Patent ID: 8560879

Claim:
A method of efficiently recovering lost data in a data storage system, comprising: determining a logical address associated with lost data of a failed memory device of a first data storage device of the data storage system; analyzing the logical address to determine how copied data corresponding to the lost data are arranged in the data storage system, the analyzing comprising analyzing whether copied data blocks associated with the logical address are scattered over non-contiguous physical address regions of a second data storage device of the data storage system; and based on how the copied data are arranged in the data storage system, selectively recovering a first portion of the lost data by reading at least some of the copied data from the second data storage device and selectively recovering a second portion of the lost data from parity information in the first data storage device, wherein the selectively recovering a second portion comprises responsive to the second portion of the lost data being stored within non-contiguous physical address regions of the second data storage device, recovering the second portion of the lost data from the parity information in the first data storage device.