International Business Machines Corporation

David L Patton

Daniel James Winarski

John Edward Kulakowski

Rodney Jerome Means

Dennis L Willson

Andrew A Gaudet

Joseph C Hartung

An apparatus and method are provided for tracking the number of permanent and temporary errors, and spare sectors used as a result of the errors, on a per disk and per drive basis. During read/write operations, a determination is made as to whether the number of spares used to replace defective sectors on a disk, together with the number of spares used to replace defective sectors during formatting, exceeds a predetermined limit. This limit can be different depending upon the type of disk in use, rewritable or WORM. If the limit is exceeded, diagnostics are executed to ascertain the cause of the excess usage and appropriate corrective action, such as requesting that the disk and drive lens be cleaned, is initiated. Moreovers, an attempt can be made to recover used spare sectors on a rewritable disk.

Detection of overusage of spare sectors in an optical disk

A method for selecting additional data storage media for demount in an idle automated storage library, and an automated storage library and program product therefor are disclosed. The method permits the advanced demount of storage media when one or more of the occupied peripheral storage devices remains inactive for a relatively long predetermined time. Storage media may be demounted to service a pending mount request, provided the peripheral storage devices in which the media are mounted are inactive. A storage medium may also be demounted to create an unoccupied peripheral storage device, even though no mount request is pending, when all of the peripheral storage devices are occupied and one or more of such devices remains inactive for a relatively short predetermined time. In addition, regardless of the existence of a pending mount request or of the occupancy status of the peripheral storage devices, the storage medium in each of the occupied peripheral storage devices remaining inactive for the relatively long predetermined time is demounted and transferred to a storage cell in the library. Thus, during long idle periods, the library will not continue to use the resources of inactive peripheral storage devices. Storage media may also be spun down, but not removed from the disc drive.

Idle demount in an automated storage library

Growing community of inventors

Tucson, AZ, United States of America

David L Patton