Patent ID: 7418530

Claim:
A storage device, comprising: an upper level interface control unit that controls data exchanges with a host device; a lower level interface control unit that controls data exchanges with a memory drive; and a memory unit that is shared by the upper level interface control unit and the lower level interface control unit, a packet size management information storage unit that stores first packet size management information for which a first packet size is preset for each of a plurality of types of communication protocols and communication bandwidths that can be used in exchanges with the host device, wherein the upper level interface control unit judges the type of communication protocol that is used in exchanges with the host device and, by referencing the first packet size management information, reads and sets the first packet size suited to the communication protocol type thus judged, such that the upper level interface control unit variably sets the first packet size that is used in exchanges with the memory unit on the basis of the type of communication protocol and the communication bandwidth that is used in exchanges of the upper level interface control unit with the host device.