Efficient scavenging of data and metadata file system blocks
US9430492B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2013 |
| Grant date | Aug 30, 2016 |
| Priority date | — |
| Expiry date | Jan 18, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/185
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An improved technique involves identifying the location of backed free blocks, i.e., blocks within an upper deck file system that have been provisioned from storage devices of a data storage system to a lower deck file system, allocated from the lower deck file system to the upper deck file system, and later freed from the upper deck file system. A storage processor accesses a set of data structures that identifies backed free blocks as opposed to free blocks that have not been written into and thus do not correspond to any allocated blocks in storage. Once the storage processor identifies the backed free blocks, the storage processor frees each block in the lower deck file system from which the respective backed free block was allocated. The storage processor then updates the set of data structures to indicate that the respective backed free block is now simply a free block.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.