A system includes: a first input buffer that functions as an input buffer for a third storing area; and a second input buffer that functions as an input buffer for the third storing area and that separately stores data with a high update frequency for the third storing area. In the system, a plurality of data written in a first storing area or a second storing area are flushed to the first input buffer in units of logical blocks. Also, a plurality of data written in the first input buffer are relocated to the third storing area in units of logical blocks.