System for recovering data stored in failed memory unit
Fault-tolerant memory system
High capacity disk storage system having unusually high fault tolerance level and bandpass
Parity spreading to enhance storage access
Data error correction system
Method of recording in a disk memory and disk memory system
Controlling asynchronously operating peripherals
Memory unit backup using checksum
Parallel drive array storage system Patent #: 4870643
ApplicationNo. 463512 filed on 01/11/1990
US Classes:714/7, Reconfiguration (e.g., adding a replacement storage component)360/902, Storage density (e.g., bpi, tpi)360/903, Physical parameter (e.g., form factor)714/766Check bits stored in separate area of memory
ExaminersPrimary: Atkinson, Charles E.
Attorney, Agent or Firm
International ClassG06F 011/20
AbstractThe disk drive memory of the present invention uses a large plurality of small form factor disk drives to implement an inexpensive, high performance, high reliability disk drive memory that emulates the format and capability of large form factor disk drives. The plurality of disk drives are switchably interconnectable to form parity groups of N+1 parallel connected disk drives to store data thereon. The N+1 disk drives are used to store the N segments of each data word plus a parity segment. In addition, a pool of backup disk drives is maintained to automatically substitute a replacement disk drive for a disk drive in a parity group that fails during operation.