Hitachi, Ltd.

Ken-ichi Takamoto

Minoru Yoshida

Naoya Takahashi

Kazuo Nakagoshi

Makoto Kogai

The write data is entered from the upper unit into a nonvolatile cache provided in a controller inside of each disk unit through a channel adaptor, a cache shared by each disk, and a disk adaptor. The data from the cache is compressed by the data compressing and restoring device and is written in the disk. At a time, the management information for compressed data is written in the cache and the disk as well. In case of breaking the management information of the cache when a failure takes place in the cache memory, the management information is written for each disk. Hence, the breakage does not have an adverse effect on the other disks. If the management information of the cache is broken, the management information given into the disk may be replaced with the broken information.

Growing community of inventors

Odawara, Japan

Ken-ichi Takamoto