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:
Sep. 09, 2014
Filed:
Nov. 25, 2011
Masayoshi Ohara, Odawara, JP;
Koji Nagata, Kaisei, JP;
Kosuke Sakai, Isehara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A controller for the storage apparatus: creates a second logical volume in a storage area provided by one or more storage devices; stores management information of a snapshot of a first logical volume, which is to be provided to a host computer, in the second logical volume; and reads the management information of a necessary snapshot from the second logical volume to a memory when needed, executes processing using the read management information, and returns the management information, which becomes no longer necessary, from the memory to the second logical volume. When reading the management information of the necessary snapshot from the second logical volume to the memory when needed, the controller changes the number of generations and address range of the snapshot of the management information to be read to the memory according to a generation and address of the snapshot whose management information is required.