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:
Dec. 16, 2008
Filed:
Aug. 03, 2006
Yoshifumi Zimoto, Odawara, JP;
Ikuya Yagisawa, Machida, JP;
Atsushi Ishikawa, Minamiashigara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
Proposed is a storage apparatus and its control method capable of performing dynamic load balancing or performance acceleration as a whole by balancing the load to a logical volume. With this storage apparatus, the load status of the volume is measured based on the data volume and command throughput transferred between the higher-level device and the storage unit. In addition, the contents of the volume having a load exceeding the default value are copied to one or more backup volumes based on the measurement results of the load status of the volume, the volume of a copy source and the backup volume of a copy destination are associated with one virtual volume, and the virtual volume is provided to the higher-level device. Moreover, when a write request involving read processing for reading data from the virtual volume is given from the higher-level device, data is read from a default volume or the backup volume associated with the virtual volume and data from the higher-level device is written in all the volumes and backup volumes associated with the virtual volume, and, when a read request for reading data from the virtual volume is given, corresponding data is read from the volume or the backup volume other than the default volume or backup volume among the volume and the backup volume associated with the virtual volume.