JP3022011B2 - Data backup system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backup system for transferring data in an auxiliary storage device such as a magnetic disk to backup storage means such as a magnetic tape.

[0002]

2. Description of the Related Art Generally, a computer has an external storage device such as a magnetic disk, and stores various data therein. Then, the data stored in the external storage device is changed by executing the business program. However, the storage contents of an external storage device such as a magnetic disk may be lost due to some failure. For this reason, it is necessary to take measures against such a situation in the computer. Therefore, at a predetermined frequency, for example, at the end of a job, the data in the magnetic disk is transferred to another recording medium such as a magnetic tape for backup.

[0003]

However, depending on the type of business, the amount of data is large, and when all data is backed up, the time becomes extremely long, and the time required for end processing becomes long. There was a point.

On the other hand, JP-A-64-8848 discloses that
Instead of backing up all data, only the data that has changed is backed up.
However, even with this method, the backup process is performed when the normal business is completed and the data in the magnetic disk is settled down.Therefore, the backup must be performed after the normal business process is completed. There is a problem that extra processing must be performed. Further, if the backup of only the updated portion is repeated, the number of backup files increases, and there is a problem that management of the files becomes complicated.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a data backup system capable of backing up data by parallel processing at the time of normal business execution.

[0006]

SUMMARY OF THE INVENTION A backup system according to the present invention comprises a business program executing means for executing a business program, an auxiliary storage means for storing data handled in a business, and all data stored in the auxiliary storage means. Backup program executing means for backing up the data in the backup storage means, update location storage means for storing the location of the data whose contents have been changed by execution of the business in the data of the auxiliary storage means, and this update location In a backup system having a partial backup unit for backing up data of an updated portion stored in a storage unit, the operation by the operation program execution unit and the backup by the entire backup program execution unit are performed in parallel, and Backup program After the backup is complete by the line means,
The backup of the update location stored in the update location storage means is performed by the partial backup means.

Further, the backup system according to the present invention provides a business program executing means for executing a business program, and an overall backup for backing up data stored in an auxiliary storage means for storing data handled in the business to a backup storage means. a program execution unit, a backup portion for storing a business by business program executing means, and parallel processing means for controlling so that parallel processing of backup in the entire backup program execution means, a portion of backed up by the whole backup program execution means is executed When updating the data in the auxiliary storage means during execution of the business program with the storage means, the updated location is compared with the backup location, and it is determined whether or not the location that has already been backed up is updated. If the access to the update determination means and the auxiliary storage means is for a location where the backup has been made, the update location storage means for recording data on the updated location and the update location storage means A partial backup means for backing up data of the update location in the auxiliary storage means on the basis of the update location being updated, and after the backup by the whole backup program execution means is completed, the partial backup means performs backup of the update location. It is characterized by.

[0008]

As described above, in the present invention, the normal operation and the backup are performed in parallel. Therefore, most of the backup processing can be performed during the processing of normal business. Then, the part rewritten after the backup by the parallel processing is stored in the update location storage means, so that this part can be backed up after the operation is completed. This backup amount is only a part of the rewriting performed at the time of the parallel processing, and is very small as compared with the entire data amount. Therefore, the addition of the processing time at the end is very small.
Also, the backup file is only divided into two, and its management is easy.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating the overall configuration of the data backup system according to the embodiment. This system has, as auxiliary storage means, a magnetic disk 12 for storing data handled in business and a magnetic tape 14 for backing up and storing data in the magnetic disk 12. The job processing unit 16 is a part that performs a normal job, and data generated by this is stored on the magnetic disk 12. This operation includes, for example, processing for medical affairs, and the storage of various data on a patient and the recording of medical treatment on the patient are recorded on the magnetic disk 12.

The system includes an overall backup processing unit 18
And a partial backup processing unit 20. The data on the magnetic disk 12 can be downloaded to the magnetic tape 14 by the operation of these processing units 18 and 20. The update management unit 22 also stores information on data changed portions in the magnetic disk 12 after the backup that occurs when both the business processing in the business processing unit 16 and the full backup processing by the full backup processing unit 18 are performed in parallel. It is for managing.

The partial backup processor controls the backup of necessary data based on the data of the update manager 22. The update management unit 22 stores an update management memory 24 for storing data on a changed portion of the contents of the magnetic disk 12 after the entire backup processing, and information about the position of the magnetic disk 12 currently backed up by the entire backup processing unit 18. Is connected to the limiter storage unit 26 that stores the data. The overall control unit 28 includes the business processing unit 16 and the overall backup processing unit 18.
It controls the entire system, such as controlling the parallel processing of. The keyboard, display, and the like are not shown.

FIG. 2 is a flow chart for inputting and outputting data to the magnetic disk 12. First, when a command to access the magnetic disk 12 is issued, the overall control unit 28 determines whether the command is a command for reading (reading) or a command for writing (writing) (S1). If it is a read command, the contents of the magnetic disk 12 at the address corresponding to the read command are read (S
2). Next, it is determined whether or not this magnetic disk read is a request from the full backup program (S
3). If the request is not a request from the whole backup program, the process is terminated because no special process need be performed for the backup. On the other hand, if the command is a magnetic disk read command in response to a request from the whole backup program, the process is transferred to the update management unit 22. The update management unit 22 first determines whether this request is the first request (S4). If this is the first request, the contents stored in the update management memory 24 and the limiter storage unit 26 are reset (S5). If this is the first request, this is at the start of the full backup process and the update management memory 2
4 and the limiter storage unit 26 must of course be in the initial state.

[0013] The limiter storage unit 26 adds the read length of the current data read to the previous storage content as the storage content of the limiter storage unit 26 even if the request is not the first request, and stores the limiter storage unit in the final address of the magnetic disk where the backup was performed. 26 is updated (S6). In this way,
When a magnetic disk read is performed by a request from the whole backup program, the contents in the limiter storage unit 26 are sequentially updated, and the contents stored in the limiter storage unit 26 are always stored on the magnetic disk 12 that has been backed up. It corresponds to the address. In this flowchart, since only the data input and output portions to the magnetic disk 12 are shown, the backup process itself is not described. However, when the whole backup processing unit 18 executes the whole backup process, The data obtained by the magnetic disk reading in S2 described above is written on the magnetic tape 14.

On the other hand, if the command is a write command to the magnetic disk in S1,
2 is written with data corresponding to the instruction (S7). Then, it is determined whether or not the entire backup program is operating (S8). This determination is performed by the overall control unit 28. The overall control unit 28 controls the execution of the business process and the overall backup process by time sharing.
This determination can be made easily. Then, if the whole backup program is not running (S8), the process is terminated, and if it is running, the process is moved to the update management unit 22. The update management unit 12 compares the address of the current disc write command with the limiter stored in the limiter storage unit 26 (S9). Here, the limiter stored in the limiter storage unit 26 indicates the address in the magnetic disk 12 that has been backed up by the whole backup program, and by this comparison, the execution of the current write command has already completed the backup. It can be determined whether it is for the part that has been backed up or for the part to be backed up.

In S9, if it is smaller than the write address limiter, the contents stored in the update management memory 24 are changed (S10). That is, the update management memory 2
4, the content of the portion corresponding to the currently written portion is rewritten with data indicating that partial backup by the partial backup processing unit 20 is necessary. On the other hand, S9
In the case where the write address is larger than the limiter address, backup of the written data will be performed from now on, so that partial backup is not necessary. Therefore, the process ends without updating the data in the update management memory 24.

As described above, in this embodiment, since the business process and the whole backup process are performed in parallel, no special time is required for the whole backup process. Then, for the portion of the magnetic disk whose data content has been changed by the business program after performing the entire backup process, the position is stored in the update management memory 24. Therefore, in the partial backup processing by the partial backup processing unit 20, if the area indicated in the update management memory 24 is backed up, the complete data backup at that time can be performed.

That is, the partial backup processing unit 20
Functions as an end process after the normal business process is completed. This partial backup process is performed by transferring data on a portion requiring backup described in the update management memory 24 to the magnetic tape 14. As a result, of the data stored on the magnetic disk at the end of the job, data different from the backup data obtained by the whole backup is partially backed up. The data for associating the whole backup data with the partial backup data is also stored at the time of the partial backup.

As described above, according to the present embodiment, the business process and the whole backup process can be performed as time-division parallel processes, so that no special time is required for the whole backup process and efficient backup is performed. It can be performed. Then, in order to perform the parallel processing of the business program and the whole backup, the contents of the magnetic disk 12 may be rewritten by executing the business program after the whole backup. However, according to this embodiment, since the position of the rewritten portion is stored in the update management memory, the data can be backed up by the partial backup process. Therefore, if both the full backup and the partial backup data are used, all data in the magnetic disk 12 can be restored. The amount of data that must be stored by the partial backup process is only the data rewritten after the entire backup. If the start of the full backup process is made as close as possible to the end of the operation, the amount of data changed thereafter will be very small. During parallel processing, the probability that data contents are rewritten after a full backup is 50%.
It is. Therefore, even if only this part is considered, the work time to be performed after the end is reduced by 50% as compared with the case where all backups of the updated part are performed after the end of the work. As described above, according to the present embodiment, the work time that must be added in the end processing can be made very short.

[0019]

As described above, according to the data backup system of the present invention, the execution of the business program and the execution of the whole backup program can be performed by parallel processing. Thus, data backup can be performed during the normal computer operation time for executing the business program. Further, the inconsistency between the backup data caused by the parallel processing and the data stored in the magnetic disk can be resolved by the partial backup processing, so that the same complete backup processing as in the related art can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an overall configuration of an embodiment.

FIG. 2 is a flowchart illustrating operations of input and output processing for a magnetic disk.

[Explanation of symbols]

 REFERENCE SIGNS LIST 12 magnetic disk 14 magnetic tape 16 business processing unit 18 whole backup processing unit 20 partial backup processing unit 22 update management unit 24 update management memory 26 limiter storage unit 28 overall control unit

Claims (2)

(57) [Claims] 1. A business program execution means for executing a business program, an auxiliary storage means for storing data handled in a business, and a whole backup for backing up all data stored in the auxiliary storage means to a backup storage means. Program execution means, update location storage means for storing the location of the data whose contents have been changed by execution of the business in the data of the auxiliary storage means, and update location data stored in the update location storage means in backup system having a partial backup unit that backs up the business by the business program execution means, and performs in parallel a backup in the entire back <br/> up program execution means, the backup by the entire backup program execution means After finishing, A data backup system for backing up the update location stored in the update location storage means by backup means. 2. A business program execution means for executing a business program, a whole backup program execution means for backing up data stored in an auxiliary storage means for storing data handled in a business to a backup storage means, and a business program execution. and business by means, a parallel processing unit that controls to parallel processing of backup in the entire back <br/> up program execution means, and a backup location storage means for storing the locations backed up by the whole backup program execution means is executed An update determining unit that compares an updated location with a backup location when updating data in the auxiliary storage unit during execution of a business program, and determines whether or not an update is performed on a location that has already been backed up; For auxiliary storage means In the case where the access to the backup location has been made, the update location storage means for recording data on the update location, and the update location stored in the update location storage means, A data backup system comprising: a partial backup unit that backs up data of an update location in an auxiliary storage unit; and a backup of the update location is performed by the partial backup unit after the backup by the full backup program execution unit is completed.