JPH0282312A - Disk management device - Google Patents

Abstract

PURPOSE:To reduce the load of a system by equalizing contents of a normal file and a backup file to each other without simultaneously updating these files. CONSTITUTION:When the red/write load of the system is reduced, backup data is generated based on a history information in a history information storage part 4 by a backup file contents updating part 11 to update data in a disk device designated as a backup file device. When a prescribed condition is satisfied in the completion state of the backup processing of this disk device a disk designating part 5 is controlled by a normal file switching part 12. Then, the disk device designated as the normal disk means till then is designated as the backup disk device, and the disk device designated as the backup disk device till then is designated as the normal disk device. Thus, the load of the system is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Statement of the Invention] (Field of Industrial Application) The present invention relates to a disk management device used in a computer system or the like.

(Prior art) Normally, in a computer system that has a disk device, it is assumed that data will be lost when the disk device fails.
A so-called dual management system is often adopted, which has a normal disk device that is accessed in a normal state and a backup disk device that is used for backing up this normal disk device.

When updating data, the data is updated on the regular disk device and the backup disk device at the same time. If the regular disk device fails for some reason, the backup disk device is used to prevent business interruption. There is.

(Problem to be Solved by the Invention) However, in the conventional disk management method used in such computer systems, in order to perform data maintenance, the data of files on the normal disk device and the data of files on the backup disk device are The problem is that the load when updating data is high because the data must be updated at the same time.

Also, normally, the disk device to which read/write files are allocated and the disk device to which backup files are allocated are separate, so the access frequency of the disk device to which backup files are allocated is higher than the access frequency of regular files. There is a problem in that the access frequency of the assigned disk device is higher, and the failure rate of the disk device to which normal files are assigned is correspondingly higher.

In view of the above circumstances, the present invention makes it possible to make the contents of regular files and backup files the same without having to update them at the same time, thereby reducing the load on the system, and also making it possible to reduce the load on the regular disk. It is an object of the present invention to provide a disk management device that can average the access frequency of the device and the access frequency of a backup disk device, thereby reducing the failure rate of each disk device.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, a disk management device according to the present invention includes a disk specifying section that specifies one of two disk devices as a normal file device and the other as a backup file device; When it is necessary to write to a normal file device in the process of executing an application program, a normal file content update unit performs a write operation to the normal file device specified by the disk specification unit, and this normal file content update unit A history information generation unit that generates history information indicating the changed content each time the content in the normal file device is changed; a history information storage unit that stores the history information generated by the history information generation unit; and a system load. backup file contents for generating backup data according to the history information stored in the history information storage section and writing the backup data to the backup file device specified by the disk specification section when an update section; when a predetermined condition is met with the backup file content update section completing the content update process for the backup file device, the disk specification section is controlled and the disk was used as a normal file device until then; The present invention is characterized by comprising a normal file switching processing section for changing the designation of the backup file device that has been used as the backup file device to the normal file device.

(Function) In the above configuration, as the application program is executed, data is updated by the normal file content update unit to the disk device designated as the normal file device, and at this time, the history information generation unit updates the changed content. History information indicating this is created and stored in the history information storage section. Thereafter, when the read/write load on the system decreases, backup data is created based on the history information stored in the history information storage section by the backup file content update section, and the disk designated as the backup file device is created. Device data is updated. Then, when the backup processing of the disk device designated as the backup file device has been completed, when a predetermined condition is met, the disk specification section is controlled by the normal file switching section and the disk device is designated as the normal disk device until then. The one that has been designated as the backup disk device will be changed to the backup disk device, and the one that was previously designated as the backup disk device will be changed to the normal disk device.

(Embodiment) FIG. 1 is a block diagram showing an example of a computer system using an embodiment of the disk management device according to the present invention.

The computer system shown in this figure includes a computer 1 that executes application programs 7a to 7n, and a computer 1 that executes application programs 7a to 7n.
A normal disk device, two disk devices 2.3 used as a backup disk device, and a disk that stores updated contents (history information) when the contents of the one used as a normal disk device is updated. Device 4
and application programs 7a to 7.
When executing n, the process is performed using the disk device 2.3 that is designated as the normal disk device at that time, and the processing contents for this disk device are stored in the history file 15 of the disk device 4. do. When this process is finished, the content of the one designated as the backup disk device is updated while referring to the history file 15, and when this update process is finished, the conditions for switching the disk device are met. If so, the one previously designated as the normal disk device is changed to the backup disk device, and the one previously designated as the backup disk device is changed to the normal disk device.

The computer 1 selectively executes a regular file determination table unit 5 that specifies one of the disk devices 2.3 as a regular disk device and the other as a backup disk device, and a plurality of application programs 7a to 7n. An execution unit 8 and a normal unit that detects when update processing for a normal file is required in the execution process of the execution unit 8 and updates the contents of the normal disk device specified in the normal file determination table unit 5. The file updating section 9 is also provided.

Furthermore, this computer 1 includes a history information processing section 10 that detects when a normal file is updated by the normal file updating section 9 and writes the updated content into the history file 15 of the disk device 4 as history information; The history file 1. is activated when the execution unit 8 is not executing a process or when a backup file is not being read or written and is stored in the disk device 4.
a backup file updating section 11 that updates the contents of the one designated as the backup disk device in the normal file determination table section 5 in correspondence with the contents of the two disk devices 2.3 to make the contents of the two disk devices the same; When a predetermined condition is met with the backup file updating unit 11 completing the update of the backup file, the normal file determination table unit 5 is controlled to select the one that has been designated as the normal disk device as the backup disk device. It also includes a disk switching unit 11 for changing the designation of the one previously designated as a backup disk device to a normal disk device.

Next, the operation of this embodiment will be explained with reference to the flowcharts shown in FIGS. 2 to 5.

First, if a plurality of application programs 7a to 7n are selectively executed by the execution unit 8 and an update request for a normal file is generated at this time, the normal file update unit 9 detects this and executes the normal file update request as shown in FIG. Execute file update processing.

In this process, the normal file update unit 9 first updates the execution unit 8
Checks whether a normal file update command has been output from (Step 5TI). If an update command has been output, the normal file update unit 9 checks the normal file determination table unit 5 of the disk device 2.3. A command based on the update command is issued to the disk device designated as the normal disk device to update the contents of the file stored in this disk device (step 5T2).

After this, the normal file update unit 9 checks whether this update process was performed normally or not (step S'T3).
, if this is done normally, the history information processing unit 1
0 (step 5T4).

Further, in the above-described operation, if the normal file update command is not output (step 5TI), the normal file update section 9 skips the above-mentioned normal file update process and the startup process of the history information processing section 10. In addition, in the above-described operation, if the data update process for the normal file is not performed normally (step 5T3),
The normal file update section 9 skips the activation process of the history information processing section 10.

The history information processing section 10, when activated by the normal file updating section 9, executes the history information writing process shown in FIG.

In this process, the history information processing section 10 first creates history information based on the update contents of the normal file executed by the normal file updating section 9 and transfers it to the disk device 4.
(Step 5T5).

After that, the history information processing unit 10 checks whether the backup file updating unit 10 is executing the process (step 5T6), and if it is not executing the process (step 5T).
7) The backup file update unit 11 is activated (step 5T8), and if the process is being executed, the activation process of the backup file update unit 11 is skipped.

The backup file update section 11 executes the backup process shown in FIG. 4 when a startup command is issued from the history information processing section 10.

In this process, the backup file update unit 11 first extracts the data at the beginning address of the history file 15 (step 5T8), and then checks whether this data is history information (step 5T9).

Then, if the data just retrieved is history information, the backup file update unit 11 selects the one specified as the backup disk device by the normal file determination table unit 5, and based on the history information just read out. The backup file of the disk device designated as the backup disk device is updated (step 5T10).

Next, the backup file update unit 11 deletes the history information that has just been processed from the history file 15 (step 5T11), and then executes the above-mentioned process again to check whether there is next history information in the history file 15. Please check.

Then, if there is history information that has not been processed yet, the backup file update unit 11 updates the contents of the backup file specified in the backup disk device based on this history information (steps ST8 to ST5T).
II).

After that, when the processing for all the history information in the history file 15 is completed, the backup file update unit 11
starts the disk switching unit 12 (step S
T12).

When activated by the backup file updating section 11, the disk switching section 12 executes the disk device switching process shown in FIG. 5.

In this process, the disk switching unit 12 first controls the normal file determination table unit 5 to prohibit the file update process for the one designated as the normal disk device (step 5T13), and also executes the previous disk switching process. A check is made to see if a predetermined time period has elapsed since the time (step 5TI4).

Then, if a predetermined time has elapsed since the previous disk switching process was executed, the disk switching unit 12 selects the normal file determination table unit 5 as shown in FIG.
Control the two disk devices 2.3 to change the designation of the one that was previously designated as a normal disk device to the backup disk device, and change the designation of the one that was previously designated as the backup disk device to the normal disk device. (Step 5T15).

Thereafter, the disk switching unit 12 controls the normal file determination table unit 5 to cancel the write prohibition command issued to the normal disk device and restart the write process for the normal file (step ST1 ．．
6).

At this time, if a predetermined time has not elapsed since the previous disk switching process (step 5T14), the disk switching unit 12 skips the above-described disk switching process and performs only the normal file write protection release process.

As described above, in this embodiment, under normal processing conditions, read/write is performed for the disk device designated as the normal disk device.
Create history information based on the write information while executing write processing, write this to history file]-5, and later create a backup file based on the history information stored in this history file 15. Therefore, you can create a backup file without creating a backup file at the same time as a regular file.
This allows the load on the computer 1 to be reduced.

Furthermore, in this embodiment, when the preset disk device switching conditions are met, the one that was previously used as the normal disk device becomes the backup disk device, and the one that was previously used as the backup disk device becomes the backup disk device. Since the switching is made to a normal disk device, the access frequencies of the two disk devices 2.3 can be averaged, thereby reducing the failure rate of the two disk devices 2.3.

〔Effect of the invention〕

As explained above, according to the present invention, a normal file and
You can make the contents of these files the same without updating the backup files at the same time, which reduces the system load and reduces the access frequency of the normal disk device and the backup disk device. can be averaged,
This makes it possible to reduce the failure rate of each disk device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a computer system to which an embodiment of the disk management device according to the present invention is applied, FIG. 2 is a flowchart for explaining normal file update processing of the embodiment, and FIG. FIG. 4 is a flowchart for explaining the history file update process of the embodiment, FIG. 4 is a flowchart for explaining the backup file update process of the embodiment, and FIG. 5 is a flowchart for explaining the disk device switching process of the embodiment. Flowchart, FIG. 6 is a block diagram showing an example of connection after disk device switching processing in the same embodiment. 2.3...Disk device 4...History information storage section (disk device) 5...Disk specification section (normal file judgment table section) 78-7n...Application program 9...
Normal file content update section (normal file update section) 10... History information generation section (history information processing section) 11...
・Backup file content update section (backup file update section) 12... Normal file switching processing section (disk switching section)

Claims (1)

[Claims] (1) A disk specification section that specifies one of the two disk devices as a normal file device and the other as a backup file device, and when it is necessary to write to the normal file device in the process of executing an application program, the disk specification section A normal file content update unit that performs a write operation to the one specified in the file device, and this normal file content update unit generates history information indicating the changed content every time the content in the normal file device is changed. a history information generation unit that stores the history information generated by the history information generation unit; and a history information storage unit that stores the history information generated by the history information generation unit, and backs up the history information stored in the history information storage unit when the system load becomes small. a backup file content update unit that generates data and writes the backup data to the backup file device specified by the disk specification unit; and the backup file content update unit performs content update processing for the backup file device. When predetermined conditions are met in the completed state, the disk specification section is controlled to make the one that was previously used as a normal file device the backup file device, and the one that was used as the backup file device until then. a normal file switching processing unit that causes the specification to be changed to a normal file device;
A disk management device comprising: