STORAGE SYSTEM

PROBLEM TO BE SOLVED: To solve the problem that the transfer of video files from a secondary storage to a primary storage is necessary in a hierarchical file management device, and that the transfer of video files with high picture quality and large capacity especially takes time.SOLUTION: On the basis of program information acquired from a management server for holding program information (program name, broadcasting time, genre and tag information), the transfer of video files which are likely to be used from a secondary storage to a primary storage is controlled. It is not necessary to delete the video files from the primary storage during a designated holding period. Also, the holding of the primary storage is ended in a timing after the lapse of a period in which the video files are likely to be used, and the video files on the primary storage may be treated as cache.