Intelligent caching scheme for streaming file systems
US7574580B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 2005 |
| Grant date | Aug 11, 2009 |
| Priority date | — |
| Expiry date | May 16, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2516
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A Hard Disk Drive (HDD) is provided two FATs and two cluster sizes, a regular cluster and a “Supercluster”. In one example, each Supercluster is the size of four regular clusters. A second Supercluster FAT is added (FAT2) which works in a similar manner to the original FAT (hereinafter FAT1), but instead points to the next Supercluster in the chain. Since there are far fewer Superclusters than clusters, the Supercluster FAT (FAT2) can be stored in a cache memory. When data is streamed to and from the hard drive, it can be streamed to Superclusters and no seeks on the HDD to a FAT are required, as the FAT2 is cached in memory. Access time to and from the hard drive is decreased. The original cluster configuration is still supported. During lulls in system operation, the FAT2 data may be written to the drive and moreover, FAT1 data created and “flushed” to the hard drive. Thus, if the HDD is read by a standard computer system, it will recognize the regular clusters from the FAT1 table in a transparent manner (and ignore the FAT2 table).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.