STORAGE DEVICE, ALLOCATION RELEASE CONTROL METHOD, AND ALLOCATION RELEASE CONTROL PROGRAM

摘要

PROBLEM TO BE SOLVED: To efficiently release a physical disk area allocated to a logical area that requires no allocation of a physical disk area.SOLUTION: A releasing unit 221 skips checking a fixed number of chunks when a predetermined number of chunks that are not all zero continue. The releasing unit 221 identifies a position of meta data on the basis of an OS and a file system and does not check chunks including the meta data. The releasing unit 221 checks chunks continuing on a physical disk area.