Patent ID: 7219092
Filing Date: 2007-05-15
Classification: G06F,Y10S

Abstract:
1. A computer system for detachable storage, comprising: a computer; a connected storage device connected to said computer; means for registering identification information about an unnecessary file to identify one or more unnecessary files; first means for determining whether a file stored on said connected storage device is one of said unnecessary files; second means for determining whether said file is to be migrated to another storage device; an unnecessary file table having information between each of a plurality of migration source storage devices and none or at least one file corresponding to one of the migration source storage devices and not to be migrated to any one of a plurality of migration destination storage devices, wherein the unnecessary file table registers therein, for each file, a file name a related directory name an update time and a storage device name of the migration source storage device which stores said each file, and registers files requiring no data migration, wherein an unnecessary file does not need to be migrated to any one of said data migration destination storage devices; means for allowing the user to setup, through an input device, conditions of unnecessary files to be registered in the unnecessary file table, and searching, under the setup conditions, the migration destination storage devices to identify files that meet the conditions and register the identified files in the unnecessary file table, wherein the conditions of the unnecessary files set up by the user include setting a condition that a file be left unaccessed during a certain period of time, so that an unnecessary file table, wherein data migration is not performed for a given file if the given file is registered in the unnecessary file table, and data migration is performed for the given file if the given file is not registered in the unnecessary file table; and said computer checking all files in a first migration source storage device to determine whether each of the files thereof is an unnecessary file or an already migrated file which has been migrated to one of the migration destination storage devices, wherein after checking all the files, the computer starts data migration operation on only the files that are not unnecessary files; wherein the computer detaches the first migration source storage device from the computer system if all the files thereof are unnecessary files or have been migrated after said checking.