JP7608760B2 - Transaction control device, transaction control method, and program - Google Patents

Description

This disclosure relates to transaction control.

To shorten the processing time of a computer, multiple processes are executed in parallel. Patent Document 1 discloses a data parallel processing system that generates multiple threads and executes multiple transaction processes in parallel. The data parallel processing system of Patent Document 1 prevents overtaking of completions by controlling waiting to see whether the transaction being processed by each thread can be completed (file output).

JP 2014-211782 A

In the system disclosed in Patent Document 1, a thread that processes a subsequent transaction must wait for the completion of the preceding transaction before completing its processing. However, for example, in processing such as converting video or audio data, the data processing volume for each fixed processing unit (time, etc.) varies due to the characteristics of the data. For example, even if processing is divided into processing units of 10 seconds each, differences in processing time may occur because the contents are different between one section and another. In this way, when there is a large variation in processing time for each transaction, the degree of parallelism decreases as the thread that processes the later transaction waits for the transaction with the long processing time to complete. This poses the issue of reduced throughput.

One of the objectives of the present disclosure is to provide a transaction control device or the like that suppresses a decrease in throughput in parallel processing of transactions that must be completed in the order in which they are received.

The transaction control device according to the present disclosure includes a task allocation means for assigning tasks to transactions, each of which includes processes executed in the order of a first process and a second process, in the order in which the transactions are received, and a transaction processing means for processing the transactions by executing the tasks assigned to the transactions, and when the first process of a later-accepted transaction is terminated before the earlier-accepted transaction is terminated, the transaction processing means cancels the task allocation to the later-accepted transaction, and when the transaction is terminated, if the transaction received next after the terminated transaction has no task assigned to it, assigns the task assigned to the previously-accepted transaction to the next-accepted transaction.

The transaction control method according to the present disclosure accepts a transaction including processes that are executed in the order of a first process and a second process, assigns tasks in the order in which the transactions are received, processes the transactions by executing the tasks assigned to the transactions, and if the first process of the later-accepted transaction is completed before the earlier-accepted transaction is completed, the task assignment to the transaction is released, and if the transaction accepted next to the first transaction has no task assigned when the transaction is completed, the task assigned to the completed transaction is assigned to the next-accepted transaction.

The program disclosed herein causes a computer to execute the steps of accepting a transaction including processes executed in the order of a first process and a second process, allocating tasks in the order in which the transactions are accepted, processing the transactions by executing the tasks assigned to the transactions, unassigning the task to a transaction if the first process of the later accepted transaction is completed before the earlier accepted transaction is completed, and, if the transaction accepted next to the earlier accepted transaction has no task assigned when the earlier accepted transaction is completed, assigning the task assigned to the completed transaction to the next accepted transaction.

According to the present disclosure, it is possible to suppress a decrease in throughput in parallel processing of transactions that must be completed in the order in which they are received.

FIG. 2 is a block diagram illustrating a configuration of a transaction control device 102 according to the first embodiment. FIG. 1 is a diagram illustrating an example of a system to which a transaction control device 102 is applied. FIG. 13 illustrates an example of a state in which a transaction has been accepted. 10 is a flowchart illustrating an example of an allocation process in the transaction control device 102. FIG. 13 is a diagram illustrating an example of a state in which all tasks are assigned to a transaction. 4 is a flowchart illustrating an example of a task control process in the transaction controller 102. FIG. 5 is a diagram showing a state subsequent to the state shown in FIG. 4 . FIG. 7 is a diagram showing a state subsequent to the state shown in FIG. 6; FIG. 8 is a diagram showing a state subsequent to the state shown in FIG. 7; FIG. 9 is a diagram showing a state subsequent to the state shown in FIG. 8 . FIG. 13 illustrates an example of a state in which a transaction including group information has been accepted. FIG. 13 is a diagram illustrating an example of a state in which tasks are assigned to each group. FIG. 13 is a block diagram illustrating a configuration of a transaction control device 102 according to a third embodiment. 13 is a flowchart illustrating an example of an operation of a transaction control device 102 according to the third embodiment. FIG. 5 is a block diagram showing an example of the hardware configuration of a computer 500.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
[First embodiment]
[composition]
Fig. 1A is a block diagram illustrating an example of the configuration of a transaction control device 102 according to the first embodiment. The transaction control device 102 includes a transaction reception management unit 104, a task allocation unit 105, a waiting task management unit 106, and a transaction processing unit 107. Fig. 1B is a diagram illustrating an example of a system to which the transaction control device 102 is applied. The transaction control device 102 is connected to a processing request device 101 on which an application is executed, and a storage device 103 on which a processing result is stored.

The transaction reception management unit 104 receives and manages application processing requests as transactions from one or more processing request devices 101.

A transaction consists of a specified process on data (hereinafter referred to as data processing) and a completion process performed on the results of the data processing. The data processing may be a specified calculation process on the data specified in the transaction. The completion process may be a process of outputting (storing) the results of the data processing to one or more storage devices 103.

The data processing is an embodiment of the first processing in this disclosure, and the completion processing is an embodiment of the second processing in this disclosure.

If the transaction is a database transaction, the data processing may be processing of a specified command on data specified in the transaction. In this case, the completion processing may be a commit process that outputs (stores) and confirms the results of the data processing.

In this disclosure, a transaction is processed by a task assigned to that transaction. Here, a task represents a unit of processing, and at a given moment, one task can process one transaction. In other words, one task cannot process multiple transactions simultaneously. There can be one or more tasks in a device, and the number can be determined arbitrarily by the system user, etc., based on the system's purpose and resources (number of CPU (Central Processing Unit) cores, etc.).

The transaction reception management unit 104 manages transactions in the order in which they are received. For example, the transaction reception management unit 104 manages transactions in a queue. For example, the transaction reception management unit 104 may include a queue that stores transaction identifiers in the order in which the transactions are received.

The waiting task management unit 106 manages tasks that are not assigned to a transaction. The waiting task management unit 106 may manage tasks in a stack, a queue, or in the order of task identification numbers.

The task allocation unit 105 assigns the waiting task managed by the waiting task management unit 106 to the first transaction in the queue of the transaction reception management unit 104, and passes it to the transaction processing unit 107.

In the transaction processing unit 107, a task processes a transaction and outputs the processing result to the storage device 103. In the transaction processing unit 107, multiple tasks may run simultaneously. That is, the transaction processing unit 107 can process multiple transactions in parallel. However, the processing results are output in the order in which the transaction control device 102 accepts the transactions. The transaction processing unit 107 may include a queue that stores the identifiers of the transactions in the order in which they are handed over.

[Action]
The operation of the transaction control device according to the first embodiment will be described with reference to FIGS.

Figure 2 is a diagram showing an example of the state in which the transaction reception management unit 104 has received a transaction. In Figure 2, the transactions are managed in a queue in the order in which they are received. The arrows in the transaction reception management unit 104 indicate the queues.

In FIG. 2, as an example, there are four tasks, none of which are assigned to a transaction, and the transaction is waiting for a task to be assigned to it. The arrows in the task waiting for assignment management unit 106 indicate queues.

Figure 3 is a flowchart showing an example of the allocation process of the task allocation unit 105. First, the task allocation unit 105 takes out one transaction at the top of the queue in the transaction reception management unit 104 ("transaction Tx A" in Figure 2) and one task at the top of the queue in the task waiting for allocation management unit 106 ("task 1" in Figure 2). Next, the task allocation unit 105 assigns the taken out task to a transaction and passes it to the transaction processing unit 107. This is repeated until either the queue of transactions in the transaction reception management unit 104 or the queue of tasks in the task waiting for allocation management unit 106 becomes empty (steps S01 to S05).

Figure 4 shows the state in Figure 2 where all tasks have been assigned to transactions by the task allocation unit 105 and handed over to the transaction processing unit 107. Within the transaction processing unit 107, task and transaction pairs 203A to 203D are managed in a queue in the order in which the transactions were received, i.e., in the order in which they were handed over from the task allocation unit 105. In Figure 4, the arrows within the transaction processing unit 107 indicate queues. Note that in Figure 4, transaction Tx E in the transaction reception management unit 104 is waiting to be processed without being assigned a task.

Figure 5 is a flowchart showing an example of task control processing of the transaction control device 102 after a task is handed over to the transaction processing unit 107.

The transaction processing unit 107 executes each task and performs data processing of the transaction (step E01). For example, the transaction processing unit 107 processes transactions Tx A, Tx B, Tx C, and Tx D by executing tasks 1, 2, 3, and 4.

When data processing of a transaction is completed, each task suspends processing of the transaction and waits. Each task may notify the transaction processing unit 107 of the completion of data processing. When the transaction processing unit 107 detects the completion of data processing in a task, it determines whether the transaction to which the task is assigned is at the top of the queue.

If the transaction is not at the top of the queue ("No" in step E02), the preceding transaction has not been completed and therefore completion processing is not performed. In this case, the transaction processing unit 107 releases the task from the transaction (step E08). The task waiting for assignment management unit 106 re-registers the released task in the queue within the task waiting for assignment management unit 106 (step E09).

Figure 6 shows a state in which, after the state in Figure 4, data processing of transaction Tx B processed by task 2 is completed before the completion processing of the preceding transaction Tx A processed by task 1 is completed. In Figure 6, task 2 is released from the allocation of transaction Tx B and registered in the queue of the task waiting for allocation management unit 106. After that, by the operation of the task allocation unit 105 (Figure 3), task 2 is assigned to transaction Tx E waiting in the transaction reception management unit 104. After being handed over to the transaction processing unit 107, the transaction processing unit 107 processes transaction Tx E by executing task 2. Figure 7 shows a state in which, after the state in Figure 6, task 2 is assigned to transaction Tx E and task 1 has completed data processing.

Returning to the explanation of FIG. 5, if the transaction is at the top of the queue (Yes in step E02), the transaction processing unit 107 resumes execution of the task assigned to the transaction and completes the transaction (step E03). When the completion process is complete, the transaction processing unit 107 deletes the transaction from the queue (step E04). If another transaction remains in the queue (Yes in step E05) and no task has been assigned to the new top transaction in the queue (No in step E06), the transaction processing unit 107 reassigns the task that was assigned to the transaction whose completion process has been completed to the top transaction (step E07).

If another transaction remains in the queue of the transaction processing unit 107 ("Yes" in step E05) and a task has been assigned to the new top transaction in the queue ("Yes" in step E06), the waiting task management unit 106 registers the task that was assigned to the transaction whose completion processing has been completed in the queue as a waiting task (step E10).

Figure 8 shows the state after the state of Figure 7, in which task 1, which was assigned to transaction Tx A whose completion processing has been completed, is reallocated to transaction Tx B (after step E07). In Figure 8, transaction Tx B has completed processing up to data processing, and is at the top of the queue. Therefore, the transaction processing unit 107 executes task 1 to complete the transaction (step E03). When the completion processing of transaction Tx B is completed, the transaction is deleted from the queue (step E04).

When transaction Tx C, which is the new head of the queue, is confirmed ("Yes" in step E05), task 3 has been assigned to it ("Yes" in step E06), so the task waiting for assignment management unit 106 re-registers task 1 in the queue (step E10). Figure 9 shows the state after the state in Figure 8 where transaction Tx B, whose completion processing has been completed, is deleted from the queue of the transaction processing unit 107 and task 1 is re-registered as a task waiting for assignment.

[effect]
According to the first embodiment, it is possible to suppress a decrease in throughput in parallel processing of transactions that need to be completed in the order in which they are received.

The reason for this is that if data processing of a later accepted transaction is completed before the earlier accepted transaction is completed, the transaction processing unit 107 releases the task allocation to the later transaction. Also, the task allocation unit 105 allocates the release task to a new transaction. Furthermore, if a task has not been assigned to the transaction accepted after the completed transaction, the transaction processing unit 107 allocates the task that was assigned to the completed transaction to the next accepted transaction.

[Second embodiment]
In the first embodiment, an example was described in which the order of transaction completion is guaranteed to be the order of transaction acceptance. In the second embodiment, a case in which transactions that do not need to follow the order of completion are mixed will be described. Also, a case in which multiple ranges (groups) are provided in which the order of transaction completion is guaranteed will be described. Note that there may be only one group in which the order of transaction completion is guaranteed.

In the second embodiment, the description of the configuration and operation similar to those of the first embodiment may be omitted.

[composition]
In the second embodiment, some or all of a transaction belongs to a group. The transaction reception/management unit 104 receives a transaction including group information indicating which group the transaction belongs to. The group information is assigned by an application based on an arbitrary rule, for example.

As in the first embodiment, the task allocation unit 105 assigns a task to a transaction and passes it to the transaction processing unit 107. The transaction processing unit 107 reads the group information of the transaction and provides a queue for each group. Then, the transaction processing unit 107 processes the transaction by controlling the task for each group in the same way as in the first embodiment. Note that the transaction processing unit 107 does not need to manage transactions that do not belong to a group in a queue.

The transaction processing unit 107 may output the transaction processing results to a different storage device 103 for each group. The storage device 103 may store the transaction processing results in a different file for each group.

Figure 10 shows an example of a state in which transactions including group information have been accepted. In Figure 10, transactions Tx A and Tx C include group information indicating that they belong to group α. Transaction Tx B does not include group information. Transaction Tx D includes group information indicating that it belongs to group β.

Figure 11 is a diagram showing an example of a state in which a queue is provided for each group after the state of Figure 10. In Figure 11, the completion order of transactions Tx A and Tx C is controlled in group α, and the completion order of transaction Tx D is controlled in group β. Furthermore, the completion order of transaction Tx B is not controlled. When a transaction belongs to a group, for example, the process shown in Figure 5 is performed for each queue of the group.

Specifically, if data processing of a transaction that belongs to the same group and is accepted later is completed before the previously accepted transaction is completed, the transaction processing unit 107 releases the task assignment to the later accepted transaction. When a transaction is completed, if a task is not assigned to a transaction that belongs to the same group as the completed transaction and is accepted after the completed transaction, the transaction processing unit 107 assigns the task assigned to the completed transaction to the next accepted transaction. This controls the order in which transactions within a group are completed.

If a transaction does not belong to a group, the transaction processing unit 107 does not release the task allocation until the transaction is completed. That is, for example, after completing data processing of a transaction that does not belong to a group, the transaction processing unit 107 continues to perform completion processing regardless of whether other transactions have been completed.

[effect]
According to the second embodiment, in parallel transaction processing, even when transactions are terminated for each group in the order in which they were received, it is possible to suppress a decrease in throughput. This is because the transaction processing unit 107 manages the queue based on the group information of the transaction. Also, according to the second embodiment, it is possible to suppress a decrease in throughput even when processes that do not need to maintain the order of transaction termination are mixed.

[Third embodiment]
Another embodiment of the present disclosure will be described. Fig. 12 is a block diagram illustrating a configuration of a transaction control device 102 according to a third embodiment. In the third embodiment, the transaction control device 102 includes a task allocation unit 105 and a transaction processing unit 107. Regarding the configuration similar to the configuration of the first embodiment, the description of the third embodiment will be omitted.

In the third embodiment, the task allocation unit 105 accepts a processing request from an application of an external device (not shown) as a transaction. The transaction includes a first process and a second process that are executed in that order. The transaction processing unit 107 processes the transactions in the order in which they are received. The transaction processing unit 107 executes multiple tasks in parallel and processes the transactions in parallel.

[Action]
13 is a flowchart showing an example of the operation of the transaction control device 102 according to the third embodiment. The task allocation unit 105 receives a transaction (step S101). The task allocation unit 105 assigns tasks to the transactions in the order in which the transactions were received (step S102). The transaction processing unit 107 executes the assigned tasks and performs a first process of the transaction (step S103).

If the first processing of the later accepted transaction is completed before the earlier accepted transaction is completed (step S104: No), the transaction processing unit 107 releases the task from the transaction whose first processing has been completed (step S105). The released task is assigned to a new transaction in step S102.

When the first process is completed, if the previously accepted transaction has been completed ("Yes" in step S104), the transaction processing unit 107 continues to execute the assigned process and performs the second process (step S106).

When the second process ends and the transaction ends, if a task has been assigned to the next transaction of the completed transaction ("Yes" in step S107), the transaction processing unit 107 puts the task that has completed the transaction on hold. The task put on hold is assigned to a new transaction in step S102.

If no task has been assigned to the transaction following the completed transaction ("No" in step S107), the transaction processing unit 107 assigns the task that was assigned to the completed transaction to the next transaction (step S108).

The transaction processing unit 107 executes the reallocated task and performs the second processing of the transaction (step S106).

[effect]
According to the third embodiment, it is possible to suppress a decrease in throughput in parallel processing of transactions that need to be completed in the order in which they are received.

The reason for this is that if the first processing of a later accepted transaction is completed before the earlier accepted transaction is completed, the transaction processing unit 107 cancels the task allocation to the later transaction. Also, if a task is not assigned to the transaction accepted next to the completed transaction, the transaction processing unit 107 assigns the task assigned to the completed transaction to the next accepted transaction.

[Application example]
Each of the above-described embodiments can be applied to a system for processing a large amount of information in a short period of time, such as batch processing.

[Hardware configuration]
In each of the above-described embodiments, each component of the transaction control device 102 is shown as a functional block. Some or all of the components of each device may be realized by any combination of the computer 500 and a program.

FIG. 14 is a block diagram showing an example of the hardware configuration of a computer 500. Referring to FIG. 14, the computer 500 includes, for example, a CPU (Central Processing Unit) 501, a ROM (Read Only Memory) 502, a RAM (Random Access Memory) 503, a program 504, a storage device 505, a drive device 507, a communication interface 508, an input device 509, an input/output interface 511, and a bus 512.

The program 504 includes instructions for implementing each function of each device. The program 504 is stored in advance in the ROM 502, the RAM 503, or the storage device 505. The CPU 501 implements each function of the transaction control device 102 by executing the instructions included in the program 504. For example, the CPU 501 implements each function of the transaction control device 102 by executing the instructions included in the program 504. The RAM 503 may also store data to be processed in each function.

The drive device 507 reads and writes data from the recording medium 506. The communication interface 508 provides an interface with the communication network. The input device 509 is, for example, a mouse or keyboard, and accepts information input from system users, etc. The output device 510 is, for example, a display, and outputs (displays) information to the system user. The input/output interface 511 provides an interface with peripheral devices. The bus 512 connects these hardware components. The program 504 may be supplied to the CPU 501 via the communication network, or may be stored in advance on the recording medium 506, read by the drive device 507, and supplied to the CPU 501.

Note that the hardware configuration shown in FIG. 14 is an example, and other components may be added, or some components may not be included.

There are various variations in the way the transaction control device 102 is realized. For example, each component of the transaction control device 102 may be realized by any combination of a different computer and program. In addition, multiple components of the transaction control device 102 may be realized by any combination of a single computer and program.

Furthermore, some or all of the components may be realized by general-purpose or dedicated circuits including a processor, etc., or a combination of these. These circuits may be configured by a single chip, or may be configured by multiple chips connected via a bus. Some or all of the components may be realized by a combination of the above-mentioned circuits, etc., and a program.

In addition, when some or all of the components are realized by multiple computers, circuits, etc., the multiple computers, circuits, etc. may be centralized or distributed.

Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above embodiments. Various modifications that can be understood by a person skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, the configurations in each embodiment can be combined with each other without departing from the scope of the present disclosure.

101 Processing request device 102 Transaction control device 103 Storage device 104 Transaction reception management unit 105 Task allocation unit 106 Task waiting for allocation management unit 107 Transaction processing unit

Claims (8)

a task allocation means for allocating tasks to transactions including processes to be executed in the order of data processing and commit processing in the order in which the transactions are received;
a transaction processing means for processing the transaction by executing a task assigned to the transaction;
Equipped with
The transaction processing means includes:
When data processing of the later accepted transaction is completed before the earlier accepted transaction is completed, the task allocation to the later accepted transaction is cancelled;
When the transaction is terminated, if a task is not assigned to the commit process of the transaction accepted next to the terminated transaction, the transaction control device assigns the task assigned to the terminated transaction to the next accepted transaction. The transaction processing means includes:
a queue for storing identifiers of transactions to be processed in the order in which the transactions are received;
when data processing of the transaction is completed and the transaction whose data processing has been completed is not at the head of the queue, release the task assignment to the transaction whose data processing has been completed;
2. The transaction control device according to claim 1, wherein, when the transaction is completed, if there is a transaction at the head of the queue that has not been assigned a task, the task that was assigned to the completed transaction is assigned to the transaction at the head of the queue. The system further includes a waiting task management unit for managing the tasks waiting for allocation,
the task allocation means allocates the waiting task to the accepted transaction;
the waiting task management means, when a task is not assigned to a transaction accepted next to the completed transaction, manages the task assigned to the completed transaction as the waiting task.
The transaction control device according to claim 1 or 2. The transactions include transactions belonging to a group;
The transaction processing means includes:
When data processing of a transaction that belongs to the same group and is accepted later is completed before the previously accepted transaction is completed, the task allocation to the subsequently accepted transaction is released;
when the transaction is terminated, if a task is not assigned to the transaction that belongs to the same group as the terminated transaction and is accepted next after the terminated transaction, assigning the task that was assigned to the terminated transaction to the next accepted transaction;
The transaction control device according to any one of claims 1 to 3. the transaction processing means does not release the task allocation for a transaction not belonging to the group until the transaction is completed;
The transaction control device according to claim 4. the transaction processing means includes a queue for storing identifiers of transactions to be processed in the order of receipt of the transactions for each group to which the transactions belong;
The transaction control device according to claim 4. Accepts transactions that contain operations that are executed in the order of data processing and commit processing,
Assigning tasks to the transactions in the order in which they are received;
Processing the transaction by performing tasks assigned to the transaction;
If data processing of the later accepted transaction is completed before the earlier accepted transaction is completed, the task allocation to the transaction is cancelled;
when the transaction is terminated, if no task is assigned to a commit process of a transaction accepted next to the terminated transaction, assigning the task assigned to the terminated transaction to the next accepted transaction;
Transaction control method. accepting a transaction including operations that are executed in the order of a data operation and a commit operation;
assigning tasks to the transactions in the order in which they are received;
processing said transaction by executing a task assigned to said transaction;
a step of canceling the task allocation to a transaction when data processing of a later accepted transaction is completed before the earlier accepted transaction is completed;
a step of allocating the task assigned to the completed transaction to a next accepted transaction when no task has been assigned to a commit process of the next accepted transaction when the completed transaction is terminated;
A program that causes a computer to execute the following.

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