Patent ID: 7877626

Claim:
A method for disk storage device rebuild in a data storage system including disk storage devices grouped in at least one tier parity group, a processor unit operatively coupled to said disk storage devices, a memory structure operatively coupled to said disk storage devices, and a parity engine coupled to said disk storage devices, the method comprising the steps of: operatively coupling a journaling unit and a rebuild unit to said processor unit; detecting a failed condition of at least one disk storage device and identifying said at least one storage device as failed, said at least one disk storage device containing a plurality of data sections residing thereon; taking said at least one storage device identified as failed off-line; activating said journaling unit responsive to said at least one disk storage device being identified as failed, said journal unit performing the steps of: creating a journal structure in said memory structure, storing in said journal structure a configuration of the disk storage devices in said at least one tier parity group, tracking updates applied to said at least one disk storage device subsequent to being identified as failed, said updates being intended for application to respective first data sections thereof, mapping in said journal structure said updates to said respective first data sections; and activating said rebuild unit to rebuild said respective first data sections mapped in said journal structure responsive to said at least one storage device being brought back on-line, said at least one disk storage device having second data sections ignored by said rebuild unit to thereby reduce a time period required to return said at least one storage device to an operational status.