JPH02186452A - Data update commit processing system - Google Patents

Abstract

PURPOSE:To reduce communication overhead and to improve processing efficiency by requesting commit processing to a resource control part by a coordinator according to control information concerning data resources corresponding to update information. CONSTITUTION:When a transaction start part 32 receives a begin-TRN instruction issued by an application program 1, the index of update display in the respective control tables of a control table chain 36 is initialized to the display of non-update. When the data update request is issued by started transaction, a first time update processing part 31 receives the request and a correspondent control table address is informed of a control table set part 34 of a coordinator 23. After that, update processing is executed. The control table set part 34 sets the display of the update to the index of the update display and executes the update processing. When a COMMIT instruction is issued by the application program 1, a commit request processing part 34 executes temporary update processing only to the control table where the update is being displayed.

Description

[Detailed Description of the Invention] (Summary) A resource management unit that performs commit processing in a coordinated manner regarding commit processing for data preservation in the case of multiple data updates in a computer that would cause a conflict if not performed at the same time. Aiming at a data update commit processing method that can reduce the communication overhead between the computer and the coordinator, the system consists of a resource management section that manages each data resource such as a database and files, and a coordinator that manages transactions executed by application programs. and in which multiple data updates of the data resource by the transaction are validated at once by a commit process executed by the coordinator requesting the resource management unit at the end of each transaction. , the resource management unit processes an open processing request for the data resource that is executed by the application program before starting the transaction, and also sends necessary control information regarding the commit processing of the opened data resource to the coordinator. each time a data update request for the data resource is processed by the transaction;
The resource management unit notifies the coordinator of an update notification indicating the execution of the process, and the coordinator causes the resource management unit to perform the commit process in accordance with the control information for the data resource corresponding to the received update notification. Configure as required.

[Industrial application field]

The present invention relates to a data update commit processing method in a computer for data preservation in the case of multiple data updates that would cause conflicts if not performed simultaneously.

[Conventional technology]

FIG. 2 is a block diagram showing an example of the configuration of a computer system. The application program 1 initializes control information for accessing data resources such as necessary files and databases by commands such as open FILE and open DB, as illustrated in the figure.
After requesting so-called open processing, for example, begin the transaction that performs the processing to access them.
Start with the TRN command.

A transaction is a unit of processing that is established for the purpose of controlling the processing of multiple data resources to avoid inconsistencies, which would otherwise occur if data updates were not performed at the same time. If there are multiple data updates that need to be updated at once to ensure consistency between multiple data, these data updates are combined into one transaction and the data resource prepared with the above open command is created. As shown in the figure, after requesting updates using -riLe FILE, write DB, etc., the C0rl old T command is configured to be issued.

Instructions issued by the application program 1 that request processing of data resources are issued by the respective resource management units 2a,
2b, etc. shall receive and process it, and open FI
LE and open DB commands are sent to the resource management units 2a and 2b.
The initialization unit 10 executes initialization processing for obtaining buffers and accessing files, etc., and processes -write FILE, write DB, etc. as described later.

Additionally, a coordinator 3 is used to manage transactions and support commit requests for the transactions.
is provided, and the transaction start unit 16 receives the begin TRN command issued by the application program I.
When the transaction is accepted, the management table area for the transaction is initialized and the management table chain 19 described later is prepared.

Next, the write FILEXwrite DB command is
If these are the first update requests in the transaction for each data resource, the first update processing unit 11 such as the resource management units 2a and 2b accepts the request.

The initial update processing unit 11 first sends the temporary update processing unit 13, commit processing unit 14, and recovery processing unit to the management table processing unit 17 of the coordinator 3 as necessary control information related to the subsequent commit processing. 15 of each address and the data resource name such as the file name to be updated, the buffer is cleared, and the update data is stored in the buffer, and the update process ends. In this way, each -rite instruction does not actually update the data resource, but only buffers the updated data.

Note that for the second and subsequent update requests in the transaction, the update processing unit 12 accepts the requests and performs only the update process as described above without notifying the control information.

The management table processing unit 17 of the coordinator 3 creates a management table as illustrated in FIG. Connect and hold.

In the application program l, after completing the series of transaction processing as described above, the COM old T
Since a command is issued to the coordinator 3 to request commit processing, the commit request processing unit 18 performs provisional update processing for each data resource indicated in each management table of the management table chain 19 of the transaction by the resource management unit 2a. ,2
A request is made to the temporary update processing unit 13 of b.

The temporary update processing unit 13 updates each data resource R4, such as a file or database, according to the update content held in the buffer.
While the original data is saved in a and 4b, the updated data blocks are provisionally updated in such a way that they are provisionally updated, and the completion status of each data provisional update is processed as a commit request. Answer part 18.

The commit request processing unit 18 waits for a reply regarding the completion status of the temporary update, and when it receives all the replies indicating that the temporary update corresponding to all the management tables in the management table chain 19 has been successfully completed,
The commit processing unit 14 of the resource management unit 2a, 2b is requested to perform a commit process.

Therefore, the commit processing unit 14 performs a data update on the data resources 4a, 4b, etc. that have been temporarily updated as described above, by, for example, deleting the original data block before the update and validating the data block of the updated data. Complete.

Also, in the commit request processing unit]8 of the coordinator 3,
After issuing a temporary update processing request as described above, if it is detected that even some temporary updates are not completed normally, the resource management unit 2a, 2b is requested to perform the recovery process, and the application program I is notified that the process has been canceled due to an unsuccessful update.
5 restores the data resources 4a and 4b to their original state without any updates by canceling all provisional updates.

[Problem to be solved by the invention]

As is clear from the above explanation, the coordinator 3 uses the necessary resource management units 2a and 2 to process the commit request.
When requesting processing from the temporary update processing unit 13, commit processing unit 14, and recovery processing unit 15 from b, it is necessary to receive control information such as each address and the name of the data resource to be updated, and the data to be updated must be sent to the application. In order to issue and confirm an update request instruction in program l, for each initial data update request in each transaction in application program 1, control information related to necessary update data is sent from resource management units 2a and 2b to coordinator 3. The transfer will take place.

However, processing within an application program is often divided into many transactions, and by sending and receiving the control information for each transaction that includes data update processing as described above, control information for commit is transferred. There is a problem in that communication is a relatively large cause of overhead.

The object of the present invention is to provide a data update commit processing method that can reduce the communication overhead between the resource management unit and the coordinator, which perform commit processing in cooperation as described above.

[Means to solve the problem]

FIG. 1 is a block diagram showing the configuration of the present invention.

The figure shows the configuration of a computer system, 22a, 22b
is application program 1 and coordinator 2
An initialization unit 30, an initial update processing unit 31, an update processing unit 12, a temporary update processing unit 13, a commit processing unit 14, and a recovery processing unit 15, which manage each data resource 4a, 4b according to the request of No. 3.
The coordinator 23 is a resource management unit having a transaction start unit 32, a management table generation unit 33, a management table setting unit 34, a commit processing unit 35, and a management table chain 36.
manages the transactions of the application program 1, and requests the resource management units 22a and 22h to process commit requests.

[For production]

In a computer system, resource management units 22a and 22b manage data resources 4as and 4b such as databases and files, and a coordinator 23 manages transactions executed by an application program l. A plurality of data updates of the data resources 4a, 4b by the transaction are validated at once by a commit process executed by requesting the resource management units 22a, 22b.

The resource management units 22a and 22b process open processing requests for the data resources 4a and 4b that are executed by the application program l before the start of a transaction, and also send necessary control information regarding the commit processing of the opened data resources 4a and 4b to the coordinator. Notify 23,
Furthermore, each time a data update request for the data resources 4a, 4b is processed by a transaction, an update notification indicating the processing execution is sent to the resource management units 22a, 22b.
When processing a commit request, the coordinator 23 performs resource management of the commit process according to the corresponding control information only for the data R sources 4a and 4b corresponding to the received update notification. The request is made to the sections 22a and 22b.

With the above processing method, complete control information regarding commit processing is only notified once when the data resource is first opened by the application engine program, and in each transaction, for example, the management table corresponding to the data resource name that is requested to be updated is Since the notification can be reduced to only the address etc. of
Communication overhead for commit processing is reduced.

〔Example〕

In FIG. 1, parts shown with the same reference numerals as in FIG. are the same as the conventional initialization unit O2 initial update processing unit 11, transaction initiation unit 16, and commit request processing unit 18, except as specifically described below.

In the computer system shown in FIG. 1, the application program 1 executes the open FILE command,
After requesting so-called open processing, which initializes control information for accessing data resources such as necessary files and databases, using the open DB command, etc., a transaction that performs the processing to access them is started using, for example, the begin TRN command. and the above operi
Out of the data resources prepared by the f$ command, write the necessary ones as shown in the figure.
After requesting an update using a DB command or the like, a COM old T command is issued at the end of a series of processes.

The open FILE and open DB commands are processed by the initialization unit 30 of the resource management unit 22a522b, and the initialization process for accessing the data resource is executed as in the conventional case. , the temporary update processing unit 13 and the commit processing unit 1 as control information for the commit processing of the data resource to be opened.
4 and the recovery processing unit 15 and the opened data resource name.

The management table generation unit 33 of the coordinator 23 receives this control information and generates and manages a management table as illustrated in FIG. 3 (I) for holding control information etc. of each opened data resource. It connects to the table chain 36 and passes, for example, the management table address to the resource management units 22a and 22b.

Next, begi issued by application program 1
n When the transaction start unit 32 of the coordinator 23 receives the TRN command, the update display section of each management table of the management table chain 36 for that transaction (
(see FIG. 3 (g))) is initialized to display "not updated".

In the initiated transaction, write FILE
.

When a data update request such as a write DB command is issued, if it is the first update request in this transaction for each data resource, the resource management units 22a and 22b
etc., and notifies the management table setting unit 34 of the coordinator 23 of the management table address corresponding to the data resource name as an update notification to notify that the update request will be processed. , update processing is performed only on the buffer as in the past.

The management table setting unit 34 sets the display of "update" in the update display section of the management table based on the management table address received in the update notification.

For each data resource, the update processing unit 12 accepts the second and subsequent update requests in the transaction and only performs the update processing as described above.

When the application program l finishes a series of transactions and issues a coFI old T command to the coordinator 23 to request commit processing, the commit request processing unit 35 updates the update display section in the management table of the management table chain 36. For only the management table that is displayed as "update", a request is made to the temporary update processing unit 13 of the resource management units 22a and 22b to perform temporary update processing according to the contents of all management tables.

The temporary update processing unit I3 performs temporary update of the data resource as in the past, and returns the completion status. When the commit request processing unit 35 receives all normal completion responses for the temporary updates corresponding to all the management tables with the “update” indication in the management table chain 36, the commit processing unit 1 of the resource management units 22a and 22b
4, and completes the main update of the data as in the past.

Further, if the commit request processing unit 35 detects that even some provisional updates are not completed normally, the resource management units 22a and 22b perform recovery processing for all data resources for which provisional update processing has been requested. A request is made to the unit 15 for recovery processing to cancel all provisional updates and restore the original state without updates.

With the above processing method, for the control information necessary for commit processing, each transaction only needs to initialize and set the update display of the management table, so the communication overhead between the coordinator and resource management unit related to commit processing is reduced. can be reduced.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, in the commit processing for data preservation when multiple data updates are performed that would cause a contradiction if they are not performed simultaneously on a computer, the commit processing is performed in a coordinated manner. This has a significant industrial effect in that the communication overhead between the resource management unit and the coordinator can be reduced and the processing efficiency of the system can be improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is a block diagram showing an example of a conventional configuration, and FIG. 3 is an explanatory diagram of a management table. In the figure, l is an application program, 2a, 2b, 22a, 22b are resource management units, 3.23
is the coordinator, 4a and 4b are data resources, 10.3
0 is the initialization part, I! , 3 is the initial update processing department, 12
13 is an update processing unit, 13 is a temporary update processing unit, 14 is a commit processing unit, 15 is a recovery processing unit, 16.32 is a transaction start unit, 17 is a management table processing unit, 18.35 is a commit request processing unit, 19. 36 is a management table chain, 33 is a management table generation section, and 34 is a management table setting section. Agent Patent Attorney Sadako Igeta, G% Block diagram showing the configuration of the present invention Figure 1 Block diagram showing an example of the conventional configuration Figure 1 Explanatory diagram of the management table Figure 1

Claims (1)

[Claims] Data resources such as databases and files (4a, 4b)
), a resource management section (22a, 22b) that manages each
and a coordinator (23) that manages transactions executed by the application program (1), and when each transaction ends, the coordinator requests the resource management unit to perform a commit process, which causes the data generated by the transaction to be processed. In a computer system that enables multiple data updates of resources at once, the resource management unit (22a, 22b):
Processes an open processing request for the data resource executed by the application program (1) before starting the transaction, and notifies the coordinator (23) of necessary control information regarding the commit processing of the opened data resource. Each time a data update request for the data resource is processed by the transaction, the resource management unit (22a, 22b) notifies the coordinator (23) of an update notification indicating the execution of the process; 23) performs the commit processing according to the control information (36) with respect to the data resource corresponding to the received update notification.
A data update commit processing method characterized in that it is configured to request b).