Patent ID: 6915379

Claim:
A storage subsystem comprising a plurality of storage devices connected to a host computer, wherein a first storage device included in said plurality of storage devices comprises: means for receiving a request for information processing for said storage subsystem, said information processing being executed in said host computer; means for transferring the received request to a second storage device included in said plurality of storage devices; and means for executing information processing indicated by the received request when the received request should be executed by said first storage device based on cooperation control information which indicates a the request to be executed by the first storage device, wherein each of the plurality of storage devices control RAID level cooperatively, said second storage device comprises: means for receiving the transferred request; and means for executing information processing indicated by the transferred request when the transferred request should be executed by said second storage device based on the cooperation control information which indicates a request to be executed by said second storage wherein the first and second storage device control RAID level 4 or 5, wherein, if the request is a data write request, the first storage device receives data connection with the data write request, stores the data, makes another data to be used for making parity data in the second storage device and sends the another data to the second storage device, wherein the second storage device receives the another data, makes parity data based on the another data, and stores the parity data, wherein in said first storage device, said means for transferring a request adds information, which indicates said first storage device, to the request to be transferred, and wherein said second storage device further comprises means for suppressing another transfer of the transferred request based on the added information that indicates said first storage device.