Gatos, CA (US);
Tandem Computers Incorporated, Cupertino, CA (US);
Abstract
A system and method for ensuring the completion and integrity of data modification operations to a redundant array data storage system and for ensuring the integrity of redundancy values in such a system. The system combines four elements: reliable host processing provided by primary and secondary CPU's with check pointing of operations, so that the secondary CPU can complete initiation of a data modification operation if the primary CPU fails; block-buffering of Write data in a host CPU adapter before transmission of the data to a RAID array controller, so that failure of the host CPU after buffering completes does not interfere with completion of the data modification operation; reliable array processing provided by primary and secondary array controllers with check pointing of operations, so that the secondary array controller can complete a data modification operation if the primary array controller fails; and battery-backup for the power supply to the array controller and the storage units comprising the storage array, or, in the alternative, non-volatile memory in the array controller sufficient to store all data modification operation command information for data records that have not been successfully written to the storage units, for use in subsequent retries.