This invention provides a system including a computer and a storage-subsystem comprising at least either a first storage area for storing data sent from the computer or a second storage area to be associated with the first storage area, for storing replicated data of data stored in the first storage area. This system includes a replication processing status referral unit for referring to a replication processing status of data of the first storage area and the second storage area to be associated, and an output unit for outputting first performance information concerning data I/O stored in the first storage area, and outputting second performance information concerning data I/O stored in the second storage area together with the first performance information when the replicated data is being subject to replication processing from the first storage area to the second storage area as a result of referring to the replication processing status.