Data are stored using a writing method according to the property of the data in a storage device. An area defining unit defines, in a second memory, a system area for storing system information causing a system to operate and a cache area temporarily storing data of a first memory. A moving processing unit moves data stored in the cache area to the first memory at a predetermined point in time. An access control unit accesses the second memory in accordance with the definition with regard to access corresponding to the system area or the cache area, and read data from the first memory with regard to read-access corresponding to those other than the system area and the cache area.