JPH04123162A - Inter-process communication control system - Google Patents

Abstract

PURPOSE:To curtail the number of times of a message transfer by transferring directly a message transmitted by a transmitting person to a receiving person from the transmitting person. CONSTITUTION:A transmitting person 3 transfers a position confirmation message 101 for confirming a position of a receiving person 4 to a designated transfer destination. When the position confirmation message 101 is received, the receiving person 4 transfers a position notice message 103 for reporting a position of the receiving person 4 to a generating person 9 of the position confirmation message. When the position notice message 103 is received, the transmitting person 3 retransfers a held message 110 to the receiving person 4. Subsequently, when the designation of a retransfer destination is received, a mediator 8 transfers a position confirmation message 102 for confirming a position of the receiving person 4, holds continuously the position confirmation message 101 at the time when the position of the receiving person 4 is unknown, when the position confirmation message is received, and retransfers the held message 110 to the receiving person 4, when the position notice message 103 is received. In such a way, the message can be transferred by a small number of times of a transfer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control method for interprocess communication functions in a parallel and distributed processing system.

[Prior Art] When sending certain data to a certain process through communication, it is assumed that the source process does not know how to send the data to this process. If there is a third process that knows how to send data to the destination process, and the source process also knows how to send data to this process, then the source process Data can be sent to process No. 3 to request transfer.

In other words, even if process A cannot send data to process Z, it can send data to process B.
If process A can send data to process Z, then process A can send data to process B.
and data can be transferred between the two.

Not limited to the above-mentioned example, it is possible to consider a type of communication in which many processes that mediate, such as process B, are involved.

For example, in the above example, instead of sending data from process B to Z, it is sent via processes C2D,...,Y,
Communication from process A to Z can also be performed by sending it to process Z.

The advantage of this communication is that the sender does not necessarily need to know the destination of the data, which increases the independence of each functional unit that makes up the computer system, making the design, construction, and maintenance of the entire system easier. have.

By the way, as a control method for realizing the above-mentioned communication function, first, there is a method of passing data to all processes related to communication.

Furthermore, an operation called dereference is also performed to seek the most cutting edge possible by tracing the chain of intermediaries. In the previous example, process A asks process B for a means of sending to process C, and then, using the means of sending obtained thereby, asks process C for a means of sending to process D, and so on, following the chain, It refers to obtaining a means of transmission to a later process. By using the transmission means obtained in this way, the sender of data can directly transmit data to the preceding process, thereby omitting the chain of intermediaries and reducing the number of data transfers.

However, the chain is not necessarily complete when it is traced. In other words, when you ask an intermediary how to send data to a destination process, the process may not have been decided yet, or even if the destination has been decided, it may not have the means to send data. sell. in this case,
Stop searching the chain and transfer the data to this process. Then, once this process is given the means to send to the destination, it will continue the transfer.

On a computer system with only one memory, communication processing does not take much time even if the conventional control method described above is used. This is because, in such a computer system, the processing time required for data transfer is small and constant regardless of the amount of data transferred. Also, in dereferencing, it is possible to ask the male process about the transmission means with little effort.

[Problem to be solved by the invention]

However, conventional control methods are not suitable for systems that require a large amount of time to transfer data. For example, in a computer system consisting of multiple processors and memory attached to each processor that cannot be directly read or written by other processors, the processing time required to transfer data between memories is large, and the amount of data transferred is large. is proportional to. Therefore, applying the conventional control method to this system requires a very large amount of processing time.

In order to shorten this processing time, it is necessary to reduce the number of data transfers. However, in the computer system configured as described above, dereferencing is not very effective as a means of reducing the number of data transfers.

This is because, in the computer system having the above-described configuration, when attempting to inquire about the transmission means for dereference, data transfer between memories becomes necessary several times.

Furthermore, the number of data transfers that can be reduced by dereferencing varies greatly depending on the order in which each process is given a means of transmitting data to a destination. It is not rare that it cannot be reduced at all. For example, when trying to communicate from process A to C via process B, if the means of transmission between processes B and C is provided before the means of transmission between processes A and B, then process A will communicate with process C via process B. The method for sending data to process B can be found by inquiring process B, and data transfer only needs to be done once from process A to process C.

However, the transmission means between processes A and B is
If it is given before the means of transmission between processes, process A will not be able to obtain the means of transmission to process C even if it tries to dereference, so the data will be transferred from A to B and from B to C.
This will be his second year at the school. This is the same number of times as when no dereference is performed.

An object of the present invention is to provide an interprocess communication control method that eliminates such drawbacks and enables message transfer with a small number of transfers.

[Means to solve the problem]

In the present invention, a sender generates and forwards a message, an intermediary receives and retransmits a message sent by the sender or a message retransmitted by another intermediary, and a receiver receives the message. In an inter-process communication control method that receives messages and performs processing specified in the message, if the sender's location is unknown, the sender determines the receiver's location f before forwarding the generated message.
+I forwarding a first location confirmation message to a designated forwarding destination, and upon receiving the first location confirmation message, the receiver forwards a location notification message informing the receiver of the location. The sender, upon receiving the location notification message, retransmits the message it holds to the recipient who generated the location notification message, and the intermediary retransmits the message. Upon receiving the recipient's designation, the intermediary forwards a second location confirmation message for confirming the recipient's location to the retransfer destination, and upon receiving the first location confirmation message, the intermediary , when the location of the recipient is unknown, the intermediary continues to hold the location confirmation message, and upon receiving the location notification message, the intermediary transmits the held message to the recipient who generated the location notification message. It is characterized by transfer.

In the present invention described above, when the forwarding destination of a message generated by the sender is in a processor different from the processor where the sender is located, the sender creates a new intermediary in the processor where the sender is located. , it is preferable to designate the transfer destination as a re-transfer destination of this intermediary, and further transfer the message generated by the sender to the intermediary.

Further, in the present invention described above, the sender does not transfer the first location confirmation message and receive the location notification message when the recipient of the message generated by the sender can be determined. , the intermediary forwards the message generated by the sender to the forwarding destination, and the intermediary forwards the second location confirmation message ε if the specified redirection destination is recognized as the recipient. It is preferable to immediately transfer the held message to the retransfer destination without receiving the location notification message.

Furthermore, in the present invention described above, if the number of messages to be transferred is less than a certain number, the sender simply sends the message to the sender without transferring the first location confirmation message and receiving the location notification message. The intermediary forwards the message to the forwarding destination specified by the intermediary, and if it can be determined that the number of messages to be forwarded by the intermediary is less than a certain number, the intermediary forwards the second location confirmation message. It is preferable to immediately transfer the held message to the specified retransfer destination without waiting for the reception of the location notification message.

(Operation) In the first invention, there is provided a sender who generates and forwards a message, and a sender who receives and retransmits a message sent by the sender or a message retransmitted by another intermediary. The intermediary who performs the transfer and the receiver who receives the message and processes specified in the message follow the following a, b, c, d, e, and f, respectively.

C. When the recipient's location is unknown, the sender forwards a location confirmation message to the designated transfer destination to confirm the recipient's location before forwarding the generated message.

When recipient b receives the location confirmation message described in section a, it forwards a location notification message informing the location of the receiver to the generator of the location confirmation message.

When the sender C receives the location notification message described in section b, it retransmits the message it holds to the recipient who generated the location notification message.

When the d intermediary receives an instruction for a retransfer destination, it forwards a location confirmation message for confirming the location of the recipient to the above-mentioned retransfer destination.

When the e-mediator receives the location confirmation message described in section a, if the recipient's location is unknown, the e-mediator continues to hold the location confirmation message.

When the f intermediary receives the location notification message described in section b, it retransmits the message it holds to the recipient who generated the location notification message.

In the second invention, in addition to the first invention, the sender behaves according to the following g.

gThe sender must be able to forward the message he/she generated to
When the processor is located in a processor different from the processor where the caller is located, a new intermediary is created in the processor where the caller is located, the above-mentioned transfer destination is specified as the re-transfer destination of this intermediary, and the above-mentioned intermediary is Forward messages generated by the caller to the sender.

In the third invention, in addition to the first invention, the sender and the intermediary each behave in accordance with the following i.

h If the sender can determine that the recipient of the message generated by the sender is the recipient, the sender is at the location described in the first invention!
The message generated by the caller is immediately transferred to the above-mentioned transfer destination without transferring the confirmation message or receiving the location notification message.

If the specified retransfer destination can be determined to be the recipient, the i-intermediary immediately performs the above retransfer without forwarding the location confirmation message and receiving the location notification message described in the first invention. Forward the previously held messages.

In the fourth invention, in addition to the first invention, the sender and the intermediary behave in accordance with the following j and k, respectively.

j If the number of messages to be forwarded is less than a certain number, the sender immediately forwards the message to the designated forwarding destination without forwarding the location confirmation message and receiving the location notification message as described in the first invention. Forward the message you are trying to forward.

If the intermediary can determine that the number of messages to be transferred by this intermediary is less than or equal to a certain number, the intermediary does not transfer the W confirmation message as described in the first invention, and also transfers the confirmation message at the position described in the first invention. To immediately transfer a held message to a specified retransfer destination without waiting for reception of a notification message.

Here, for example, the number of data sent from the sender to the receiver is M, and the number of intermediaries through which the data passes is N.
Then, in the conventional control system, if dereferencing is not performed, the sender and all intermediaries transfer M pieces of data to the destination, so the total number of required data transfers is M(N+1).

On the other hand, according to the inter-process communication control method of the first invention,
The caller and all intermediaries send a total of N+1 location messages to the destination, and all intermediaries receive a total of N location messages received from callers or intermediaries that are directed to this intermediary. The receiver sends a total of N+1 location notification messages, one for every location confirmation message. Furthermore, since the sender sends M pieces of data to the receiver, the total number of data transfers is 3N+2
It is 10M. Therefore, according to the first invention, the condition for reducing the number of data transfers is 3 N+2 +M≦M(
N+1) becomes (M-3)N22. That is, when sending five or more pieces of data through one or more intermediaries, or when sending four or more pieces of data through two or more intermediaries, the first invention reduces the number of data transfers. be able to.

When dereferencing is performed, the number of data transfers depends on the processing execution status. In other words, the number of required data transfers changes depending on the order in which each process is provided with a means of transmitting to a destination.

When the number of data transfers is the smallest, the sender sends a message to all intermediaries inquiring about the transmission method, messages are sent in response to each of these inquiries, and based on this, the sender sends a message to all intermediaries asking about the transmission method. data is transferred to. Therefore, the total number of data transfers is 2
N+M.

This is the number of data transfers 3N+M according to the first invention.
However, according to the first invention, once the above-mentioned data has been transferred, all intermediaries involved in this communication have obtained the means to send it to the recipient. In contrast, with dereferencing, only the sender has the means to send the message to the recipient. In other words, in dereferencing, when sending data from any intermediary to the recipient,
While the above procedure is repeated again, according to the first invention, any intermediary can immediately transfer data directly to the recipient.

Further, the number of data transfers required for the above-mentioned dereference is the minimum, and normally more data transfers are required. On the other hand, in the first invention, communication can always be performed the above-mentioned number of times.

The second invention, the control method, allows the sender to release the data before the sender is notified of the recipient's location, for example to allow the sender to release the data even if the recipient is unknown. The processing time required for communication can be shortened when data needs to be transferred. When a caller's destination is in another Bromo server, conventional methods result in data transfers from the caller to the destination that are inter-processor transfers that require significant processing time.

On the other hand, according to the second invention, an intermediary is created in the same processor as the sender, and this intermediary is used as the sender's destination, so the transfer from the sender to the destination is performed as an intra-processor transfer. be able to.

Since intra-processor communication can be performed in a much shorter time than inter-processor transfer, the processing time required for communication can be reduced by the second invention.

Note that data is not transferred between the newly created intermediary and the sender's original destination unless the sender's original destination is the recipient, due to the effect of the first invention.

In the first invention, when the destination specified by the sender or the intermediary is the receiver, the number of data transfers increases compared to the conventional method, but according to the third invention, the conventional method also applies in this case. The number of data transfers required is the same. 1st
In the fourth invention, when the number of data is small, the number of data transfers is increased compared to the conventional method, but according to the fourth invention, even in this case, the number of data transfers can be the same as the conventional method.

(Example) Next, an example in a computer system including a plurality of processors will be described.

In this embodiment, the following items are assumed.

a The sender forwards the message he or she has generated to the destination before the recipient is notified.

b It is possible for multiple callers or intermediaries to forward to the same intermediary or recipient.

Under point a, the originator does not retain the message to be forwarded directly to the recipient. It is also possible that an intermediary retains the message. Also, according to item b, an intermediary or receiver may be sent messages from multiple senders or intermediaries.

Therefore, in this embodiment, the sender is not notified of the recipient's location. Also, the intermediary can hold any number of messages.

FIG. 10 shows an example of communication paths configured in the above system. 1, 2.3 are callers. 4 is the recipient. 5, 6, 7, 8.9 are intermediaries. 1st
The arrow in Figure 0 indicates that the sender or intermediary at the base of the arrow indicates that the intermediary or receiver pointed to by the arrow is designated as the transfer destination.

FIG. 1 shows the final transfer destination held by each sender and the intermediary when communication is carried out through the communication path shown in FIG.

FIG. 8 shows a data structure representing a message. 5
0 is an area that holds pointers to other messages. 51 is an area that holds the size of the message body; 52
is a variable length area that holds the message body.

FIG. 5 shows a data structure representing an intermediary.

The intermediary has an area 60 that holds the forwarding destination, and an area 61 that holds the pointer to the top of the list structure that holds the message.
and an area 62 that holds a pointer to the end.

FIG. 7 shows how a mediator holds multiple messages. In Figure 7, 70 is the intermediary, ? 1.72
．． 73 and 74 are messages, 50 is an area for holding a pointer to the next message, 61 is an area for holding a pointer to the beginning of the list structure, and 62 is an area for holding a pointer to the end of the list structure.

The intermediary 70 sends messages 71, 72 using the list structure.
Holds ゜73, 74.

FIG. 9 shows a data structure representing the location information of the transfer destination. This structure consists of an area 80 that holds a pointer to a transfer destination, and an area 81 that holds a value indicating whether the transfer destination is an intermediary or a recipient.

FIG. 2 is a flowchart showing the procedure of message transmission processing by the sender. In FIG. 2, when the caller is given the message to be sent and the location information representing the forwarding destination, in step 20, the caller determines whether the forwarding destination is in the same processor as the caller by looking at the forwarding destination's location information. do. If the determination result in step 20 is "Yes", the message is forwarded to the destination in step 24.If the determination result in step 20 is "no", an intermediary is created in step 21, and the At step 22, the message is forwarded, and at step 23, the forwarding destination is designated as the intermediary's forwarding destination by a procedure described later.

FIG. 3 is a flowchart showing the procedure for specifying a transfer destination for an intermediary. In FIG. 3, when the intermediary is given location information representing the forwarding destination, it determines in step 30 whether the forwarding destination is the recipient. Step 3
If the determination result in step 0 is "yes", the message is forwarded to the forwarding destination in step 35, and the forwarding destination is held in step 36. When the determination result in step 30 is "no", it is determined in step 31 whether or not the message is the last message to be sent by the S-based intermediary. When the determination result in step 31 is "yes", the message is transferred to the forwarding destination in step 35, and the forwarding destination is held in step 36. The determination result in step 31 is “No”
In this case, in step 32, a location confirmation message containing the location information of the intermediary is sent to the forwarding destination, and in step 3
3, wait for the arrival of the location notification message. When the location notification message arrives, in step 34 the intermediary or recipient indicated by the location information included in this message is the forwarding destination of the intermediary, in step 35 the message is forwarded to the forwarding destination, and in step 36 the forwarding destination is hold.

FIG. 4 is a flowchart showing the procedure of the recipient's receiving location notification process. In FIG. 4, the recipient receives step 4.
When the location confirmation message is received in step 41, a location notification message containing the location information of the recipient is sent to the sender or intermediary indicated by the location information included in this message.

FIG. 1 shows the process when a destination is actually designated as shown in FIG. 10 according to the procedure described above.

First, when the mediator 8 specifies a mediator 9 located in another processor as a transfer destination, a location confirmation message 101 containing the location information of the mediator 8 is sent to the mediator 9. 1st
Figure (a) shows the state in which the processing up to this point has been performed.

Next, when the sender 3 sends three messages 110 to the intermediary 8 as a transfer destination, an intermediary 7 is created in the same processor as the sender 3, and all messages are sent to the intermediary 7 as is. Furthermore, since the intermediary 8 in another processor is designated as the transfer destination for the intermediary 7, the intermediary 7
A location confirmation message 102 containing location information is sent to the intermediary 8. 1) shows the procedure for the processing up to this point.

Here, when the recipient is designated as the transfer destination by the intermediary 9, the intermediary 9 retains the recipient as the transfer destination and sends a location confirmation message containing the position information of the intermediary 8 held by the intermediary 9. 101 is sent to the recipient. FIG. 1(C) shows the state in which the processing up to this point has been performed.

Now, the receiver who has received the location confirmation message containing the location information of the intermediary 8 sends the location notification message 103 containing the receiver's location information number to the intermediary 8 .

FIG. 1(d) shows the state in which the processing up to this point has been performed.

The mediator 8 who received the location notification message sends a location confirmation message 102 containing the location information of the mediator 7 held by the mediator to the recipient, and holds the recipient as the transfer destination. FIG. 1(e) shows the state in which the processing up to this point has been performed.

The recipient who has received the location confirmation message containing the location information of the intermediary 7 sends the location notification message containing the receiver's location information to the intermediary 7. The intermediary 7 that received the location notification message sends the three messages 110 held by the intermediary to the recipient, and holds the recipient as a transfer destination. Figure 1) shows the state in which the processing up to this point has been performed.

Through the above processing, message 1 generated by sender 3
10 is sent directly to the recipient 4 through only one inter-processor communication without going through the intermediaries 8 and 9. Also, all intermediaries 7, 8, and 9 obtain the location information of the recipient 4.

Thereafter, in FIG. 10, when a mediator 8 in another processor is specified as a transfer destination of the mediator 6, a location notification message containing the location information of the mediator 6 is sent to the mediator 8. Since the intermediary 8 has the recipient as the forwarding destination, this message is immediately forwarded to the recipient, and in response, the recipient sends a location notification message to the intermediary 6, and as a result, the intermediary 6 transfers the recipient. hold as a destination.

Here, if caller 1 tries to send only one message to intermediary 6 located in another processor, intermediary 5 will be created in the same processor as sender 1, and the only message will be sent to intermediary 5. . Then, the intermediary 6 is specified as the forwarding destination of the intermediary 5, but since the message held by the intermediary 5 is the last message sent by the intermediary 5, the intermediary 5 directly transfers the message to the intermediary 6. Transfer to.

The intermediary 6 that has received this message directly forwards the message to the recipient since it already has the recipient as the forwarding destination.

FIG. 11 shows the state of the communication path formed by the above processing. In addition, in FIG. 11, 1,
2.3 is the sender, 4 is the receiver, 5,6°7.8.9 is the relay, and 90.91.92.93.94.95 is the processor.

Although the embodiments of the present invention have been described above, the data structures used in the above embodiments are not essential to the embodiments of the present invention. For example, in the present invention, the intermediary does not necessarily need to hold the transfer destination and the list structure at the same time, so the data structure representing the intermediary includes an area 60 holding position information representing the transfer destination as shown in FIG. This can be the same area that holds the pointer 6e pointing to the beginning of the list structure. This reduces the memory space required for data structures representing intermediaries. Also, messages do not need to be stored in a list structure, but may be stored in an array.

〔Effect of the invention〕

As explained above, according to the first invention, no matter how many processors the communication path formed by the intermediary is spread over, the message sent by the sender is transferred directly from the sender to the receiver, so that each The number of times the message is transferred is only one time, and the number of times the message is transferred can be reduced overall.

Further, according to the second invention, even if the sender sends a message before the recipient's location is notified in the first invention, the message sent by the sender is processed by the same processor as the sender ↓ Since the message is transferred directly from an intermediary to the recipient, the inter-processor transfer, which requires a large amount of processing time, only needs to be carried out once for each message, thereby reducing the processing time required for communication.

Further, according to the third invention, when the transfer destination specified by the sender or the intermediary in the first invention is the recipient,
Communication can be performed with an even smaller number of message transfers than in the first invention.

Similarly, according to the fourth invention, when only a small number of messages are transferred in the first invention, communication can be performed with an even smaller number of message transfers than in the first invention.

[Brief explanation of drawings]

Fig. 1 is a diagram showing the process of communicating via a communication channel according to the procedure of the present invention, Fig. 2 is a flowchart showing the procedure of message sending processing by the sender, and Fig. 3 is the procedure of processing when a transfer destination is specified by an intermediary. 4 is a flowchart illustrating the procedure of location notification processing by a recipient, 5 is a diagram illustrating an example of a data structure representing an intermediary, and 6 is another example of a data structure representing an intermediary. Figure 7 is a diagram showing an example of an intermediary that holds multiple messages in a list structure, Figure 8 is a diagram showing an example of a data structure representing messages, and Figure 9 is a data structure representing location information. FIG. 10 is a diagram showing an example of a communication path consisting of a sender, an intermediary, and a receiver, and FIG. FIG. 3 is a diagram illustrating an example of transfer destinations held by a person and a relay person. 3...Sender 4...Receiver 7.8.9...Relayer

Claims (4)

[Claims] (1) A sender generates and forwards a message, an intermediary receives and retransmits a message sent by the sender or a message retransmitted by another intermediary, and a receiver receives the message. In addition, in an interprocess communication control method that performs processing specified in a message, when the location of the receiver is unknown, the sender determines the first location to confirm the location of the receiver before forwarding the generated message. forwarding the confirmation message to a specified forwarding destination, and upon receiving the first location confirmation message, the receiver forwards a location notification message informing the location of the receiver to the generator of the location confirmation message. When the sender receives the location notification message, the sender retransmits the message it holds to the recipient who generated the location notification message, and the intermediary, upon receiving the designation of the retransfer destination, forwarding a second location confirmation message for confirming the location of the recipient to the re-transfer destination; continues to hold the location confirmation message, and the intermediary, upon receiving the location notification message, forwards the held message to the recipient who generated the location notification message. Communication control method. (2) When the transfer destination of the message generated by the sender is in a processor different from the processor where the sender is located, the sender creates a new intermediary in the processor where the sender is located, and this intermediary 2. The inter-process communication control method according to claim 1, wherein the transfer destination is specified as a re-transfer destination of the sender, and the message generated by the sender is further transferred to the intermediary. (3) If the sender can determine that the forwarding destination of the message generated by the sender is the recipient, the sender immediately transfers the message without forwarding the first location confirmation message and receiving the location notification message. The intermediary forwards the message generated by the sender first, and if the specified retransfer destination can be determined to be the recipient, the intermediary forwards the second location confirmation message and receives the location notification message. 2. The inter-process communication control method according to claim 1, wherein the held message is immediately transferred to the retransfer destination without retransfer. (4) If the number of messages to be forwarded is less than a certain number, the sender shall immediately forward the messages to the designated forwarding destination without forwarding the first location confirmation message and receiving the location notification message. If the intermediary can determine that the number of messages to be forwarded by the intermediary is less than or equal to a certain number, the intermediary does not forward the second location confirmation message and does not forward the second location confirmation message, and does not forward the location notification message. 2. The inter-process communication control method according to claim 1, wherein the held message is immediately transferred to a designated retransfer destination without waiting for the retransfer destination.