Patent ID: 8225039
Filing Date: 2012-07-17
Classification: G06F

Abstract:
1. A storage system, comprising: a virtual volume; a plurality of RAID groups including either one or a plurality of storage devices; a pool unit for managing a plurality of first real storage areas, which are respectively disposed in a stripe shape in each of the RAID groups, and the first real storage areas have a plurality of second real storage areas respectively; a controller, which, in a case where a write command related to the virtual volume is issued from a higher-level device, selects a prescribed second real storage area from among the respective second real storage areas included in a prescribed first real storage area of the respective first real storage areas, and associates this prescribed second real storage area with a prescribed area inside the virtual volume corresponding to the write command, and which associates one virtual volume with one first real storage area; a migration destination determination unit, which selects a migration-targeted second real storage area from among the respective second real storage areas associated with the virtual volume, and selects a migration-destination first real storage area, which is to become the migration destination of data stored in the migration-targeted second real storage area, from among the respective first real storage areas inside another RAID group other than the RAID group in which the migration-targeted second real storage area of the respective first real storage areas is disposed; a migration-destination storage unit which associates the migration-targeted second real storage area with the migration-destination first real storage area, and stores the migration-targeted second real storage area associated with the migration-destination first real storage area; and a command processor, which, in a case where the higher-level device has issued a command corresponding to the migration-targeted second real storage area, migrates, during command processing, the data stored in the migration-targeted second real storage area to the migration-destination first real storage area stored by the migration-destination storage unit.