A non-transitory computer-readable recording medium having stored therein a program for controlling storage, the program instructing a computer including a storing device to execute a process comprising:
- generating data access prediction information in relation to the storing device based on a data access history to a unit region of the storing device;
- comparing first concentration state tendency information and second concentration state tendency information, the first concentration state tendency information being collected during a first time period and indicating a tendency of a concentration state of a unit region being in the concentration state on which unit region data accesses are concentrating in the storage device, the second concentration state tendency information being collected during a second time period prior to the first time period and indicating a tendency of the concentration state of the unit region in the concentration state,
- in a case where the first concentration state tendency information is detected to vary by a standard value or more from the second concentration state tendency information as a result of the comparing, regenerating the data access prediction information by excluding a data access history collected during the second time period, and
- collecting concentration state tendency information indicating a tendency of the concentration state in a unit region being in the concentration state on which unit region data accesses are concentrating at regular intervals of a predetermined time period based on a data access log of each of the plurality of unit regions of the storing device,
- the comparing compares the first concentration state tendency information collected during the first time period from a time of starting determination to a first timing, the first timing being before the predetermined time period from the time of starting determination and the second concentration state tendency information collected during the second time period from the first timing to a second timing which is before the predetermined time period from the first timing, and
- the storing device comprises a first storing device and a second storing device having a different performance from that of the first storing device, the first storing device and the second storing device serving as the storing device;
- and
- the process further comprises:
- specifying a unit region storing data to be migrated between the first storing device and the second storing device based on the data access prediction information;
- issuing an instruction to migrate data in the unit region specified by the specifier between the first storing device and the second storing device,
- the data access prediction information is configured to associate each of a plurality of times having elapsed since the occurrence of the concentration state with a predicted value representing a remaining duration time of the concentration state,
- predicting the remaining duration time of the concentration state by referring to the data access prediction information based on time elapsed since access concentration was detected,
- calculating speed of movement of the access concentration based on occurrence position of the access concentration and the time of the access concentration,
- obtaining predicted access concentration region based on the remaining duration time of the concentration state and speed of movement of the access concentration, and
- specifying the predicted access concentration region as the unit region to be migrated.