Synchronization and resynchronization of loosely-coupled copy operations between a primary and a remote secondary DASD volume under concurrent updating
US6578120B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1997 |
| Grant date | Jun 10, 2003 |
| Priority date | — |
| Expiry date | Jun 24, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F11/2087
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for assuring consistency between a primary volume and a remote secondary volume wherein a host CPU manages track-to-track transfers using loosely-coupled, storage control unit mediated data paths. The method includes initial volume synchronization in which concurrent updates to primary tracks are serialized by the copy progression at the secondary volume according to address. The method further includes volume resynchronization in the event of extrinsic error, fault, or the like in which bit maps and timestamps are used to determine the status of primary tracks either lost while in flight to the secondary volume or updated during a volume suspension interval. The bit maps and timestamps preserve the most recent version copy order of the tracks on the secondary volume. CONCURRENT UPDATING
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.