公开(公告)号：WO1992009952A1

公开(公告)日：1992-06-11

申请号：PCT/US1991007643

申请日：1991-10-18

Applicant: STORAGE TECHNOLOGY CORPORATION

Inventor： STORAGE TECHNOLOGY CORPORATION ,  CRATER, Michael, Richard ,  HALDEMAN, David, Paul

IPC: G06F11/08

CPC classification number: G06F11/1076 ,  G06F11/1008 ,  G11B20/18 ,  G11B20/1833

Abstract: The data storage subsystem (100) of the present invention uses a large plurality of small form factor disk drives (122-* to 125-*) to implement an inexpensive, high performance, high reliability disk drive memory that emulates the format and capability of large form factor disk drives. The data transmitted by the associated computer system (11) is used to generate redundancy information which is written with the data across N+M disk drives (122-*) in a redundancy group (122) in the data storage subsystem (100). To clear the redundancy accumulator memory (301), an associated pointer memory (302) is used to indicate the ones of the redundancy accumulator memory (301) byte positions that were used in the previous redundancy calculation. As data is received from the computer system (11), the pointer memory (302) is checked to determine whether this next byte position need be reset to erase the previously stored redundancy calculation residue. If not, the data is simply stored therein.