Patent ID: 7676610

Claim:
A data input/output device which controls input/output of data to and from a host processing device as a host device, comprising: a host status information storage unit holding host status information including priorities of host device processes which are performed or are to be performed in the host device; an input/output notification unit notifying the host device of data input/output control by a notification including either an interrupt notification process of performing an interrupt in the host device or a non-interrupt notification process of not performing the interrupt; a host status information acquisition unit acquiring the host status information from the host device, the host status information indicating a status of one or more of the host device processes performed in the host device by each of “Run”, “Ready”, or “Wait” status and indicating a priority of each host device process which is performed or is to be performed in the host device, and storing the host status information in the host status information storage unit; and an optimization unit designating a target host device process from among the host device processes in the host device, for handling data in the data input/output control, and selecting one of the interrupt notification process or the non-interrupt notification process according to a status and priority of the target host device process, wherein the input/output notification unit notifies the host device of the data input/output by the notification selected by the optimization unit according to the status and the priority of the target host device process.