Method for on-line reorganization of the data on a RAID-4 or RAID-5 array in the absence of one disk and the on-line restoration of a replacement disk
US5390327A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 29, 1993 |
| Grant date | Feb 14, 1995 |
| Priority date | — |
| Expiry date | Jun 29, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2211/1004
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a storage system having a plurality of disks arranged in a RAID-4 or RAID-5 array, a method of improving the performance and reliability of the array in the absence of a member. The method re-organizes the array into the equivalent of a higher performance and reliability RAID-0 organization while allowing concurrent high performance application access to the array and includes a deliberate reorganization activity concurrent with application access. The method also restores the RAID-4 or RAID-5 organization subsequent to the failure of a member using a replacement member while continuing to allow concurrent high performance application access to the array. In order to perform this reorganization on-line state information is maintained for each parity block, each data block and the array itself. A recently removed disk may be reinserted using an expedited replacement process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.