Methods and system for detecting data loss in a hierarchic data storage system
US5572661A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 5, 1994 |
| Grant date | Nov 5, 1996 |
| Priority date | — |
| Expiry date | Oct 5, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/20
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Data loss is selectively tracked within a hierarchic data storage system having multiple storage disks that define a physical storage space. The physical storage space is mapped into a first virtual storage space which presents the physical storage space as multiple RAID areas that store data according to various RAID levels, such as RAID Level 1 (mirror redundancy) or RAID Level 5 (parity redundancy). Individual RAID areas extend across multiple storage disks and include a region of physical storage space on individual storage disks. The first virtual storage space is mapped into a second virtual storage space which presents the physical storage space as multiple virtual blocks. The RAID areas are monitored to detect data loss. Upon detecting data loss within a region of a RAID area, this first region is marked as invalid. Upon detecting data loss within a second region of the same RAID area, the data storage system will determine the extent of data loss. If the data loss is comparatively minor, the data storage system will identify the virtual block that is mapped onto the portion of the second region and mark it defective. The address of the virtual block is stored in a virtual …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.