Hitachi, Ltd.

Hitachi Vantara Corporation

Jun Miyashita

Tomohiro Yoshihara

Shinichi Hiramatsu

Sadahiro Sugimoto

Takashi Ochi

Naoya Okada

Takashi Nagao

Masaru Tsukada

Masahiro Tsuruya

Hidetoshi Sakaki

Junichi Muto

Toshiya Seki

Kazue Jindo

Akihiro Shikano

Yuya Goto

Erina Nogi

A storage device includes a processor and an accelerator configured to compress and decompress data. The processor receives first replacement write data for a part of a first logical address region to update first data in the first logical address region that has been compressed by basic compression unit. The processor instructs the accelerator to compress the first replacement write data by a size smaller than the basic compression unit. The accelerator compresses the first replacement write data by the smaller size. The processor merges not-to-be-replaced data in the first logical address region and the first replacement data that are decompressed by the accelerator to generate uncompressed data having a size of the basic compression unit. The processor instructs the accelerator to compress the uncompressed data by the basic compression unit.

Storage device

The storage system includes a controller and a storage drive accessible from the controller. The controller includes a memory and a processing unit. The memory includes a first cache area in which the writing of data by the storage drive is permitted, and a second cache area in which the writing of data by the storage drive is prohibited. A In the first cache area, the storage of data, by staging-in-advance in response to a read request for a sequential read, by the processing unit is permitted, and the storage of cache data in a dirty state by the processing unit is prohibited. In the second cache area, the storage of the cache data in the dirty state by the processing unit is permitted.

Storage system

Each node constituting a distributed storage system includes one or more controllers. Each controller includes an actual queue group for each drive physically coupled to the controller, and a virtual queue group for each of a plurality of drives. A Drive-IO issued by any controller and received is accumulated in the actual queue group corresponding to an issue destination drive of the Drive-IO after accumulated in the virtual queue group corresponding to the issue destination drive.

Distributed storage system

The present invention continues host access and holds data of a migration source volume as the latest data even when a fault occurs in any of a plurality of access paths. Upon receiving a first write command from a host computer via a first access path, the migration source controller writes first update data to the migration source volume and, upon receiving a second write command from the host computer via a second access path, the migration destination controller transfers second update data to the migration source controller via a storage path and, upon receiving the second update data from the migration destination controller, the migration source controller writes the second update data to the migration source volume.

Computer system and data migration method

A storage apparatusincludes a communication control processorthat is a processor configured to control communications with a host apparatus, and plurality of main processorseach configured to perform an I/O process on a storage driveaccording to an I/O request received from the host apparatus. The storage apparatusmanages data to be stored or that has been stored in the storage drivein accordance with the CKD format. The storage apparatusdistributes the I/O process to the plurality of main processorsin units of the data fields on basis of the operation rates of the respective main processors, information on a C field, a K field, and a D field that are data fields forming a record of data targeted by the I/O process and managed in CKD format, and an I/O load indicator being a load indicator of the I/O process currently running on each of the main processors.

Storage apparatus and method of controlling the same

Growing community of inventors

Tokyo, Japan

Jun Miyashita