JPH0773078A - File copy shift system - Google Patents

Abstract

PURPOSE:To provide a file copy shift system by which a file is shift-processed without stopping a processing for the file and without changing the execution instruction of the processing to the file, and the processing efficiency of a system can be improved. CONSTITUTION:Copy shift source/shift destination file area management tables 10 and 11 including copy address information showing the addresses of shifting parts are provided. An access control means 3 compares an address which is access-requested with a copy address and decides the file to be accessed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file copy transfer system for copying and transferring a file on a secondary storage medium to another secondary storage medium.

[0002]

2. Description of the Related Art In the conventional file copy transfer method, data transfer is performed after the access to the transfer target file is temporarily stopped.

A conventional file copy transfer method will be described with reference to FIG.

In FIG. 2, a file AA24 on the disk device A is a file whose contents are copied and transferred, and such a file is hereinafter referred to as a transfer source file. The file AA25 on the disk device B is a file to which the contents of the file AA24 are copied and transferred to this file. Such a file will be referred to as a transfer destination file hereinafter.

The program 21 is a program for migrating the contents of the file from the disk device A to the disk device B, and the programs 26 and 27 are business programs for carrying out the work by using the file 24.

The file transfer means 22 performs file transfer processing by the program 21, and the access control means 23.
Responds to the file access request to write to or read from the specified file.

Normally, the programs 26 and 27 issue a file access request to the access control means 23 as required, and the access control means 23 accesses the designated file in response to the request.

However, in the case where the program 21 is performing the file copy transfer operation by the conventional method,
Programs, such as the programs 26 and 27, that access the file 24 that is the migration source file that is the copy migration target, suspends the temporary execution, and executes these programs after the copy migration processing ends. Was restarting.

The reason is that the data copied and migrated to the migration destination file must be the latest, and during the copy migration processing, the write operation to the migration source file can be performed on the data that has already been copied and migrated. This is because even if it is performed and updated, it has no meaning unless the corresponding data in the migration destination file is updated.

[0010]

In the conventional file copy migration method described above, the processing for the file must be temporarily stopped at the time of copy migration, and the migrated file is accessed as the secondary medium is changed. There is a problem in that execution instructions (job control language, etc.) for all processes must be changed.

An object of the present invention is to carry out a file transfer process without stopping the process for the file and without changing the instruction to execute the process for the file, thereby improving the processing efficiency of the system. To provide.

[0012]

The file copy migration method of the first invention indicates a file name of a file having a copy migration history, a storage device identifier, a storage position in the storage device, and whether or not copy migration is in progress. A transfer source file area management table that stores transfer source file area status data such as a transfer address and a copy address indicating a position in the file of transferred data, a file name of a transfer destination file, a storage device identifier, and a storage device identifier in the storage device. A migration destination file area management table for temporarily storing migration destination file area status data such as a storage position, a migration flag indicating whether or not copying is in progress, and a copy address indicating an in-file position of migrated data, and the migration source file. A file area management table creating means for creating an area management table and the migration destination file area management table; Migration preparation means for activating the file area management table creating means and setting and updating the migration flag and copy address of the migration source file area management table and the migration destination file area management table; and the migration source file area management table. A transfer end unit that rewrites each data of the copy transfer process end file with the corresponding file data of the transfer destination file area management table and then deletes the corresponding file data of the transfer destination file area management table; When there is an access request to the file, the copy address is referred to, and if the request is a first access request that is an access request to a portion for which copy transfer has not been completed yet, access to the copy transfer source file is made. The request is an access request for the part being copied and transferred. In the case of the access request of No. 2, the file of the copy transfer destination is accessed after the copy transfer of the portion, and when the request is the third access request which is the access request to the copy transferred portion, the copy transfer destination. Access control means for accessing the file, the transfer preparation means, the transfer end means, and the access control means, and file transfer means for processing the file copy transfer.

In the file copy migration method of the second invention, in the method of the first invention, the access control means performs access to the copy migration source file in the case of the first access request, In the case of a read access request, the copy transfer source file is accessed after the copy transfer, and in the case of a write access request, the copy transfer source file and the copy transfer destination file are accessed after the copy transfer. In the case of (1), a read access request is made to the copy migration source file, and a write access request is made to the copy migration source and copy migration destination files.

The file copy migration method of the third invention is characterized in that, in the first and second inventions, the address range of the part being copied is used as the copy address.

[0015]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a file copy migration system of the present invention.

The file copy migration method of this embodiment is shown in FIG.
As shown in FIG. 10, the source file area management table 10 that stores the area status data of the file having the copy migration history is stored.
A destination file area management table 11 for temporarily storing the area status data of the destination file, a file transfer means 6 for performing a file copy transfer processing, and a transfer preparation means 4 for preparing a file copy transfer processing. A transfer end means 5 for performing an end process of a file copy transfer process,
It comprises a file area management table creating means 2 for creating a file area management table of a migration source and a migration destination, and an access control means 3 for performing access processing to the file.

In FIG. 1, the program 1 has a file AA7 on the disk device A and a file AA8 on the disk device B.
The program 12 is a program for executing the file copy transfer, and the program 12 is a program for utilizing the file AA.

The items stored in the migration source file area management table 10 and the migration destination file area management table 11 are the same, and an example thereof is shown in FIG.
In these tables, the file names related to the migration and
The disk device identification number (the migration source in Table 10; the migration destination disk device in Table 11) and the file position that indicates the position of the file in that disk device (if there are multiple extents, multiple files are stored. Flag) and a migration flag that indicates whether the file is currently being migrated (ON if migration is in progress, OFF otherwise), and if it is in transition, the position in the file of the currently copied data. Is stored.

FIG. 4 is a flow chart of the file copy transfer processing of the program 1, FIG. 5 is a flow chart showing the operation of the file transfer means 6, and FIG. 6 is a flow chart showing the operation of the access control means 3.
FIG. 7 is a flow chart showing the operation of the shift preparation means 4, and FIG. 8 is a flow chart showing the operation of the shift end means 5.

The operation of this embodiment will be described with reference to FIGS.

As shown in FIG. 4, the file copy migration processing is performed by the program 1 by the file AA of the disk device A.
The file transfer means 6 is notified of a file transfer processing start request for copying and transferring 7 to the designated file position on the disk device B (steps 41 and 42), and the file transfer means 6 is activated to execute the transfer processing (step 43). finish.

File transfer process start request (step 5)
The file transfer means 6 notified of 1) activates the transfer preparation means 4 (step 52) and prepares for transfer (step 53), as shown in FIG.

As shown in FIG. 7, the transfer preparation means 4 determines whether or not the designated file AA7 is the file that has been the target of the transfer process before, if the copy transfer is not in progress (NO branch of step 71). The request is notified to the file area management table creating means 2 for checking by the file area management table 10 (steps 72 and 73).

In the case of a file that has been the target of the migration process before, the migration source file area management table 10 has already been created, as will be described later.

If the search result of the migration source file area management table 10 indicates that the file AA has not been previously subjected to the migration processing (NO branch of step 741), the file area management table creating means 2 migrates the file AA to the migration source. A file area management table 10 and a migration destination file area management table 11 are created (step 742),
If the search result of the migration source file area management table 10 indicates that the file AA has been previously subjected to the migration processing (YES branch of step 741), the migration destination file area management table 11 is created for this file AA (step 743). ).

When the operation of the file area management table creating means 2 is completed as described above, the migration preparing means 4
In the case of step 742, the area information of the migration source file and the identification number of the disk device A are set in the migration source file area management table 10, and further steps 742, 7
Also in the case of No. 43, the area information of the transfer destination file and the identification number of the disk device B are set in the transfer destination file area management table 11, the transfer flag of each file area management table is turned on, and the initial value is set in the copy address. (For example, 0) is set (step 75), and the copy transition preparation is completed.

Then, returning to step 54 in FIG. 5 of the file transfer means 6, a copy transfer process from the file AA7 of the disk device A to the file AA8 of the disk device B is performed by the access control means 3 to start the copy transfer. (Step 55).

The copy transfer is repeated from the beginning of the file in a predetermined appropriate unit amount (for example, a track) until the entire content of the target file is copied and transferred (loop of steps 52 to 55).

Each time a copy transfer of this unit amount is performed, the file transfer means 6 activates the transfer preparation means 4 (steps 52, 53) and the transfer source file area management table 10 and the transfer destination file area management table 11 are transferred. The data position in the file, that is, a constant value corresponding to the unit amount copied and copied to the copy address is added and updated, and the transfer flag is updated to OFF at the end of the copy transfer (YES branch of step 71, step 76).

In this way, when the transfer of all the data of the transfer target file is completed, the file AA7 on the disk device A is deleted (step 56), and a post-processing request for file transfer is notified to the transfer end means 5 ( In step 57), post-processing is performed (step 58) and the process ends.

As shown in FIG. 8, the migration end means 5 rewrites each data of the file AA of the migration source file area management table 10 with each data of the file AA of the migration destination file area management table 11 (step 81). After that (by doing so, the file having the history of copy migration is always registered in the migration source file area management table 10), the migration destination file area management table 11 is set. Delete (Step 8)
2).

In this way, the copy transfer processing of the file is performed.

Next, the relationship between the copy transfer process of the file and the access process to the transfer target file will be described with reference to the flowchart of FIG. 6 showing the operation of the access control means 3 based on the above example.

It is assumed that the program 12 that executes a job using the file AA issues an access request to the access control means 3 in order to access the file AA.

The access control means 3 first checks whether or not the designated file AA is registered in the migration source file area management table 10 (step 61). If the file is not registered (NO branch of step 61), that is, if the file has no history of the transfer target file, the file AA is originally the disk device A.
, So that it is accessed to satisfy the request (step 66).

When the file AA is registered in the transfer source file area management table 10 (YES branch of step 61), it is judged whether or not the file copy is being transferred by the transfer flag. 62
Of the disk device identification number of the migration source file area management table 10 to determine whether it is before the migration start or after the migration start end, and the disk device indicated by the number is accessed to satisfy the request (step 63). , 64 and 6
6).

When the file transfer is in progress in step 62 (YES branch of step 62), it is checked how much the copy transfer is in progress next, and the first request is an access request to a portion where the copy transfer has not been completed yet. The second case, which is the case of a request or an access request to a part currently undergoing copy transfer
Or otherwise, ie,
Processing is performed separately for the case of the third request which is an access request for the already copied portion.

In the case of the first request, that is, when the address to be accessed is larger than (copied address + α) (where α is the address increment corresponding to the amount of data processed in one copy transfer). If there is (YES branch of step 65), the disk device A is accessed.

In the case of the second request, that is, when the address to be accessed is greater than or equal to the copied address and less than or equal to (the copied address + α) (YE of step 67).
First, the copy transfer of this portion is executed.

In this state, the access request is waiting, the address comparison is retried after the transfer to the copy, and the subsequent operation is the same as that of the third request described later. That is, when reading, the disk device A
In case of writing, access is made to both the disk devices A and B (step 68).

In the case of writing, the reason why both are accessed is that the data of the migration destination file must always be the latest and that the migration source file is also updated to cope with the failure. .

In the case of the third request other than the above, that is,
If the address to be accessed is smaller than the copied address, the disk device A is accessed for reading, and both the disk devices A and B are accessed for writing (step 69).

As described above, in the present embodiment, when a file copy is transferred, the progress of the transfer is managed and the file to be accessed by the business program is determined, so that the business program can be executed even during the file copy transfer. In addition, since the execution instruction of all the processes to the migration file can be changed without any change, the processing efficiency of the system can be greatly improved.

It is obvious that the migration source file area management table described in this embodiment can be used by adding a migration flag and a copy address data indicating an address during copy migration to the normally provided file management table. .

Further, in the present embodiment, as a copy address,
Although the copied address is used, it is obvious that even if the address range being copied is specified, it can be used by changing the judgment formula for determining the file to be accessed.

Further, in the present embodiment, in the above-mentioned second and third cases regarding the access to the file during copy transfer, in the case of reading, the transfer source is set to the transfer source, and in the case of writing, the transfer source and the transfer destination are set. Although it is limited to access to both, this is a limitation in consideration of countermeasures against failures and is not limited to this. That is, it is obvious that it can also be used for reading and writing to the migration destination.

[0048]

As described above, according to the file copy migration method of the present invention, when a file copy is migrated, the progress of the migration is managed and the file to be accessed by the business program is determined. Since the business program can be executed even in, and the execution instructions of all the processes for the migration file can be changed,
This has the effect of significantly improving the processing efficiency of the system.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a file copy migration method of the present invention.

FIG. 2 is a block diagram showing a conventional file copy transfer method.

FIG. 3 is a data storage diagram of a migration source file area management table 10 and a migration destination file area management table 11.

FIG. 4 is a flowchart of file copy migration processing of program 1.

FIG. 5 is a flowchart showing the operation of the file transfer means 6.

FIG. 6 is a flowchart showing the operation of the access control means 3.

FIG. 7 is a flow chart showing the operation of the transition preparation means 6.

FIG. 8 is a flowchart showing the operation of the transition end means 5.

[Explanation of symbols]

 1, 12, 21, 26, 27 program 2 file area management table creating means 3, 23 access control means 4 migration preparing means 5 migration ending means 6, 22 file migration means 7, 24 file AA of disk device A 8, 25 disk File B of device B 10 Source file area management table 11 Destination file area management table

Claims (3)

[Claims] 1. A file name of a file having a copy transfer history, a storage device identifier, a storage position in the storage device, a transfer flag indicating whether or not copy transfer is in progress, and a copy address indicating a position in the file of data that has been transferred. Source file area management table for storing source file area status data, file name of the destination file, storage device identifier, storage position in the storage device, transfer flag indicating whether or not copying is in progress, and transfer Create a migration destination file area management table that temporarily stores migration destination file area status data such as a copy address that indicates the in-file position of completed data, the migration source file area management table, and the migration destination file area management table. File area management table creating means, activating the file area management table creating means, and Migration preparation means for setting and updating the migration flag and copy address of the migration source file area management table and the migration destination file area management table, and each data of the copy migration processing end file of the migration source file area management table Transfer end means for rewriting with the corresponding file data in the file area management table and then deleting the corresponding file data in the transfer destination file area management table, and copying when an access request is made to the file being copied In the case of the first access request that refers to the address and the request is an access request to a part for which the copy transfer has not been completed yet, the copy transfer source file is accessed and the request accesses the part being copy transferred. In the case of the second access request, which is a request, it is duplicated after the copy transfer of that part. Access control means for accessing the copy-destination file and accessing the copy-destination file when the request is a third access request which is an access request for the copy-transferred portion. A file copy transfer method comprising: a means, a transfer end means, and an access control means for controlling the file copy transfer. 2. The access control means accesses the copy transfer source file in the case of the first access request and to the copy transfer source file after the copy transfer in the case of the second access request and the read access request. In the case of a write access request, the copy transfer source file and the copy transfer destination file are accessed after the copy transfer, and in the case of the third access request and the read access request, the copy transfer source file is accessed. 2. The file copy migration method according to claim 1, wherein the file of the copy migration source and the copy migration destination are accessed in the case of a write access request. 3. The file copy transfer system according to claim 1 or 2, wherein an address range of a part being copy transferred is used as a copy address.