System and method for ordering commands in an automatic volume placement library

Patent 5418971 Issued on May 23, 1995. Estimated Expiration Date:

May 23, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

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Inventor

Carlson, Wayne C.

Application

No. 871379 filed on 04/20/1992

US Classes:

710/24, By command chaining360/92Tape in container

Examiners

Primary: Bowler, Alyssa H.
Assistant: Davis, Albert W. Jr.

Attorney, Agent or Firm

Schecter; Manny, Dillon; Andrew J.

International Class

G06F 012/00

Abstract

A system and method of sequencing commands for operation of a volume positioning mechanism in an automated library is taught. The automated library has a plurality of volumes, a plurality of racks for storing the plurality of volumes and at least a first drive unit for recording data to or reading data from a volume mounted thereon by the volume positioning mechanism. Exogenous requests for data stored to the volumes or for storing data to volumes are received from time to time by the library. Each exogenous request for data in a volume is utilized to generate at least a first command for execution by the volume positioning mechanism. Commands as generated are stored in a command queue having a queue input level, a queue output level for the next scheduled command for execution and allowing a plurality of intervening levels. With each introduction of a new command to the command queue, the command queue is reordered with a goal of improving time to dispatch for execution of high priority commands.