JP2776274B2 - Virtual buffer control system in relay computer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission control method in a relay computer, and more particularly to a virtual buffer control system in a relay computer.

[0002]

2. Description of the Related Art Referring to FIG.
1 is an application program 52 for exchanging messages between host computers or between a host computer and a terminal.
And a plurality of transmission buffers 53, and are connected to a host computer (not shown) by a host line 54 and to other host computers or terminals by a plurality of external lines 55.

[0003] Referring to FIG. 6, upon receiving a message (DT1) from the host line 54, the conventional relay computer 51 acknowledges the receipt of the message (DT1) (hereinafter, referred to as "DT1").
ACK), the application program 52 performs arbitrary processing on the message (DT1), stores the processing result in the transmission buffer 53, and transmits the processing result to the external line 55.

[0004] This conventional relay computer 51 has an external line 5
5, the transmission buffer 53 is not released until a response to the processing result is received, and further, a response of the processing result is not transmitted to the host line 54 until the response is received.

Further, the host computer does not transmit the next message until a response to the processing result is received.

[0006]

In the above-described conventional technique, the transmission and reception of messages between the host computer, the relay computer, and the external line are all performed sequentially. Therefore, as shown in FIG. If the relay computer 51 fails after transmitting the processing result to the external line 55, the relay computer 51 cannot receive a response to the processing result from the external line 55, and further sends the processing result to the host line 54. Cannot be transmitted, the host computer retransmits the message (DT1), receives the message (DT1) from the host line 54, executes the application program 52, and transmits the message to the external line 55. There is a problem that the processing must be executed again.

An object of the present invention is to improve the throughput of message data transmission / reception processing via a relay computer.

Another object of the present invention is to resume transmission / reception processing of a message without the need to retransmit a message from the host computer or re-execute an application program in the relay computer even if a failure occurs in the relay computer. Is to be able to do that.

[0009]

Means for Solving the Problems A virtual buffer control system in a first relay computer according to the present invention comprises: a relay computer for exchanging messages between at least one host computer and at least one between a host computer and a terminal; A host line connecting a computer and a host computer, at least one external line connecting the relay computer to another host computer or terminal, and an external storage device for storing a telegram; and the relay computer In response to receiving the message from the host line, transmitting an acknowledgment to the host line, performing a predetermined process based on the received message,
The message of the processing result is stored in the external storage device, and if there is the available external line, the message of the processing result is read out from the external storage device and transmitted to the external line, and from the external line, When a positive response to the transmission of the processing result message is received, a response pseudo message is transmitted to the host line, and when a response to the processing result message is received from the external line, It sends a response message to the line, to remove the message of the external storage device stored the processing result, whereas, before
The message of the processing result in the relay computer is sent to the external
After transmission to the line and from the external line to the transmission
If you fail before you receive an acknowledgment,
After restart and when there is an available external line
Read the message of the processing result from the external storage device
And transmitting to the external line .

[0010]

A virtual buffer control system in a second relay computer according to the present invention includes a relay computer for exchanging messages between host computers and / or at least one of a host computer and a terminal; and a relay computer and a host computer. A host line to be connected, at least one external line connecting the relay computer and another host computer or terminal, and an external storage device including at least one virtual buffer for storing a telegram, wherein the relay computer comprises: An application program that performs exchange processing based on the message received from the host line, a virtual buffer control unit that secures an empty virtual buffer on the external storage device and stores a processing result of the application program, A main note that exists for each external line and stores a message to be transmitted to the external line. At least one transmission buffer on the storage device, in response to receiving a message from the host line, transmitting an acknowledgment to the host line, and based on the received message, the application program To perform a predetermined process, and store the telegram of the processing result in the virtual buffer by the virtual buffer control unit. If there is a free external line, the telegram of the processing result stored in the virtual buffer is output. Copying the data to the transmission buffer corresponding to the external line, transmitting the copied data to the external line, and, when receiving an acknowledgment for transmission of the processing result message from the external line, a response pseudo message to the host line. And transmitting a response message to the host line when a response to the message of the processing result is received from the external line. The features.

[0012] A virtual buffer control system in a third relay computer according to the present invention is the virtual buffer control system in the second relay computer, wherein the number of the virtual buffers is at least the number of the transmission buffers. .

A virtual buffer control system in a fourth relay computer according to the present invention is the virtual buffer control system in the second and third relay computers, wherein the relay computer has a processing result of the application program stored in the transmission buffer. After transmitting to the external line and before receiving an acknowledgment for the transmission from the external line, if itself fails, after a restart and when the external line is available, the virtual The processing result of the application program is read from the virtual buffer by a buffer control unit, copied to the transmission buffer, and then transmitted to the external line.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings.

Referring to FIG. 1, a virtual buffer control system in a relay computer according to an embodiment of the present invention includes a relay computer 11 for exchanging a message between host computers or between a host computer and a terminal, Application program 12 in relay computer 11 that performs exchange processing
And a transmission buffer 13 in the relay computer 11 for storing a transmission message, a host line 14 connecting the host computer to the relay computer 11, and connecting the relay computer 11 to another host computer or another terminal. And a virtual buffer control unit 16 in the relay computer 11 for storing a telegram of the processing result of the application program 12 in a virtual buffer 18 in the external storage device 17.

It is assumed that a plurality of external lines 15 and transmission buffers 13 are set and correspond to one-to-one.

It is assumed that the number of virtual buffers 18 equal to or larger than the number of transmission buffers 13 is set in the external storage device 17 in advance.

Next, a virtual buffer control system in a relay computer according to an embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG.

FIG. 2 shows the connection to the host line 14 and the relay computer 1.
1 and the procedure of transmission and reception of message data between the external line 15 are shown in chronological order.

When the relay computer 11 receives the message (DT1) from the host line 14 (step 111), the relay computer 11 returns an acknowledgment (hereinafter referred to as ACK) to the host line 14 for receiving the message (DT1) (step 111). Step 112)
At the same time, the application program 12 is executed based on the received message (DT1) (step 113).

The relay computer 11 processes the message (DT1) by the application program 12 (hereinafter referred to as the "DT1").
The processing result is sent to the virtual buffer control unit 16.
Thus, the data is stored in the virtual buffer 18 in the external storage device 17 (step 114).

The virtual buffer control means 16 executes step 1
At 14, an empty virtual buffer 18 is searched and secured in the external storage device 17, and a telegram of the processing result is stored. However, the process of allocating an empty virtual buffer 18 may employ a method of dynamically generating the virtual buffer 18 when storing a message as a processing result.

If there is a free external line 15, the relay computer 11 copies the telegram of the processing result stored in the virtual buffer 18 to the transmission buffer 13 corresponding to the external line 15 (step 115). 15 (step 116).

The relay computer 11 receives an ACK for the transmission of the processing result message from the external line 15 (step 1).
17) and the transmission buffer 13 corresponding to the external line 15
Is released (step 118), and a response pseudo message of the processing result is transmitted to the host line 14 (step 119).

When the relay computer 11 receives a response message corresponding to the processing result message transmitted in step 116 from the external line 15 (step 11A), the virtual buffer control means 16 causes the processing result corresponding to the response message to be transmitted. The virtual buffer 18 storing the message is released (step 11B), and the response message of the processing result is transmitted to the host line 14 (step 11C).

The host computer (not shown) receives the response pseudo message of the processing result from the host line 14, and if there is a message to be transmitted (for example, DT2), the host computer 14
Send to

When receiving the message (DT2) from the host line 14, the relay computer 11 executes steps 111 to 11C for the message (DT2).

After the host computer (not shown) receives the response message of the processing result from the host line 14, if there is a message to be transmitted (for example, DT3), it transmits the message to the host line 14.

Similarly, when the relay computer 11 receives the message (DT3) from the host line 14, the relay computer 11
Steps 111 to 11C are executed for 3).

FIG. 3 shows, in chronological order, a procedure of transmitting and receiving a message between the host line 14, the relay computer 11, and the external line 15 when a failure occurs in the relay computer 11.

The relay computer 11 receives the message (DT1) from the host line 14, and executes steps 111 to 1
After executing step 16, if a failure occurs, step 117
Cannot receive the ACK for the message transmission of the processing result from the external line 15 in.

The restarted relay computer 11 reads the processing result message from the virtual buffer 18 in which the processing result message is stored by the virtual buffer control means 16 (step 11D), and the free external line 15 If there is, the message of the processing result is copied to the transmission buffer 13 corresponding to the external line 15 (step 11E), and
The data is transmitted to the external line 15 (step 11F).

Similarly, the relay computer 11 proceeds to step 1
Steps 17 to 11C are executed.

With the above, the processing of the virtual buffer control system in the relay computer according to one embodiment of the present invention is completed.

The virtual buffer control system in the relay computer according to one embodiment of the present invention requires retransmission of a message from the host computer and re-execution of the application program in the relay computer even if a failure occurs in the relay computer. Instead, there is an effect that the transmission / reception processing of the message can be restarted.

[0036]

As described above, the virtual buffer control system in the relay computer according to the present invention is capable of retransmitting a message from the host computer,
The relay computer does not need to re-execute the application program in the relay computer, and has the effect of restarting the transmission / reception processing of the message.The relay computer transmits the message of the processing result of the application program to the external line, and When an ACK for transmission is received, a pseudo-response message is transmitted to the host line to urge the host computer to transmit the next message, thereby increasing the throughput of the message transmission / reception process via the relay computer. This has the effect of being able to be improved.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing an example of a host line 14 according to an embodiment of the present invention;
It is a figure which shows the procedure of transmission / reception of the telegram between the relay computer 11 and the external line 15 in time series.

FIG. 3 is a diagram showing an example in which a failure occurs in the relay computer 11 according to the embodiment of the present invention;
FIG. 1 is a diagram showing, in chronological order, a procedure for transmitting and receiving a message between the external line 15 and the external line 15.

FIG. 4 is a flowchart showing a process of the relay computer 11 in one embodiment of the present invention.

FIG. 5 is a block diagram showing a conventional technique.

FIG. 6 is a diagram showing, in chronological order, a procedure for transmitting and receiving a message between a host line 54, a relay computer 51, and an external line 55 in the conventional technique.

FIG. 7 is a diagram showing, in chronological order, a procedure of transmission and reception of a message between the host line, the relay computer 51, and the external line 55 when a failure occurs in the relay computer 51 in the related art.

[Explanation of symbols]

 Reference Signs List 11 relay computer 12 application program 13 transmission buffer 14 host line 15 external line 16 virtual buffer control means 17 external storage device 18 virtual buffer 51 relay computer 52 application program 53 transmission buffer 54 host line 55 external line

Claims (1)

(57) [Claims] A relay computer for exchanging messages between at least one of the host computers and / or between the host computer and the terminal; a host line connecting the relay computer and the host computer; At least one external line for connecting a host computer or a terminal, and an external storage device for storing a telegram, wherein the relay computer responds to the reception of the telegram from the host line, Sends an acknowledgment, performs predetermined processing based on the received telegram, stores the telegram of the processing result in the external storage device, and if there is an available external line, transmits the telegram of the processing result. When reading from the external storage device and transmitting to the external line and receiving an acknowledgment for the transmission of the processing result message from the external line, the host A response pseudo message is transmitted to the line, and further, when a response to the message of the processing result is received from the external line, a response message is transmitted to the host line and stored in the external storage device. The message of the processing result is deleted , while the message in the relay computer is deleted.
After and before sending the message of the processing result to the external line
Before receiving an acknowledgment for the transmission from the external line
In the event of a failure in the
When the external line is available, the external storage device
A virtual buffer control system in the relay computer , which reads out the telegram of the processing result from the network and transmits the telegram to the external line .