Systems, devices and methods using a solid state device as a caching medium with a read-modify-write offload algorithm to assist snapshots
US10114566B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 2016 |
| Grant date | Oct 30, 2018 |
| Priority date | — |
| Expiry date | Jun 10, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/313
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for offloading RMW operations on a volume of a storage system to a caching medium includes providing an SSD cache, a data structure for managing the SSD cache and cache headers for managing cache lines. The method also includes maintaining cache headers for cache lines corresponding to a same chunk of the volume as a group, creating a snapshot of the volume and, after creating the snapshot, receiving a write I/O operation directed to a portion of the same chunk. The method further includes allocating a new RMW header for the write I/O operation, maintaining the new RMW header in a new group, performing the write I/O operation on the SSD cache, allocating an old RMW header for the group, maintaining the old RMW header with the group and providing a link between the new and old RMW headers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.