Mass storage subsystem and backup arrangement for digital data processing system which permits information to be backed up while host computer(s) continue(s) operating in connection with information stored on mass storage subsystem
US6076148A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 26, 1997 |
| Grant date | Jun 13, 2000 |
| Priority date | — |
| Expiry date | Dec 26, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/1466
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A computer system includes a host computer, a mass storage subsystem and a backup subsystem for backing up information stored on the mass storage subsystem. The mass storage subsystem stores information on a series of tracks. A backup bit map includes a plurality of bits each associated with a respective one of the tracks and indicates the backup status of the track during a backup operation. Initially, during a backup operation, the bits associated with the tracks to be backed up will be set. Generally, the mass storage subsystem transfers information from the track to be backed up in order of the bits in the bit map, and after each track is backed up, it will clear the track's bit. However, when the host is to store information in the mass storage subsystem, it will determine whether the bit associated with the track in which the information is to be stored is set and, if so, enable the mass storage subsystem to back up the track out of turn, and to re-set the track's bit. After the information has been retrieved from the track, the bit associated therewith will be reset, and the host will store the information in the track. This allows the mass storage subsystem to ensure that t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.