JPH03122728A - Saving/restoration system - Google Patents

Abstract

PURPOSE:To reduce the capacity of saving files and to shorten restoration processing time by restoring a page image saved in an increment file used for the current saving processing out of two increment files on an auxiliary storage device. CONSTITUTION:A page number collecting means 2 reads in a journal file 1 and collects the page number of an updated page in the file stored in the auxiliary storage device 10 based upon the contents of the file into each updated page. A saving processing means 3 reads in a page image corresponding to the page number collected by the means 2 from the file stored in the device 10, saves the read file into the increment files 6, 7 and also saves page images whose page numbers are not collected and the page numbers into the files 6, 7. A restoration processing means 4 restores the files saved in all saveing files 8 on the device 10 and then restores the page images also on the device 10. Consequently, the capacity of saveing files can be reduced and the restoration processing time can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an evacuation and restoration method for evacuation and restoration of files on an auxiliary storage device.

[Conventional technology]

If a file on the auxiliary storage device is saved on another medium and it becomes necessary to restore the file due to a file failure, etc., the file on the auxiliary storage device can be restored using the file saved on the other medium. Restoring data has been carried out for a long time, and there are five conventional saving and restoring methods of this type as follows.

The first conventional method is to periodically or as needed save all data files on the auxiliary storage device to another medium, and when it becomes necessary to restore the files, save them to another medium. The files are restored by outputting all the saved data files to the auxiliary storage device.

The second conventional method is to save all data files on the auxiliary storage device to another medium once, then save only the journal file that stores updated file contents, and then restore the files. When it becomes necessary, files are restored on a record-by-record, page-by-page, or file-by-file basis. Restoration in units of records is performed by outputting all data files saved in separate media to the auxiliary storage device, reading update records from the journal file, and outputting the read update records to the auxiliary storage device. Page-by-page or file-by-file restoration is performed by outputting all data files that have been evacuated to a separate medium to the auxiliary storage device, and then restoring the updated page images or updates of pages that have been updated based on all data files and journal files. This is done by creating an updated file image of the updated file, and outputting the created updated page image or file image to the auxiliary storage device.

The third conventional method is to save all data files on the auxiliary storage device to another medium once, then save the updated files file by file to another medium, and when it becomes necessary to restore the files, After outputting all the data files that have been saved to a separate medium to the auxiliary storage device, the refile is restored by outputting the saved updated file image to the auxiliary storage device.

The fourth conventional method is to save all data files on the auxiliary storage device once to another medium, and then collect updated page information each time the data file is updated, periodically or as needed. Only pages that have been updated based on updated page information that has been saved are saved page by page to a separate medium, and if files need to be restored, all data files saved to the separate medium are saved to the auxiliary storage device. After outputting to
The file is restored by outputting the saved updated page image to the auxiliary storage device.

The fifth conventional method is to save all data files on the auxiliary storage device once to another medium, and then collect updated pages from the journal file periodically or as needed, and based on the collected updated page information. If you save only the updated pages page by page to another medium, and if you need to restore the files, output all the data files saved to the other medium to the auxiliary storage device, and then save them. The file is restored by outputting the updated page image to the auxiliary storage device.

[Problem to be solved by the invention]

Each of the conventional methods described above has the following drawbacks.

In the first conventional method, all data files are saved to a separate medium periodically or as needed, which has the disadvantage that the capacity of the save file and the save processing time become enormous.

The second conventional method saves only the journal file after all data files have been saved once, so the capacity of the save file and the save processing time can be reduced compared to the first conventional method. However, when restoring in units of records, it is necessary to perform the restoration process the same number of times as the number of updated records, and when restoring in units of pages or files, it is necessary to restore from all data files and journal files that have been evacuated. This method requires processing to create an updated page image of an updated page or a file image of an updated file, resulting in a disadvantage that the restoration processing time becomes longer.

In the third conventional method, updated files are saved in file units, so pages that have not been updated are also saved, resulting in a problem that the capacity of the saved file becomes unnecessarily large.

The fourth conventional method saves updated pages page by page, so it is possible to reduce the size of the save file compared to the third conventional method, but as the number of times the save process increases, There is a problem that it is difficult to make the capacity of the saved file sufficiently small because there is a possibility that the updated page image for the page will be saved many times. Furthermore, in the fourth conventional method, since the process of collecting updated page information is performed every time a data file is updated, there is a drawback that the overhead during running of a business program becomes large.

The fifth conventional method performs evacuation processing based on journal files, so it does not increase the overhead when running business programs, but as with the fourth conventional method, when the number of evacuation processing increases, the same page There is a problem in that it is difficult to reduce the capacity of the saved file to a sufficiently small size because the updated image for the file may be saved many times.

SUMMARY OF THE INVENTION An object of the present invention is to reduce the capacity of a save file and shorten the restoration processing time without increasing the overhead when running a business program.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an auxiliary storage device in which files are stored, a storage medium having all evacuation files from which the files stored in the auxiliary storage device are evacuated, and a storage medium in which the files are saved in the storage medium. In a system equipped with a journal file that sequentially accumulates updated contents of the file after it has been evacuated, two incremental files are provided in the storage medium, and the journal file is read and the updated contents are stored based on the contents of the journal file. a page number collection means for collecting page numbers of updated pages in a file on an auxiliary storage device, one for each updated page; and a page image corresponding to the page number collected by the page number collection means. is read from a file on the auxiliary storage device, the read page image is associated with its page number, and is saved to the incremental file that was not used in the previous saving process among the two incremental files, and Page images that have been saved to the incremental file used in the previous saving process among the two incremental files, and for which the corresponding page numbers were not collected by the page number collecting means, and their page numbers. evacuation processing means for correlating and evacuation of the files to an incremental file that was not used in the previous evacuation process among the two incremental files, and restoring the files saved to the all evacuation file onto the auxiliary storage device. and a restoration processing means for restoring the page image saved in the incremental file used in the current saving process of the two incremental files onto the auxiliary storage device.

[For production]

The page number collection means reads the journal file,
Based on the contents, the page numbers of the updated pages in the file on the auxiliary storage device are collected one by one for each updated page.

The saving processing means reads the page image corresponding to the page number collected by the page number collecting means from the file on the auxiliary storage device, associates the read page image with the page number, and saves the previous one of the two incremental files. A page image that is saved in an incremental file that was not used in the process and also saved in an incremental file that was used in the previous save process among the two incremental files, and that is a page that corresponds to the page number collection means. 2. Page images whose numbers were not collected and their page numbers.
The data is saved to one of the two incremental files that was not used in the previous save process.

The restoration processing means restores the files saved in the all-saved files onto the auxiliary storage device, and then restores the page images saved in the incremental file used in the current saving process among the two incremental files. Restore to auxiliary storage.

〔Example〕

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, which includes a journal file 1, page number collection means 2, save processing means 3, restoration processing means 4, input/output processing means 5, and two incremental files. 6.7 and all the saved files 8 are provided, and an auxiliary storage device 10. In this figure, solid line arrows indicate the flow of data during the save process, and broken line arrows indicate the flow of data during the restore process.

The page number collecting means 2 has a function of reading an update record from the journal file 1 and adding the page number of the updated page obtained based on the contents to the saving processing means 3. The saving processing means 3 passes the page number passed from the page number collecting means 2 to the input/output processing means 5 and reads the page image of the corresponding page from the auxiliary storage device 10.
A function to write the read page image and its page number to an incremental file (referred to as a new incremental file) used for the current backup process among the two incremental files 6.7, and a function to write the previous backup among the incremental files 6.7. Page images that have been saved in incremental files used in processing (referred to as old incremental files) and whose corresponding page numbers have not been collected by the page number collection means 2, and their page numbers. It has a function to write to a new incremental file among the incremental files 6.7. The restoration processing means 4 has a function of reading all the saved files 8, outputting them to the auxiliary storage device 10 using the input/output processing means 5, and inputting the saved page images to a new incremental file among the incremental files 6.7. It has a function of outputting to the auxiliary storage device 10 using the output processing means 5.

FIG. 2 is a flowchart showing a processing example of the page number collection means 2;
FIG. 3 is a flowchart showing an example of processing by the save processing means 3, and FIG. 4 is a flowchart showing an example of processing by the restoration processing means 4. The operation of this embodiment will be described below with reference to each figure.

First, the saving process will be explained with reference to FIGS. 1, 2, and 3. In the following explanation, the incremental file 6 is assumed to be the old incremental file, and the incremental file 7 is assumed to be the new incremental file.

In FIG. 2, the page number collecting means 2 performs processing step 2.
1 reads one update record from journal file 1. In processing step 22, it is determined whether the file END of journal file 1 has been reached, and the file END is determined.
If it is determined that the file has reached END, processing step 26, which will be described later, is executed, and if it is determined that the file is not END, processing step 23 is executed. In processing step 23, based on the update record read from the journal file 1 in processing step 21, the page number of the page containing the update record is searched. Here, since information indicating the page number is included in the update image of the update record, the page number search can be realized by extracting the information.

In the next processing step 24, it is checked whether the page number retrieved in the processing step 23 is registered in a page number table (not shown) provided inside the page number collection means 2, and if it is registered. If it is not registered, execute process step 21 again, and if it is not registered, execute process step 2.
After executing step 5, process step 21 is executed again. Here, the page number table is a table for arranging and storing page numbers in ascending order, and even if there are n update records for the same page in the journal file 1, Incremental file 6
Alternatively, it is used to save to the incremental file 7 only once. In processing step 25, the page numbers retrieved in processing step 23 are registered in the page number table in ascending order.

Then, if the above-mentioned processing is performed up to the file END of journal file 1 (the judgment result in processing step 22 is yes), the page number collection means 2 stores the contents of the page number table in which the page numbers of the updated pages are registered in ascending order. processing step 26).
, ends the process.

When the save processing means 3 receives the contents of the page number table from the page number collection means 2, it starts the process shown in the flowchart of FIG. Turn on the incremental file read switch FR3. Next, in processing step 32, the page number table read switch TR
5 is ON, and if it is ON, processing step 33 is executed, and if it is OFF, processing step 36, which will be described later, is executed. In processing step 33, one page number is extracted in ascending order from the contents of the page number table sent from journal file l, and it is sent to register TPN, and in the following processing step 34, the page number is written to the page number table. Check whether all page numbers on the page have been retrieved. and,
If it is determined that not all have been taken out, proceed to processing step 3.
6, and if it is determined that all have been taken out, in processing step 35, the max predetermined in the register TPN is
After setting the value and displaying that all page numbers written in the page number table have been retrieved, processing step 36 is executed.

In processing step 36, the old incremental file read switch F
It is checked whether R3 is ON or not, and if it is ON, processing step 37 is executed, and if it is OFF, processing step 310, which will be described later, is executed.

In processing step 37, the page numbers of the pages whose page images are saved are read one by one in ascending order from the old incremental file 6, and are set in the register FPN.
Check whether all page numbers written in the page have been read out.

If it is determined that not all have been read out, processing step 310 is executed; if it is determined that all have been read out, a predetermined max value is set in the register FPN in processing step 39, and then processing step 310 is executed. .

In processing step 310, in order to merge the page number table and the page number read from the old incremental file 6, the contents of register TPN and the contents of register FPN are compared. Here, if TPN > F P N, it means that the page corresponding to the page number read from the old incremental file 6 has not been updated after the previous save processing, and if TPN < FPN, the page corresponding to the page number read from the old incremental file 6 has not been updated. This means that the page corresponding to the page number extracted from the table contents has been updated for the first time after all evacuation processing, and the TPN
If =FPN, it means that the page corresponding to that page number was updated after the previous save process.

Therefore, by performing the following process based on the determination result of processing step 310, it is possible to save only the latest page image of a page that has been updated after saving all files to the new incremental file 7.

That is, if it is determined in processing step 310 that TPN>FPN (the page corresponding to the page number read from the old incremental file 6 has not been updated after the previous save processing), the page read from the old incremental file 6 After outputting the number and page image to the new incremental file 7 (processing step 311), in order to read the next page number from the old incremental file 6, the page number table read switch TR3=OFF, the old incremental file read switch FR3
-ON processing step 312), processing step 32
Return to Here, old incremental file read switch FR3
The reason why only the page number is set to ON is that the page number extracted from the contents of the page number table has not been processed yet and there is no need to newly read it.

In addition, if it is determined in ζ processing step 310 that TPN<FPN (when the page corresponding to the page number extracted from the contents of the page number table is updated for the first time after saving all files), the page number extracted from the contents of the page number table is sent to the input/output processing means 5 to instruct the retrieval of the page image corresponding to the above page number from the auxiliary storage device 10, and the reception receives the page image retrieved by the input/output processing means 5 (processing step 316). After outputting the captured page image and its page number to the new incremental file 7 (processing step 317), in order to retrieve the next page number from the page number table, turn on the page number table read switch TR3 and read the old incremental file. Switch FR3-OFF processing step 31
8), return to processing step 32. Here, only the page number table read switch TR3 was turned ON because the page number extracted from the daily incremental file 6 was
This is because it has not been processed yet and there is no need to newly read it.

Furthermore, if it is determined that TPN=FPN in processing step 310 (if the page corresponding to the page number extracted from the contents of the page number table has been updated after the previous evacuation process), the contents of FPN are predetermined. Max
Step 319)
, if it is determined that the max value has been reached, the process is terminated; if it is determined that the max value has not been reached, the page number extracted from the contents of the page number table is sent to the input/output processing means 5 and the above An instruction is given to retrieve the page image corresponding to the page number from the auxiliary storage device 10, and the input/output processing means 5 receives the retrieved page image (
After outputting the received page image and its page number to the new incremental file 7 (processing step 313), a page number table read is performed to read the page number from both the page number table and the old incremental file 6 (processing step 314). Switch TR3=ON, old incremental file read switch FR3=ON Process step 315
), the process returns to step 32.

As explained above, in the saving process, the page number collecting means 2 collects the page number of the updated page from the journal file 1, and the saving processing means 3 combines the page number with the page number read from the old incremental file 6. Based on this, the page that has been updated after the previous evacuation process and the page that has been saved to the old incremental file 6, but has not been updated since the previous evacuation process, is found, and the page that has been updated after the previous evacuation process is found. For pages that have been saved in the old incremental file 6, the page image is read from the auxiliary storage device 10, and the read page image and its page number are output to the new incremental file 7. This is achieved by outputting the page image read from the old incremental file 6 and its page number to the new incremental file 7 for pages that have not been updated after the saving process.

Next, the restoration process will be explained with reference to FIGS. 1 and 4.

In FIG. 4, the restoration processing means 4 first reads all saved files 8 from the saved medium 9 in processing step 41, and outputs the read all saved files 8 to the auxiliary storage device 10 using the input/output processing means 5. .

At this stage, the data files in the auxiliary storage device 10 are restored to the image at the time when all files were saved periodically or at an appropriate time. In the next processing step 42, the page number and page image for one page are read from the new incremental file 7, and in the following processing step 43, it is determined whether the page numbers and page images of all the pages stored in the new incremental file 7 have been read. If it is determined that all the data has been read, the process is terminated, and if it is determined that the data has not been read, processing step 44 is executed. In processing step 44, the page number and page image read in processing step 42 are sent to input/output processing means 5, and then,
Return to processing step 42.

By adding the page number and page image from the restoration processing means 4, the input/output processing means 5 restores the page corresponding to the page number on the auxiliary storage device 10 to the restoration processing means 4.
Write the page image added from. Here, the new incremental file 7 saves only the page number of the page updated after all data files were saved to the all save file 8 and the latest page image of the page, so at this stage, the This means that the page corresponding to the above page number on the storage device 10 has been restored to the latest updated image. In other words, the restoration process for the same page only needs to be performed once.

As explained above, in the restoration process, after outputting all saved files 8 read by the restoration processing means 4 to the auxiliary storage device 9 using the input/output processing means 5, page images saved in the new incremental file 7 are output. This is realized by outputting the input/output processing means 5 to the auxiliary storage device 10.

[Effects of the Invention] As explained above, since the present invention performs the saving process based on the journal file, there is an effect that the overhead during running of the business program is not increased. Furthermore, since the present invention saves only the latest page image of the updated page after all files have been saved, the capacity of the save file can be reduced. Furthermore, since the present invention performs the restoration process on the same page only once for each page, it also has the effect of shortening the restoration process time.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a flowchart showing a processing example of the page number collection means 2, FIG. 3 is a flowchart showing a processing example of the saving processing means 3, and FIG. 4 is a restoration 5 is a flowchart showing an example of processing by the processing means 4. FIG. In the figure, 1... journal file, 2... page number collection means, 3... saving processing means, 4... restoring processing means, 5... input/output processing means, 6, 7. . . . Incremental file, 8 . . . All evacuation files, 9 . . . evacuation medium, 10 . . . auxiliary storage device.

Claims (1)

[Claims] An auxiliary storage device in which files are stored, a storage medium having all evacuation files from which files stored in the auxiliary storage device are evacuated, and after the files are evacuated to the storage medium. In a system equipped with a journal file in which updated contents of the file are sequentially accumulated, two incremental files are provided in the storage medium, and the journal file is read and the update contents are stored in the auxiliary storage device based on the contents. page number collection means for collecting page numbers of updated pages in the file, one for each updated page, and a page image corresponding to the page number collected by the page number collection means in the auxiliary memory. Read from a file on the device, match the read page image with its page number, and save it to an incremental file that was not used in the previous save process among the two incremental files. A page image that is saved in an incremental file that was used in the previous save process in which the corresponding page number was not collected by the page number collecting means is associated with that page number. a saving processing means for saving to an incremental file that was not used in the previous saving process among the two incremental files, and restoring the files saved to the all saved files on the auxiliary storage device; A saving and restoring method, comprising: a restoring processing means for restoring a page image saved in the incremental file used in the current saving process out of two incremental files onto the auxiliary storage device.