Patent ID: 8650358
Filing Date: 2014-02-11
Classification: G06F,Y02D

Abstract:
1. A storage system that is coupled to at least one host, comprising: a plurality of Redundant Array of Independent Disks (RAID) groups; and a controller that is coupled to the plurality of RAID groups and the at least one host, wherein each of the plurality of RAID groups is configured by at least two physical storage devices, the plurality of RAID groups is a basis of a pool that is a storage area that is configured by a plurality of real areas, the controller provides a plurality of virtual volumes that are associated with the pool to the at least one host, each of the virtual volumes is a virtual logical volume that is configured by a plurality of virtual areas, and in the case in which the controller receives a write command from the at least one host, the controller specifies a virtual area of a write destination from the write command, allocates a free real area of the pool to the specified virtual area of the write destination, and writes write target data accompanying the write command to the allocated free real area, (A) wherein in performing an electrical power saving processing, the controller specifies a first virtual volume (VVOL) that is a virtual volume of an electrical power saving target, (B) the controller specifies a first RAID group (RG) that is a RAID group of the electrical power saving target, (C) the controller judges whether or not there is a first real area that is allocated to a second VVOL that is a virtual volume other than the first VVOL and that is a real area based on the first RG, (D) in the case in which the result of the judgment in (C) is positive, the controller moves data in the first real area to a free real area based on a second RG that is a RAID group other than the first RG, and executes a first moving processing in which a real area based on the second RG, is allocated, as a substitute for the first real area to a virtual area to which the first real area is allocated, and (E) the controller sets all physical storage devices that configure the first RG to be in an electrical power saving state in the case in which there is no real area based on the first RG that is allocated to the second VVOL; and wherein the controller selects the first RG from the plurality of RAID groups based on a capacity of the selected first RG being smaller than a capacity of other RGs of the plurality of RAID groups.