Patent ID: 8850152

Claim:
A method of data migration from a source volume including storage areas of a plurality of source storage tiers different in performance capability to a destination volume including storage areas of a plurality of destination storage tiers different in performance capability, data relocation being performed among the plurality of source storage tiers in accordance with accesses to the source volume during the data migration, the method comprising: starting the data migration between volumes from the source volume to the destination volume; acquiring information on a data arrangement in the source volume determined based on an access history to the source volume during the data migration between volumes from the source volume to the destination volume; determining a data arrangement in the destination volume during the data migration between volumes based on the data arrangement indicated by the acquired information; creating a schedule of the data migration between volumes from the source volume to the destination volume before starting the data migration between volumes from the source volume to the destination volume, the schedule indicating destination storage tiers of data which is in the source volume and has not migrated to the destination volume; performing the data migration between volumes from the source volume to the destination volume in accordance with the schedule; and updating the destination storage tiers in the schedule based on the acquired information.