Fujitsu Corporation

Shinya Mochizuki

Kazuhiko Ikeuchi

Mikio Ito

Hideo Takahashi

Norihide Kubota

Yoshihito Konta

Tsukasa Makino

Hiroaki Ochi

Yasutake Sato

Hidejirou Daikokuya

Hidejiro Daikokuya

Yasutake Satou

Koji Uchida

Akihito Kobayashi

Shinichi Nishizono

Katsuhiko Nagashima

Hideki Yamanaka

In a system for dispersively storing data and parity in a plurality of storage devices, information in a first storage device is restored by using information stored in the storage devices other than the first storage device when the first storage device fails. And information in a non-restored area in the first storage device and information in a second storage device are restored by using information stored in the storage devices other than the first and the second storage devices when the second storage device fails while the information in the first storage device is being restored.

Storage control apparatus and method

A system creates a configuration definition table to be used for accessing a physical disk according to a host I/O request, to decrease a memory size of the configuration definition table even if common firmware is used for models with different scales. For this, a model correspondence table to show the definition of each model is provided in a configuration setup processing module, the maximum values of this model are recorded in a memory based on this content, and a memory area for each item is secured. And the actual content of the configuration definition is developed on the secured memory. Therefore even for a diversity of models, the memory size of the configuration definition table can be decreased to a size matching the model, with common firmware regardless the model.

Configuration definition setup method for disk array apparatus, and disk array apparatus

A RAID system access a physical disk according to a host I/O request, and perform Rebuild/Copy back processing, for implementing high-speed Rebuild/Copy back processing without interrupting the processing of a normal I/O. When one disk device out of a plurality of disk devices constituting the RAID configuration fails, the processing size for one time of Rebuild/Copy back to reconstruct the RAID is changed according to the presence of a normal I/O managed in RAID control. When a normal I/O is present, Rebuild/Copy back can be executed without interrupting the processing of the normal I/O, and in a static state where a normal I/O is absent, a processing size larger than the size in that state can be specified so as to implement Rebuild/Copy back processing at high-speed.

RAID system and Rebuild/Copy back processing method thereof

A method and apparatus for enhancing performance of parity check in computer readable media is provided. For example, in a RAID (N+1) configuration, a virtual data strip is added for a calculation of parity. Data of the virtual data strip is set so that a predetermined portion of a data area in the virtual data strip has a predetermined value. Consequently, performance of parity check performed in a data processing system having a RAID configuration can be enhanced.

Method and apparatus for storing a data to memory devices

A RAID system access a physical disk and perform Rebuild/Copy back processing according to a host I/O request, so as to implement high-speed Rebuild/Copy back processing without interfering with the processing of a normal I/O. When one disk device fails, out of a plurality of disk devices constituting a RAID configuration, the controller performs Rebuild/Copy back processing to reconstruct the RAID. In Rebuild/Copy back, the controller reads the data from one disk and writes the data to another disk, so the presence of a normal I/O is judged, and when a normal I/O is absent, read and write of these different disk drives are executed simultaneously. By this, the Rebuild/Copy back time can be decreased.

RAID system, RAID controller and rebuilt/copy back processing method thereof

In the present invention, for each set of blocks [#(0) to #(N&#x2212;1)] storing update data, a history block [#(N)] storing an update state value, for example, a generation, time or check code, showing an update state is provided, constituting a set of management data as a check object. When writing update data on a disk, a new update state value is calculated for the same set of management data and stored in memory as update state confirmation value. The new update state value is also set as write data in the history block in the same set of management data, and the entire of the set of management data including update data and update state value are written onto a disk. The history block is read and disk write omissions are detected by comparing the update state value and the update state confirmation value stored in memory.

Apparatus and method for detecting disk write omissions

A magnetic disk apparatus capable of effectively achieving speedup of the response to a read request, a control method and control program therefore are provided. In a control of a magnetic disk apparatus having a RAID configuration in which the same data is written on two disks, a given algorithm is selected from a plurality of different algorithms with respect to the data stored in the disks, read commands are issued to the data stored in the two disks, respectively, according to the selected algorithm and the data that has been read first by the read commands that has been issued to the two disks in a read command issuance step is adopted as read data.

Magnetic disk apparatus, control method and control program therefor

A storage system has a plurality of disk storage devices and a controller for controlling the plurality of disk storage devices, and diagnosis of a write miss to a disk of the disk storage device. The controller for controlling the plurality of disk storage devices attaches an ID to write data, and after write access to the disk drive, the controller reads the write data from the disk drive, and compares the ID of the read data and the attached ID. The controller updates the ID for each write command. Therefore the old write data and the new write data can be identified, accurate diagnosis is possible, and the failure of an individual disk drive can be detected immediately.

Data storage system, data storage control device, and write error diagnosis method for disks thereof

Storage destination controller devices wherein N number of data strips and M number of parity strips comprised in each stripe are determined so that the parity strips are not continuously stored to the same memory device between two consecutive stripes when a plurality of stripes, each comprising the N number of data strips and the M number of parity strips of different types, are distributed and stored to the N+M number of memory devices.

Storage controller and method for storage control with non-contiguous stored parities

When a write-back request for writing back new data in a cache memory to disk devices forming a redundant configuration of RAID is generated, a write-back processing unit, reserves a parity buffer area in the cache memory, generates new parity, and then, writes the new data and the new parity to the corresponding disk devices. When an error in which the consistency of RAID is broken occurs in a plurality of the disk devices upon write performed by the write-back processing unit, a recovery processing unit reserves, in the cache memory, a cache stripe area storing data of the entire stripe including the new data which is to be written back, and causes the cache control unit to manage it.

Storage system, control method thereof, and program

A RAID control apparatus comprises at least a cache memory; an update information management table for storing update information; an update information storage unit for storing, in the update information management table, update information by detecting a data update; a reference value generation unit for generating a reference value expressing a load of a write back processing by using a Small Write method and a Read & Bandwidth Write method based on the update information; a write method determination unit for determining a write method according to the reference value and a write unit for carrying out a write processing, in order to provide a write back method for a RAID apparatus capable of improving a processing speed at the time of updating even in the case of including the processing of updating a part of data stripes.

Write back method for RAID apparatus

The present invention has been made to obtain a magnetic disk apparatus and the like capable of using a patrol region in the magnetic disk to detect a location in need of maintenance in hardware equipment around the magnetic disk in a separate manner from the disk itself and thereby avoiding useless replacement and operating the magnetic disk apparatus at low cost. In a preventive maintenance detection for a magnetic disk apparatus having a patrol function that uses a patrol region in the magnetic disk to determine the presence/absence of the need of preventive maintenance, a data pattern for detecting crosstalk in hardware equipment around the disk is generated, a write command or read command corresponding to the generated data pattern is executed, and the crosstalk is determined/detected based on the command execution result.

Growing community of inventors

Kawasaki, Japan

Shinya Mochizuki