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:
May. 30, 1995
Filed:
Sep. 17, 1992
Dennis R Escola, Gilroy, CA (US);
Steven D Gerdt, San Jose, CA (US);
Barrie N Harding, San Jose, CA (US);
Lloyd R Shipman, Jr, San Jose, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A data storage system is described which provides for fault tolerance during execution of a media maintenance program on a selected track of nonvolatile data storage. Checkpoint data for the media maintenance program is stored in nonvolatile storage prior to writing control information on the selected track during the execution of the media maintenance program. The checkpoint data includes an address in the media maintenance program for resuming execution in the event that the media maintenance process is aborted. The checkpoint data is read from the nonvolatile storage area after media maintenance has been aborted by a fault, typically after power has been reapplied to the system. The execution environment for the media maintenance program is restored by storing data in the RAM of the controller which duplicates the control data needed by the particular segment of the media maintenance program which will be restarted. After the environment is restored, the execution of the media maintenance program resumes at the address in checkpoint data stored prior to writing the control data on the selected track.