Patent ID: 8234519
Filing Date: 2012-07-31
Classification: G06F

Abstract:
1. A storage system comprising: a first storage device having a first plurality of hard disk drives and a first controller controlling the first plurality of hard disk drives; wherein the first controller stores data in the first plurality of hard disk drives by stripes, the hard disk drives each include a plurality of parcels and the parcels each include a plurality of stripes, each stripe includes M data and N parity data, where M and N are integers, and the first controller calculates for each stripe the N parity data using the M data, wherein the M data and N parity data of the each stripe are allocated to M+N hard disk drives of the first plurality of hard disk drives, wherein a first hard disk drive of the first plurality of hard disk drives includes data or parity data of both a first stripe of the stripes and a second stripe of the stripes, while a second hard disk drive of the first plurality of hard disk drives includes data or parity data of only one of the first stripe of the stripes or the second stripe of the stripes, wherein during data recovery involving failure of one of the first plurality of hard disk drives as a failed hard disk drive, the first controller makes an allocation area based on the parcel, and copies data from the failed hard disk drive to the allocation area.