Patent ID: 7469315
Filing Date: 2008-12-23
Classification: G06F,Y02D

Abstract:
1. A storage controller which is connected to at least one host device and a plurality of storage devices, the storage controller comprising: a plurality of physical storage devices, each of which is configured from storage regions of a predetermined number of storage devices among the plurality of storage devices; at least one logical storage device which can be set in the storage region of each of the physical storage devices; an access information collection portion which collects access information about each of the physical storage devices and each of the logical storage devices on the basis of the status of access from the host device to each of the logical storage devices; a power supply mode setting portion which sets a power supply mode for supplying power for each of the physical storage devices on the basis of the access information about each of the physical storage devices; a power control portion which controls supply of power to each of the storage devices configuring each of the physical storage devices, on the basis of the set power supply mode; a relocation plan creation portion which creates a relocation plan for moving each of the logical storage devices between the physical storage devices having different power supply modes, on the basis of the access information about each of the logical storage devices; an execution time determination portion which sets an execution time for executing the created relocation plan; and a relocation execution portion which moves a logical storage device, which is judged as a target of relocation from among the logical storage devices, from a source physical storage device to a destination physical storage device, on the basis of the created relocation plan, when the determined execution time comes, wherein (1) the power supply mode setting portion calculates an access frequency to each of the physical storage devices on the basis of the access information about each of the physical storage devices, (1-1) sets a long-time energization mode in which a power supply time period is relatively long, for each of the storage devices configuring the physical storage device in which the calculated access frequency is relatively high, and (1-2) sets a short-time energization mode in which a power supply time period is relatively short, for each of the storage devices configuring the physical storage device in which the calculated access frequency is relatively low, (2) the relocation plan creation portion calculates an access frequency to each of the logical storage devices on the basis of the access information about each of the logical storage devices, to create a relocation plan by: (2-1) selecting a physical storage device, which is set to the long-time energization mode, as a destination of the logical storage device in which the calculated access frequency is relatively high; and (2-2) selecting a physical storage device, which is set to the short-time energization mode, as a destination of the logical storage device in which the calculated access frequency is relatively low.