Disk array having hot spare resources and methods for using hot spare resources to store user data

摘要

A disk array data storage system has a plurality of storage disks (12) and a disk array controller (14) for coordinating transfer of user data to and from the storage disks (12). A memory manager (16) is provided to manage memory allocation and data storage on the disk array (11). The memory manager maintains a sufficient quantity of hot spare storage space that can be made available for reconstructing the user data and restoring redundancy in the event one of the storage disks fails. Until a disk fails, however, the memory manager (16) uses the hot spare space to store user and redundant data while guaranteeing that the storage space can be used for rebuilding following a storage disk failure. In this manner, all storage disks (12) in the array are used to store user data, and additionally to maintain storage space that can be easily made available for purposes of hot spare in the event of disk failure.