| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve performance under the consideration of access frequency in data migration. Ž<P>SOLUTION: In a controller 16 of a tape drive, if a command processing part 61 receives a data read instruction, a channel input/output part 63 reads data from a tape, Ram-count showing the number of times that the tape is mounted for reading is stored in each data on the tape, and Dm-readfreq showing the history of the number of data reads is stored in the read data. In data migration, a CM input/output part 64 reads the Ram-count and Dm-readfreq, a frequency calculation part 65 calculates the ratio of the number of times shown by Dm-readfreq to the Ram-count as access frequency, and a migration control part 66 controls a buffer management part 62 or the like so that the data read from the migration source tape can be recorded in the order of access frequency into the migration destination tape. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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