Memory systems with data storage redundancy management

摘要

A disk array (10) has a plurality of disks (12), a disk array controller (14) for coordinating data transfer to and from the disks, and a RAID management system (16) for mapping two different RAID areas (42,44) onto the disks. The RAID management system (16) stores data in one of the RAID areas according to mirror redundancy, and stores data in the other RAID area according to parity redundancy. The RAID management system (16) then shifts or migrates data between the mirror and parity RAID areas on the disks in accordance with a predefined performance protocol, such as data access recency or access frequency. A method for managing data on a disk array is also disclosed.