Patent ID: 8171215
Filing Date: 2012-05-01
Classification: G06F,Y02D

Abstract:
1. A file server, communicably coupling to a storage device having plural RAID groups, each including at least one volume and communicably coupling to a client that makes a file access request to files, and managing files stored on the RAID groups, using real file systems created to the RAID groups and virtual file systems created by virtually integrating the real file systems, comprising: a memory device having memory area for creating information to be stored on the storage device; and a controller, wherein the storage device storing: mapping information that associates a file name used for managing the files in the virtual file systems, the RAID groups on which the files are stored, and the real file systems that actually manages the files, with one another for each of the files; and schedule information in which, for each of the RAID groups, a stop time period to spin down and stop the RAID group, and an operation time period to spin up and operate the RAID group are defined, wherein the controller acquires the file name and a file access date/time included in a file access request in response to the file access request made by the client, and creates access information that associates the file name with the file access date/time, and stores the created information on the storage device, wherein the controller classifies files by grouping files having a common file access time period into one group based on the access information, defines some of the RAID groups on which the files grouped into said one group is to be stored in such a manner that the file access time period and the stop time period are not overlapped, migrates the files of said one group to the defined RAID groups during being operated, and updates the mapping information regarding the migrated files, and wherein the controller executes a spin down operation for the RAID groups in the stop time period, and executes a spin up operation for the RAID groups in the operation time period.