JPH07146759A - Disk array device - Google Patents

Abstract

PURPOSE:To provide a disk array device which is capable of shortening the time required for a backup. CONSTITUTION:At the time of a writing, data is divided by a fixed unit in a disk array control part 13, the data is successively supplied to disk drives 15A to 15D and it is written, and the parity prepared in a control part 13 is supplied to a disk drive 15E and it is written. At the time of a reading, data is reconstructed by the data and parity read from the drives 15A to 15g. Memory devices 18A to 18E for backup corresponding to each of the drives 15A to 15E are provided. At the time of a backup, the divided data and parity written in the drives 15A to 15E are supplied to the memory devices 18A to tag in parallel without performing a processing via an interface 17 and they are written. Thus, the time required for the backup can be shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk array device having a plurality of disk drives operating in parallel.

[0002]

2. Description of the Related Art In recent years, the performance and reliability of computers have improved significantly, and even as a data storage device,
High speed, large capacity and high reliability are required. A disk array device has been conventionally proposed as a data storage device that satisfies these requirements. FIG. 2 shows a configuration example of a conventional disk array device.

In FIG. 2, reference numeral 10A denotes a disk array device as a whole.
The SCSI port 11 of the
It is connected to a SCSI adapter 31 provided in the host system (host computer) 30. At the time of writing, the SCSI adapter 31 and S from the host system 30
Data is transferred to the SCSI port 11 via the CSI bus 20.

The data transferred to the SCSI port 11 is transferred to the disk array controller 13 via the SCSI controller 12. In the disk array controller 13, the transferred data is divided into fixed units, and the divided data (hereinafter referred to as “divided data”) is stored in the controller 14
Is sequentially supplied to the disk drives 15A to 15D via the disk to be written.

In the disk array controller 13, a parity is created for each data divided in parallel, and the created parity is supplied to the disk drive 15E via the controller 14 and written at the same time when the data is written.

By writing the parity in the disk drive 15E in this manner, the disk drives 15A to 15A
Even if one of the Ds cannot read the data,
Depending on the read data of the other readable disk drive and the read data of the disk drive 15E,
You can recover unreadable data on the disk drive.

Next, at the time of reading, the disk drive 1
The divided data and the parity read by 5A to 15E are transferred via the controller 14 to the disk array controller 13
Is supplied to. The disk array controller 13 reconstructs the data from the divided data and the parity. The data reconstructed by the disk array control unit 13 is the SCSI controller 12, SCSI port 11, S
It is transferred to the host system 30 via the CSI bus 20 and the SCSI adapter 31.

Reference numeral 16 is a backup memory device including a tape drive, for example. At the time of backup, the data reconstructed by the disk array controller 13 is transferred to the memory device 16 via the SCSI controller 12 and written in the same way as at the time of reading described above. As a result, the data written in the disk drives 15A to 15D is backed up.

[0009]

As described above, in the conventional disk array device, the disk drive 15
When backing up the data written in A to 15D, the disk array control unit 13 uses the divided data and parity read by the disk drives 15A to 15E.
After the reconstruction, the data is transferred to the backup memory device 16 via the SCSI controller 12 for writing, and there is a problem that it takes a long time for the backup.

Therefore, the present invention provides a disk array device which can reduce the time required for backup.

[0011]

SUMMARY OF THE INVENTION The present invention has a plurality of disk drives that operate in parallel and divides data into a plurality of disk drives by writing in a predetermined unit at the time of writing, and at the time of reading, a plurality of disk drives. In a disk array device configured to reconstruct data from the data read in step 1, a plurality of backup memory devices are provided for each of the plurality of disk drives.

[0012]

In the present invention, since the backup memory device is provided for each of the plurality of disk drives of the disk array device, the divided data and parity written in each disk drive are processed at the time of backup. It is possible to supply the data to a corresponding backup memory device without writing and write the data, and it is possible to shorten the time required for the backup.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a disk array device according to the present invention will be described below with reference to FIG. In FIG. 1, parts corresponding to those in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, reference numeral 10 denotes the disk array device of the embodiment as a whole, and 18A to 18E are backup memory devices each composed of a tape drive or the like, and these memory devices 18A to 18E are interfaces 17. Disk drive 1 through each
5A to 15E. These memory devices 18A to
The operation of 18E is controlled by the controller 14.

The present example is constructed as described above, and the other parts are constructed similarly to the example of FIG.

In this example, at the time of backup, the data read by the disk drives 15A to 15E are supplied to the memory devices 18A to 18E in parallel via the interface 17 and written therein without any processing.

The data written and backed up in the memory devices 18A to 18E are read out, and the disk drive 15A is read out via the interface 17 respectively.
~ 15E can be supplied and written.

As described above, according to this example, at the time of backup, the data read by the disk drives 15A to 15E are not processed and the memory device 1 is not processed.
Since the backup is performed by being supplied to and written in parallel to 8A to 18E, the time required for the backup can be significantly reduced as compared with the conventional case.

For example, the disk drives 15A-15
When the memory capacity of E is 3 Gbytes, the time required for backup is about 7 hours in the related art, while it is about 2 hours in this example.

Although the above embodiment has five disk drives 15A to 15E,
It is needless to say that the present invention can be similarly applied when the number of disk drives is other.

[0021]

According to the present invention, since a backup memory device is provided for each of a plurality of disk drives, the backup memory corresponding to each of the disk drives is not processed at the time of backup. The data can be supplied and written in parallel to the devices, and the time required for backup can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of a disk array device according to the present invention.

FIG. 2 is a block diagram showing a configuration of an embodiment of a conventional disk array device.

[Explanation of symbols]

 10 disk array device 13 disk array control unit 15A to 15E disk drive 18A to 18E backup memory device

Claims (2)

[Claims] 1. A plurality of disk drives that operate in parallel are provided, and when writing, data is divided into a plurality of disk drives and written in a predetermined unit, and when reading, data is read from the data read by the plurality of disk drives. In the disk array device configured to perform the rebuilding, the disk array device is provided with a plurality of backup memory devices corresponding to the plurality of disk drives. 2. The disk array device according to claim 1, wherein the backup memory device is a tape drive.