Patent ID: 7404035

Claim:
A system for storing data of a file system comprising: a controller controlling the file system; and a disk array system storing data of the file system, wherein the disk array system includes a plurality of logical volumes, each of which is configured by using a disk device, and a disk controller controlling data input/output to/from the plurality of logical volumes, wherein the plurality of logical volumes includes at least one first type logical volume configured by a disk device, which is controlled to spin down or up according to a last access time to the first type logical volume, and at least one second type logical volume configured by a disk device, which is controlled not to spin down according to a last access time to the second type logical volume, wherein the controller is configured to store data satisfying a predetermined condition in the second type logical volume, wherein the controller is configured to store data, whose access frequency is higher than a predetermined criterion in the second type logical volume, wherein the controller is configured to store metadata of the file system in the second type logical volume, wherein the controller includes a metadata cache unit for storing metadata of the file system, and when an access request for a file of the file system is received, the controller is configured to check whether metadata used to confirm a storage location of the file is stored in the metadata cache unit or not, if the metadata is stored in the metadata cache unit, the controller is configured to specify a logical volume of the disk array system, in which the file is stored, by using the metadata in the metadata cache unit, if the metadata is not stored in the metadata cache unit, the controller is configured to specify a logical volume of the disk array system, in which the file is stored, by using the metadata in a logical volume of the disk array system, and the controller is configured to issue an access request for a specified logical volume to access data of the file.