Support for prompt creation of target-less snapshots on a target logical device that has been linked to a target-less snapshot of a source logical device
US10635542B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 2017 |
| Grant date | Apr 28, 2020 |
| Priority date | — |
| Expiry date | Dec 18, 2037 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2201/84
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
To allow prompt creation of a target-less snapshot of a target logical volume, after the target logical volume has been linked to a target-less snapshot to allow host access to the target-less snapshot, and prior to all the tracks of the target logical volume being defined with regard to data from the target-less snapshot, a target device sequence number is maintained for the target logical volume, and incremented each time a target-less snapshot is linked to the target logical volume. A target track sequence number is maintained for each track of the target logical volume, and updated each time target-less snapshot data is moved to the corresponding track. The target device sequence number and target track sequence numbers are compared prior to performing host I/O operations directed to the target logical volume to ensure data correctness on a track by track basis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.