A plurality of storage devices connected to at least one host computer via a network is to be managed. Access information about accesses from the host computer to each of the storage devices is referred to; a storage area in the storage device that has low access efficiency is determined based on the access information; a host computer having low access efficiency in view of the storage area having low access efficiency is determined based on the access information; a storage area having high access efficiency at least from the host computer having low access efficiency is determined; and data that is stored in the storage area having low access efficiency and used by the host computer having low access efficiency is transferred to the storage area having high access efficiency.