The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 14, 2015
Filed:
Apr. 04, 2013
Hitachi, Ltd., Tokyo, JP;
Akiyoshi Tsuchiya, Tokyo, JP;
Jun Nemoto, Tokyo, JP;
Hitoshi Kamei, Tokyo, JP;
Masakuni Agetsuma, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Regarding a method for migrating a file system by copying a file from a migration source to a migration destination and deleting the file at the migration source, a retention of a file in a page (allocation unit of a thin provisioning function) is either suppressed or solved, and two methods are proposed for solving the problems and for enabling migration of a file system in which the increase of utilization of storage capacity is suppressed, wherein one method changes the location of a file prior to performing copying so that the file to be copied next is located in the same page, and another method creates a reverse index table to recognize which block is used by files, thereby enabling to specify the file remaining within a page and copy the same by referring to this reverse index table.