Nonvolatile Semiconductor Memory Drive, Information Processing Apparatus and Management Method of Storage Area in Nonvolatile Semiconductor Memory Drive

An information processing apparatus comprising:

• a main body device;
• and
• a nonvolatile semiconductor memory drive comprising a nonvolatile semiconductor memory,
• the main body device comprising a data access request module configured to issue a data access request for the nonvolatile semiconductor memory to the nonvolatile semiconductor memory drive,
• the nonvolatile semiconductor memory drive further comprising a controller configured to control a process of writing and reading data with respect to the nonvolatile semiconductor memory,
• the controller of the nonvolatile semiconductor memory drive comprising:
• a compaction control module configured to acquire free groups set in an unused state by rearranging valid data scattered in n groups in groups of a number not larger than n-1 when the number of free groups remaining in a plurality of groups formed as a storage area management unit of the nonvolatile semiconductor memory becomes not larger than a predetermined number;
• a compression control module configured to acquire free groups by compressing stored data in m groups in which access to stored valid data has not been made for a period longer than a predetermined period and rearranging the compressed data in groups of a number not larger than m-1;
• and
• a control module configured to interrupt one of the rearrangement processes by the compaction control module and compression control module when a data access request for the nonvolatile semiconductor memory is issued from the main body device while one of the rearrangement processes by the compaction control module and the compression control module is being performed.