| 摘要 |
PROBLEM TO BE SOLVED: To easily realize the capacity efficiency improvement of a secondary storage device. SOLUTION: This device is provided with an address conversion map 111 assigning at least one logical lock to the logic block of a disk device 12 and assigning a pointer to a physical block with a logic block image at the time point of the newest checking point and a pointer to a physical block with a newest block image to each block, and an ineffective block managing module 113 managing a physical block without effective data on the disk device. Then, in a check point processing, the physical block with the newest logic block image in each logic block on the conversion map is set to be a physical block with a check point image with respect to the logical block and a newest image, and the physical block with the logic block image at the time point of a checking point in each logic block on the conversion map at the time of recovery is set to be a physical block with a check point image with respect to the logic block and the newest image. |
