Fault tolerant disk drive matrix

Patent 5303244 Issued on April 12, 1994. Estimated Expiration Date:

April 12, 2011. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventor

Watson, M. Cameron

Assignee

Application

No. 662744 filed on 03/01/1991

US Classes:

714/5, Of memory or peripheral subsystem365/200Bad bit

Examiners

Primary: Beausoliel, Robert W. Jr.
Assistant: Chung, Phung M.

Attorney, Agent or Firm

Merchant, Gould, Smith Edell, Welter & Schmidt

Foreign Patent References

0249091 EP. 10/13/1987
0369707 EP. 05/13/1990

International Class

G06F 011/00

Abstract

A fault tolerant disk drive matrix comprises a plurality of disk drives. A mapping method associates a subset of the disk drives with a logical RAID-5 array. Each of the disk drives in the matrix may be associated with a plurality of different logical RAID-5 arrays. Logical units of data are subdivided into blocks and stored in an interleaved manner across the disk drives of the logical RAID-5 array. The arrangement of data and parity blocks on the logical RAID-5 arrays within the matrix reduces throughput degradation when a disk drive fails. In the event of a disk drive failure, data blocks stored on the failed disk drive can be reconstructed using redundancy blocks and data blocks from the surviving disk drives within the logical RAID-5 array. Replacement disk drives may also be provided to substitute for the failed disk drive in the logical RAID-5 array. Thus, the mapping of logical RAID-5 arrays to physical disk drives in the matrix may change in position and identity due to disk drive replacements caused by failures.