摘要 |
A method and system for differential backup of a logical disk of a data storage array is presented. The system comprises: a pool of physical storage space divided into a plurality of addressable memory locations; and a logical disk adapted to store metadata associated with a differential snapshot of the logical disk. The metadata comprises a mapping structure defining a sharing relationship between the differential snapshot of the logical disk and a previous snapshot of the logical disk that is arranged to serve as a baseline snapshot of the logical disk. The mapping structure is adapted to indicate disk regions of the logical disk that have changed in the differential snapshot of the logical disk with reference to the baseline snapshot of the logical disk. |