Technique for decision criterion for determining a transfer destination layer in rearrangement processing. A computer configures rearrangement reference information showing whether an access characteristic related to a task executed on a plurality of host computing devices is considered as a decision criterion for transfer destination determination in rearrangement processing of transferring data between actual storage areas of physical storage devices of different response performance. Storage subsystem refers to the rearrangement reference information and, based on an access characteristic of the plurality of computing devices with respect to the actual storage areas assigned to the plurality of computing devices, executes rearrangement processing of transferring data stored in the actual storage areas to different actual storage areas in the physical storage devices of different response performance.