An SDS node adjusts a physical capacity included in a logical volume provided to a tenant and is to be allocated to the tenant, based on the size of data written from the tenant. An operation management system provides storage to the tenant and adjusts the provided storage to include a node and a capacity allocation and recovery system. The node provides the logical volume of the storage to the tenant, receives writing of data to the logical volume from the tenant, and writes the received data to a region included in the storage and having the physical capacity allocated to the tenant. The capacity allocation and recovery system determines a physical capacity to be interchanged based on the size of the logical volume, the size of the written data, and the physical capacity allocated to the tenant, and notifies information on the determined physical capacity to the node.