| 摘要 |
PROBLEM TO BE SOLVED: To create a copy region with a hard disk capacity smaller than that in the conventional manner and hold it, and to reduce a processing load in creating the copy region. SOLUTION: Data (a) outputted from a host computer 12 side by a prescribed point of time is stored as main data in a hard disk 13 (#1). Data (a) outputted from the host computer 12 side after the prescribed point of time are partitioned by generations as data for every prescribed generation, associated with generation numbers, and stored in hard disks 13 (#2 to #n). Data by generations with the smallest generation number (e.g., data by generations stored in the hard disk 13 (#2)) among the data by generations stored in the hard disks 13 (#2 to #n) is overwritten on the main data to thereby update the main data. The data by generations with the smallest generation number is erased from the hard disk 13 (#2) at the same time. The generation numbers of the respective data by generations stored in the hard disks 13 (#3 to #n) are updated to smaller generations by one generation, respectively. COPYRIGHT: (C)2004,JPO
|
