Using extents of indirect blocks for file mapping of large files
US9542401B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 2012 |
| Grant date | Jan 10, 2017 |
| Priority date | — |
| Expiry date | Nov 12, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/128
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Large files in a file system are mapped by extents of contiguous indirect blocks in order to reduce the time for read or write access to the large files while allowing allocation of data blocks one at a time. The inode of a file includes an indication of whether file mapping metadata of the file includes either an extent of contiguous indirect blocks or a tree of blocks. In a preferred mapping scheme, an inode contains an array of block pointer entries, and each entry includes a flag indicating whether the block pointer is pointing to either an extent of indirect blocks or a tree of blocks. For sharing of data blocks between files, the block pointer fields of the indirect blocks each contain an ownership flag indicating whether the pointed-to block is shared or not.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.