Reorganization of striped data during file system expansion in a data storage system
US6499039B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1999 |
| Grant date | Dec 24, 2002 |
| Priority date | — |
| Expiry date | Sep 23, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99955
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
To reorganize a striped file system, data blocks are sequentially moved from storage locations in original data storage to storage locations in an array including the original data storage and additional data storage. If the new striping has the same precedence order as the original striping, then temporary storage is not needed for the block movement. Otherwise, stripes of the data blocks are sequentially moved to a stripe of temporary storage locations, and moved from the stripe of the temporary locations to storage locations in the array. Once a pivot point is reached, however, there is no need to use the temporary storage. Moreover, there is an increasing separation between the read and write pointers. Once this separation exceeds the stripe length, the file system metadata can be synchronized at decreasing intervals and still permit concurrent read access. The number of block transfers between the synchronization points can increase exponentially, and the synchronization points can be aligned with extent boundaries.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.