Dismiss
The InnovationQ application will be updated on Sunday, May 31st from 10am-noon ET. You may experience brief service interruptions during that time.
Browse Prior Art Database

Two-Level Sector Reallocation

IP.com Disclosure Number: IPCOM000036085D
Original Publication Date: 1989-Sep-01
Included in the Prior Art Database: 2005-Jan-28

Publishing Venue

IBM

Related People

Authors:
Gregg, LE Rubin, BS Spencer, RD [+details]

Abstract

Previously, two distinct methods of handling bad sectors on disks have been used. The first method placed the responsibility in the host computer using the disk drive. If a bad sector should be encountered, it was the job of the controlling software to take recovery action, and then, if required, move data to some other address on the disk. The second method moved the bad sector management to an "intelligent" drive. One typical feature of these disk drives is that the drive includes some "spare" sectors--possibly one or more for each track. A "reassign" command can be issued to the disk and this command will result in some "logical" disk address being moved to another physical location on the disk. This reassignment by the drive involves no further work or bookkeeping by the disk-controlling software.