Methods and apparatus for creating a branch file in a file system
US8250035B1 · kind B1 · utility
16Cited by
20References
36Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 30, 2008 |
| Grant date | Aug 21, 2012 |
| Priority date | — |
| Expiry date | Feb 25, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/128
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Embodiments of the invention relate to maintaining reference counts in a file system to track when a block is available to be freed. When a snapshot copy of a file is created, rather than copying all the blocks of the file for the snapshot copy, the snapshot inode is given pointers to the blocks of the file. Rather than updating the reference counts for all these blocks to indicate that they are now in use by more than one file, the update of reference counts for at least some of these blocks may be deferred until a later time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.