US Patent 8006040 Data storage device and method thereof

A microprocessor 18 in a control device 13 of a data storage device determines that the read request has a sequential access property, when a transfer size of data specified by a read request from a host computer 11 is the same as a preset pre-fetch determination size and sends the data for the read request to the host computer 11. The microprocessor 18 also reads data in succeeding areas continuous to the data designated by the read request from a storage device 12 into a cache memory 20. The data storage device enables to reduce a number of access from the control device 13 to the storage device 12, improving a response time as well as throughput of the data storage device.