JP3224876B2 - Multiplexed communication distributed processing system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiplex communication path control apparatus which realizes a scalable broadcast communication mechanism by reducing an increase in the load on a communication path, which is a problem when applying broadcast communication to a large-scale distributed system. About.

[0002]

2. Description of the Related Art In recent years, with the diversification of requirements and the advancement of technology in various fields of computer systems, systems tend to be large-scale and complicated. For this reason, in configuring a computer system, there is an increasing demand for a distributed processing system that processes jobs using a plurality of computers. In this case, the distributed processing system is intended for a system element that is distributed and registered on a plurality of computers, for example, a system that cooperates and cooperates with each other while exchanging messages between processes.

In such a distributed processing system,
In order to improve the reliability of the system, a method is adopted in which the same processing is executed in parallel by a plurality of multiplexed system elements. In this case, if the processing cannot be executed unless each element is aware of the existence, position, and multiplicity of other related elements, it is impossible to construct a system that is excellent in scalability, reliability, maintainability, and processing. Can not.

In order to make each element independent,
This can be easily realized by using broadcast communication. However, when the number of computers connected to a single communication path becomes about 10 computers, the load on the communication path increases, and the performance of the entire system depends on the performance of the communication path. It is said that it is generally not suitable for constructing a large-scale system because of its limitations and difficulty in system expandability.

Further, in order for the multiplexing elements to make the same decision, it is required that the multiplexing elements receive the messages in the same order. Otherwise, they cannot make the same decision and may do different things.

[0006]

In order to solve such a problem, in a conventional multiplex communication system, a method is adopted in which each communication entity sequentially selects a communication path with a small load at the time of transmitting a message and sends a message to the communication path. I have. However, such a method cannot guarantee that multiplexed system elements will receive messages in the same order.

There are also systems using a crossbar switch system or an N-cube system as a communication channel for reducing the load on the communication channel. However, broadcast communication cannot be realized by the crossbar switch system. Although it can be realized, it is difficult to make the order of receiving messages the same because the message transmission path differs for each transmission source and each communication subject.

Further, in a system having a communication mechanism that guarantees that all computers connected to a single communication path receive a message in the same order, a communication path to be used is determined according to the destination of the message, and the message is transmitted. For example, the multiplexing elements can receive messages in the same order, and it is expected that the load on the communication path will be distributed. However, in an algorithm for determining a communication path to be used from a destination name, an element name having a high communication frequency is intensively allocated to a specific communication path by an application, and there is a possibility that the effect of multiplexing may not be obtained. Furthermore, there is a case where the frequency of use of each communication path changes during execution, and the load concentrates on a specific communication path.

The present invention has been made in view of the above circumstances, and can be applied to a large-scale system for broadcast communication, and multiplexed system elements are sent in the same order for the high reliability of the system. It is an object of the present invention to provide a multiplex communication distributed processing system which is excellent in system expandability and can guarantee reception of a multiplexed communication.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a multiplex communication distributed processing system using the following means.

[0011] The invention corresponding to claim 1 is characterized in that when a plurality of computers are connected to a multiplexed communication path and messages are exchanged via the communication path between system elements registered in the computers, In a multiplex communication distributed processing system in which a communication path to be used is determined according to a destination of a message, and the message is exchanged by broadcast communication via the determined communication path, a communication path limit is set for each communication path. Communication path limit load value storage means in which a load value is set;
Communication path load detecting means for obtaining a load per specified time of a designated communication path of a received message and registering the same as a current load value; and an assigned communication path management table for registering a destination name and an assigned communication path. An assigned communication channel management means for searching for a communication channel of a transmission destination and determining which destination is registered for each communication channel; and When there is no corresponding channel to be determined, a channel with a smaller load than the channel load detecting means is allocated as a transmission channel, and the destination name and the allocated channel are stored in the allocated channel management table of the allocated channel manager. Transmission channel allocation processing means for registering the communication channel limit load value storage means and the communication channel load when the transmission communication channel is allocated by the transmission communication channel allocation processing means. A communication channel load check processing means determines whether the current load value exceeds the limit load value by captures and limit load value and the current load value of the channel from the device out,
If the communication path load confirmation processing means determines that the current load value of the communication path allocated by the communication path load detection means exceeds the limit load value, the communication path allocation status management means recognizes the communication. Communication path assignment changing means for reassigning a part of the destination name group assigned to the path to a different communication path, wherein the communication path load confirmation processing means allocates the transmission path in the transmission communication path allocation processing means or the communication path When it is determined that the current load value of the transmission channel reallocated by the allocation changing means does not exceed the limit load value, a transmission request message is transmitted to the allocated communication channel.

According to a second aspect of the present invention, each computer is provided with a communication number management means for counting the number of communication times of the communication path, and the communication path load confirmation processing means detects a certain communication path detected by the communication path load detection means. When it is determined that the current load value exceeds the limit load value of the communication path set in the limit load value storage means, a number obtained by adding a predetermined number to the current number of communication times counted by the communication number management means. Is broadcast to all the computers connected to the communication path, and when the communication count management means of all the computers detects that the notified communication count has been reached, the specified allocation change name group is simultaneously changed. It is something to do.

[0013] In the invention according to claim 1, the current load value of a certain communication path detected by the communication path load detecting means is limited by causing the assigned communication path managing means to manage the use frequency for each message destination name. When the load exceeds the limit load value of the communication path set by the load value storage means, the communication path assignment changing means deletes a part of the destination name group assigned to the communication path grasped by the assigned communication path management means. In accordance with the frequency of use for each destination name and the load on the communication path detected by the communication path load detecting means, the communication path is allocated to the corresponding communication path.

Further, in the invention according to claim 1, when the current load value detected by the communication path load detection means of all communication paths exceeds the limit load value set in the limit load value storage means, The assignment changing means does not change the assignment of the message destination name.

[0015]

In the multiplex communication distributed processing system according to the first aspect, the present load value of a certain communication path detected by the communication path load detecting means is stored in the corresponding communication path stored in the limit load value storing means. When the limit load value is exceeded, a part of the destination name group assigned to the communication path grasped by the assigned communication path managing means by the assignment changing means can be reassigned to a different communication path. Assignment can be dynamically changed according to the frequency of use of each multiplexed communication path, and multiplexed system elements can receive messages in the same order.

In the multiplex communication distributed processing system according to the present invention, when the current load value of a certain communication path exceeds the limit load value of the communication path, the current number of communication times counted by the communication number management means. By instructing all computers to broadcast a message consisting of a number obtained by adding a predetermined number to all computers and changing the allocation at the same time by all computers, the communication frequency management means of all computers has reached the notified communication frequency. The assignment change name group designated upon detection can be changed at the same time in a distributed manner without having a centralized management mechanism.

In the multiplex communication distributed processing system according to the present invention, when a current load value of a certain communication path exceeds a limit load value of the communication path, a destination name is changed to another communication path. In order to determine whether to use the message, the assigned communication path management means manages the frequency of use for each message destination name, and a part of the destination name group assigned to the overloaded communication path is used for each destination name. By distributing the load of the communication path to the corresponding communication paths according to the load of the communication path detected by the communication path load detection means, it is possible to distribute the load of the communication path to a plurality of communication paths, thereby increasing the scale of the system. Can be realized.

Further, in the multiplex communication distributed processing system according to the first aspect, when the current load value of all communication paths exceeds the limit load value of the communication paths, the assignment of the message destination name is not changed. It is possible to prevent the assignment changing operation from being repeated.

[0019]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of the configuration of the entire multiplex communication distributed processing system according to the present invention. This system comprises a plurality of computers 2a, 2b, 2c,... Connected to three communication paths 1, 2, 3, as shown in FIG. These computers 2a, 2b, 2c,... Are connected to processing units 3a, 3b, 3c,... Which execute processing unique to each computer, and three communication paths 1, 2, 3, and exchange information between the computers. , Which perform the following processing. That is, the processing units 3a, 3b, 3c,.
Sends messages to the communication paths 1, 2, 3 via the communication processing sections 4a, 4b, 4c,... Or exchanges information with other computers by receiving messages on the communication paths.

Next, an example of the internal configuration of each of the computers 2a, 2b, 2c,... Will be described with reference to FIG. 2. Here, since each computer has the same configuration, the computer 2a will be described as a representative. In FIG. 2, a processing unit 3a is connected to a ROM 6 and a RAM 7 via a system bus 21, and is in charge of processing.
The communication processing unit 4a includes a PU (Dynamic Memo)
ry Access) controller 8, ROM10 and RAM1
1 is connected via a local bus 22 and has a CPU 9 in charge of communication processing.
A message is transmitted to the corresponding communication paths 1, 2, and 3 via communication units (SCU) 12 to 14, and the communication paths 1, 2, and 3 are transmitted.
3 is received via the corresponding SCUs 12, 13, and 14. Message exchange between the communication processing unit 4a and the processing unit 3a is performed via the DMA controller 8 connected to the system bus 21. The communication processing unit 4a
From the line receiver 15 and the line driver 1 provided between the SUC 12 and the communication path 3.
6. The transmission / reception is performed through a line receiver 17 and a line driver 18 provided between the SCU 13 and the communication path 2, and a line receiver 19 and a line driver 20 provided between the SCU 14 and the communication path 1, respectively.

Here, the SCUs 12 to 14 correspond to the communication channels 1 to 3.
Has a mechanism to automatically resend messages when a message collision is detected. The message transmission in the present embodiment means that the CPU 9 in the communication processing unit generates a transmission message and sends a transmission request to any of the selected SCUs 12 to 14, and the message is actually transmitted to the communication path. The timing of the request depends on the SCU, and the message is not always sent to the communication path at the same time as the transmission request.

As shown in FIG. 3, the communication processing section 4a includes a transmission communication path allocating processing section 23 for determining a communication path through which a message requested to be transmitted is transmitted. A channel load confirmation processing unit 24 for checking whether the value is not exceeded, a message transmitting unit 25 for transmitting a message to a designated communication channel, and an assigned channel management unit 26 for managing a used communication channel according to the destination of the message. A communication path allocation status management unit 27 that manages destination names assigned to each communication path, a communication path limit load value storage unit 28 that sets a limit load value for each communication path, and changes a destination path allocation communication path. A communication channel allocation change unit 29; a communication channel load value detection unit 30 for detecting a current load value for each communication channel; a communication frequency management unit 31 for counting the number of times of communication on the communication channel; Received message determination processing unit 32 to check whether the received in, and a message receiving unit 33 for receiving a message from the channel.

As shown in FIG. 4, the assigned communication path management section 26 holds an assigned communication path management table indicating which communication path is assigned to each destination name. For this assigned communication path management table, the destination process name in the destination name field and the number of the communication path used for transmission to the destination process name in the destination name field in the assigned communication path field are entered in the destination communication path field. Indicates the number of the destination communication path when changing the assignment of the destination process name to another communication path (initial value is 0), and the load column indicates the number of times of communication within a predetermined time to the destination process name. Register, and the Next-ptr field contains an address for tracing the destination process name assigned to the same communication path (the initial value is
NIL (-1)) is set.

As shown in FIG. 5, the communication channel assignment status management unit 27 holds a communication channel assignment status management table indicating which destination is registered for each communication channel. In this channel assignment status management table, the channel numbers are set in the channel number column by the number of the connected channels from 1;
The reassignment flag field indicates whether or not the load on the communication path exceeds the limit load value and a reassignment request has been issued. When the initial value is OFF and the reassignment request has been issued, the communication path is switched. The number of times of communication indicating the timing is set. Further, an address (initial value is NIL (-1)) indicating a destination name assigned to the communication channel in the assignment communication channel management table is set in the pointer to the assignment destination column. The communication path limit load value storage unit 28 and the communication path load detection unit 30 hold the limit load value and the current load value for each communication path shown in FIGS. 6 and 7, respectively.

Next, the operation of the multiplex communication distributed processing system configured as described above will be described. Here, as shown in FIG. 8, a plurality of processes are registered on each of the computers 2a, 2b, 2c,. A case where a given task is performed while exchanging messages will be described. In other words, the computer 2a process A ₁ is registered in the process A ₂ and C the computer 2b is, computer process to 2c B ₁ and D
_1, the process B ₂ and D ₂ are respectively registered in the computer 2d. It is also assumed that the communication path is tripled.

First, referring to FIG. 8, a process A in the computer 2a
_The case where 1 sends a message to the process C in the computer 2b will be described with reference to FIG. 1, FIG. 3, FIG. 8, FIG. 9, FIG. In this case also intended to not transmitted previously to the process A ₁ addressed message which computer.
That is, a process when a message is sent to a new destination (a destination not registered in the assigned communication management table) and a message of the new destination is received will be described. Further, for the sake of simplicity, it is assumed that the system has just been started and has not been communicated once.

[0028] When the message transmission request addressed to the process C is Dasa to the transmission processing section 4a from the computer processes A ₁ that is registered in the processing unit 3a in 2a, the transmission of the transmission processing unit 4a communication channel allocation processing section 23 Makes an inquiry to the assigned communication path management unit 26 as to whether a communication path to which a message addressed to the process C is to be sent is assigned. Then, the flowchart shown in FIG. 15 is started. First, the assigned communication path management unit 2
In step 6, the communication path addressed to the process C is obtained by searching the assigned communication path management table. In this case, since the communication path has not been registered, the fact is returned to the transmission communication path allocation processing unit 23 (step S1).

When the transmission channel allocation processing unit 23 determines that the destination has not been registered (step S2), the transmission channel load detection unit 30
Then, the corresponding communication path is obtained by inquiring about the communication path with the smallest load (step S3), and the process C of the transmission destination and the obtained communication path are notified to the assigned communication path management unit 26 and the communication path allocation status management unit 27. In this example, in the first communication after system startup, the loads on all communication paths are zero and equal, so that the communication path 1 having the smallest communication path number is set as the allocation communication path, and the allocation communication path management table shown in FIG. Is registered in the communication path assignment status management table (step S4). That is, the assigned communication path management unit 2
In 6, the destination process name C in the destination name column of the allocated communication path management table, the communication path 1 allocated in the allocated communication path field,
In the destination communication path column, 0 is registered because the destination is undecided, and in the load column, 1 is registered because it is the first communication to the process C. In the communication channel assignment status management unit 27, in the destination pointer column of the row corresponding to the assigned communication channel 1 in the assignment channel management table,
The address indicating the row corresponding to the destination name in the assigned communication path management table is registered, and the value (OFF) of the reallocation flag is returned to the transmission communication path allocation processing unit 23. The transmission channel allocation processing unit 23 takes as arguments the OFF value of the re-allocation flag passed from the channel allocation status management unit 27, the transmission request message passed from the processing unit 3a, and the obtained assigned channel number 1. Then, the communication path load confirmation processing unit 24 is started.

The communication path load confirmation processing unit 24 determines whether or not the passed reassignment flag is OFF (step S).
5). In this case, since it is determined to be OFF, the limit load value and the current load value of the communication path 1 are obtained by querying the communication path limit load value storage unit 28 and the communication path load detection unit 30, and the current load value It is determined whether or not the load value has been exceeded (step S10). Since the communication channel 1 has not exceeded the limit load value immediately after system startup, the transmission request message is passed to the message transmission unit 25 so as to be transmitted to the assigned communication channel 1.

The message transmitting unit 25 transmits the transmission request message to the specified assigned communication channel 1 (step S1).
8) Notify the communication count management unit 31 that communication has been performed. The communication count management unit 31 sets the communication count to +1 (step S19).

When the computer 2b, 2c,... Receives the message addressed to the process C, the flowchart shown in FIG. 16 is started, and the message receiving unit 33 in the communication processing units 4b, 4c,. It is determined whether the received message is a request message (step S21). In this case, since the message is addressed to the process C, the communication path load detection unit 30 is notified of the number 1 of the communication path that has received the message, and the communication number management unit 31 is also notified that the message has been received.
The communication path load detection unit 30 obtains the load of the specified communication path 1 per fixed time and registers the load in the current load value table (step 22). Further, the number-of-communications management unit 31 sets the number of communication times to +1 (step S23).

When the message receiving unit 33 confirms that the updating has been completed, the message receiving unit 33 sends the received message including the destination name process C and the communication channel number 1 that has received it to the received message determination processing unit 32. The received message determination processing unit 32 determines whether the destination name process C is registered in the assigned communication path management table (step S24). In this case, since no destination name is registered in the first communication after the system is started, the message receiving channel number 1 is used as the allocated channel as shown in FIG. Register it in the management table (step S26). In other words, the assigned channel management unit 26 assigns the channel number 1 of the received message to the destination name column of the assigned channel management table, assigns 0 to the destination channel column because the destination is undetermined, and assigns the destination to the process C in the load column. Since it is the first communication, 1 is registered.

The communication path assignment status management unit 27 stores the row corresponding to the destination name C in the assigned communication path management table in the destination pointer column of the row corresponding to the assigned communication path 1 in the communication path assignment status management table. The address pointed to is registered, and the value (OFF) of the reallocation flag is returned to the received message determination processing unit 32. The received message determination processing unit 32 compares the OFF value of the re-allocation flag obtained from the communication channel assignment status management unit 27 with the number of communications held by the communication count management unit 31 to determine whether or not it is the communication channel switching timing. Is determined (step S27). In this case, the reallocation flag is OFF
Therefore, the received message is passed to the processing unit as it is, not at the switching timing (step S31).

Next, a message transmission procedure and a reception procedure when a communication path is determined for each destination name as shown in FIG. 10 will be described. That is, when the process C is registered in the communication channel 1, the process A is registered in the communication channel 2, and the process B is registered in the communication channel 3, the process C registered in the computer 2b is registered in the computers 2c and 2d. A case where a message is sent to the processed process B (B ₁ , B ₂ ) will be described. However, for the sake of simplicity, it is assumed that the load on each communication path is sufficiently small and that it is not necessary to switch the communication paths.

Upon receiving a message transmission request addressed to process B from process C registered in processing unit 3b in computer 2b, transmission communication channel allocation processing unit 23 in transmission processing unit 4b sends a process Inquires whether a channel to send a message addressed to B has been assigned,
The assigned communication path management unit 26 obtains a communication path addressed to the process B by searching the assigned communication path management table.
In this case, since the process B has been assigned to the communication path 3, the fact is returned to the transmission communication path allocation processing unit 23 (step S1). The transmission channel allocation processing unit 23 determines that the communication channel to be used is already registered and is the communication channel 3 (step S
2). At this time, the communication path load confirmation processing unit receives the OFF value of the reassignment flag of the communication path 3, the transmission request message passed from the processing unit 3b, and the obtained number 3 of the allocated communication path as arguments to the communication path allocation status management unit 27. Start 24.

The communication path load confirmation processing section 24 determines whether or not the passed reassignment flag is OFF (step S).
5). In this case, since it is OFF, the limit load value and the current load value of the communication path 3 are obtained by querying the communication path limit load value storage unit 28 and the communication path load detection unit 30, and the current load value exceeds the limit load value. Since the transmission request message has not been transmitted, the message is transmitted to the message transmission unit 25 so as to transmit the transmission request message to the assigned communication path 3.

The message transmitting unit 25 transmits the transmission request message to the specified assigned communication channel 3 (step S1).
8) Notify the communication number management unit 31 of the transmission. The communication count management unit 31 sets the communication count to +1 (step S19).

The communication processing units 4a, 4c, 4 of the computers 2a, 2c, 2d,.
The message receiving unit 33 in d,... determines whether the received message is a communication switching request message (step S21). In this case, since the message is addressed to the process B, the communication load detecting unit 30 is notified of the number 3 of the communication path that has received the message, and the communication count management unit 31 is also notified that the message has been received. The communication load detection unit 30 obtains a load of the designated communication path 3 per fixed time, and registers the load in the current load value table (step S22). Communication count management unit 3
At 1, the number of times of communication is set to +1 (step S23). When the message receiving unit 33 confirms that the updating has been completed, the message receiving unit 33 sends the received message including the destination name process B and the communication path number 3 that has received the received message to the received message determination processing unit 32. This received message determination processing unit 32
Then, it is determined whether or not the destination name process B is registered in the assigned communication path management table (step S24). In this case, since it is already registered as shown in FIG.
The assigned communication path management unit 26 recalculates the load column corresponding to the process B to obtain the load for a certain period, registers the result 9 (step S25), and the communication path allocation state management unit 27 Channel 3 used in the management table
Is returned to the received message determination processing unit 32. In the received message determination processing unit 32, the O of the reallocation flag obtained from the communication channel allocation status management unit 27 is
By comparing the FF value with the number of times of communication held by the number-of-times-of-communications management unit 31, it is determined whether or not it is the timing of switching the communication path (step S27). Instead, the received message is passed to the processing unit as it is (step S3
1).

Next, when a communication path is determined for each destination name as shown in FIG. 10, a procedure for transmitting and receiving a message addressed to the process D which has not been registered at that time will be described. That is, the process C is in the communication path 1 and the communication path 2 is in the communication path 2.
In the case where the process A is registered in the communication path 3 and the process B is registered in the communication path 3, the process D registered in the computers 2c and 2d from the process C registered in the computer 2b (D
₁ , D ₂ ) will be described. However, for the sake of simplicity, it is assumed that the load on each communication path is sufficiently small and communication path switching is not necessary.

Upon receiving a message transmission request addressed to process D from process C registered in processing unit 3b of computer 2b, transmission communication channel allocation processing unit 23 in transmission processing unit 4b sends a process Inquires whether a channel to send a message addressed to D is assigned,
The assigned communication path management unit 26 obtains the communication path addressed to the process D by searching the assigned communication path management table. In this case, since the communication path has not been registered, the fact is returned to the transmission communication path assignment processing unit 23 (step S1). .

When the transmission channel allocation processing unit 23 determines that the destination is not registered (step S2), the communication channel load detection unit 30
Then, the corresponding communication path is obtained by inquiring about the communication path with the smallest load (step S3), and the process D of the transmission destination and the obtained communication path are notified to the assigned communication path management unit 26 and the communication path allocation status management unit 27. In this case, assuming that the communication channel 1 has the smallest load, the communication channel 1 is set as the assigned communication channel, and registered in the assigned communication channel management table and the communication channel assignment status management table as shown in FIG. 11 (step S4). . In other words, the assigned communication path management unit 26 sets the destination process name D in the destination name section of the assigned communication path management table, the communication path 1 assigned to the assigned communication path section, and the destination undetermined destination in the destination communication path section. Therefore, 0 is registered in the load column because it is the first communication addressed to the process D. Further, a pointer is set to Next-Ptr of the destination C assigned to the same communication path 1 as the destination D so as to point to the row of the destination D. In the communication channel allocation status management unit 27, since the assigned communication channel 1 has already been registered, the value (OFF) of the re-allocation flag of the communication channel 1 is transmitted to the transmission channel allocation processing unit 23.
To return. The transmission channel allocation processing unit 23 uses the OFF value of the re-allocation flag passed from the channel allocation status management unit 27, the transmission request message passed from the processing unit 3b, and the obtained assigned channel number 1 as arguments. Communication path load confirmation processing unit 24
Start

The communication path load confirmation processing section 24 determines whether or not the passed reassignment flag is OFF (step S5). In this case, since it is OFF, the limit load value and the current load value of the communication path 1 are obtained by querying the communication path limit load value storage unit 28 and the communication path load detection unit 30.
It is determined whether or not the current load value exceeds the limit load value (Step S10). Since the current load value of the communication channel 1 does not exceed the limit load value, the transmission request message is passed to the message transmission unit 25 so as to be transmitted to the assigned communication channel 1.

The message transmitting unit 25 transmits the transmission request message to the specified assigned communication channel 1 (step S1).
8) Notify the communication number management unit 31 of the transmission. The communication count management unit 31 sets the communication count to +1 (step S
19).

The communication processors 4a, 4c, 4 of the computers 2a, 2c, 2d,.
The message receiving unit 33 in d,... determines whether the received message is a communication channel switching request message (step S21). In this case, since the message is addressed to the process D, the communication path load detection unit 30 is notified of the number 1 of the communication path that has received the message, and the communication count management unit 31 is also notified that the message has been received. The communication path load detection unit 30 obtains a load per specified time of the specified communication path 1 and registers it in the current load value table (step S22). The communication count management unit 31 sets the communication count to +1 (step S2).
3). When the message receiving unit 33 confirms that the updating has been completed, the message receiving unit 33 passes the received message including the destination name process D and the communication channel number 1 that has received it to the received message determination processing unit 32. The received message determination processing unit 32 determines whether the destination name process D is registered in the assigned communication path management table (step S2).
4). In this case, since the message has not been registered yet, the message receiving channel number 1 is set as the allocated channel and registered in the allocated channel management table and the channel allocation status management table as shown in FIG. 11 (step S26). The communication path management unit 26 stores the destination process name D in the destination name field of the assigned communication path management table, the number 1 of the channel receiving the message in the assigned communication path field, and the destination undetermined in the destination communication path field. Therefore, 0 is registered in the load column because it is the first communication addressed to the process D. Further, in the Next-Ptr column, there is a destination C already assigned to the same communication path 1 as the destination D. Therefore, to chain the destinations assigned to the same communication path, the Next-Ptr in the row of the destination C is chained. Is set to point to the row of the destination D. Communication path assignment status management unit 2
In step 7, since the assigned communication channel 1 has already been registered, the value (OFF) of the reallocation flag of the communication channel 1 is returned to the received message determination processing unit 32. The received message determination processing unit 32 compares the OFF value of the re-allocation flag obtained from the communication channel allocation status management unit 27 with the number of communication times held by the communication frequency management unit 31 to determine whether or not it is the communication channel switching timing. (Step S27) In this case, the reassignment flag is OFF, so that the received message is passed to the processing unit as it is, not at the switching timing (Step S31).

Next, when the communication path is determined for each destination name as shown in FIG. 11, the load of the communication path 1 exceeds the limit load value, and the destination name assigned to the communication path 1 is changed to another load. The procedure for changing the assignment to a communication path with a small communication path will be described. That is, the processes C and D are registered in the communication channel 1, the process A is registered in the communication channel 2, and the process B is registered in the communication channel 3.
The current load value is 0.5 when the limit load value of communication channel 1 is 0.4
, The process C registered in the computer 2b to the process D registered in the computers 2c and 2d
A case where a message is sent to (D ₁ , D ₂ ) will be described.

When the transmission processing unit 4b receives a message transmission request addressed to the process D from the process C registered in the processing unit 3b of the computer 2b, the transmission channel allocation processing unit 23 in the transmission processing unit 4b An inquiry is made to the communication path management unit 26 as to whether a communication path to which a message addressed to the process D is to be transmitted is assigned.
A communication path to the destination is obtained. In this case, since the process D is assigned to the communication path 1, the fact is returned to the transmission communication path allocation processing unit 23 (step S1).

The transmission channel allocation processing section 23 determines that the communication channel to be used has already been registered and is the communication channel 1 (step S
2). At this time, the communication path allocation status management unit 27 is requested to determine the reallocation flag of the communication path 1, and the reallocation flag is turned off.
The communication path load confirmation processing section 24 is activated by using the value, the transmission request message passed from the processing section 3b and the obtained assigned communication path number 1 as arguments.

The communication path load confirmation processing section 24 determines whether or not the passed reassignment flag is OFF (step S5). In this case, since it is OFF, the limit load value and the current load value of the communication path 1 are obtained by querying the communication path limit load value storage unit 28 and the communication path load detection unit 30.
It is determined whether or not the current load value exceeds the limit load value (Step S10). In this case, since the current load value of the communication channel 1 is 0.5 and the limit load value is 0.4, it is determined that the limit is exceeded (step S10). However, other communication paths 2
Since the current load values of (3) and (3) do not exceed the respective limit load values, it is not determined that the current load value exceeds the limit value in all communication paths (step S11). Therefore, it is determined that it is necessary to change the destination assigned to the communication channel 1 to another communication channel with a smaller load, and the communication channel allocation change unit 29 is requested to use the number 1 of the allocation change target communication channel as an argument. I do.

The communication channel assignment changing unit 29 checks the use frequency (load) of each destination assigned to each communication channel, and determines the assigned communication channel management unit 26 and the communication channel assignment status management unit 27.
To know that the loads on the destinations A, B, C, and D are 3, 8, 7, and 9, respectively (step S12). Next, in order to determine the destination of the destination name, the current load value of each communication path is obtained from the communication path load detection unit 30, and the loads of the communication paths 1, 2, 3 are 0.5, 0.2, 0. 3 (step S13). Therefore, in order to make the load of all communication paths the most balanced state, among the destinations C and D assigned to the communication path 1 in which the communication path load value exceeds the limit load value, the destination C is loaded. (Step S1).
4).

Based on the result, the assigned communication management table and the communication assignment status management table are changed as shown in FIG. That is, it instructs the assigned communication path management unit 26 to set the destination communication path number 2 in the mobile communication column of the destination C to be moved in the assigned communication path management table (step S15). Further, the communication channel allocation status management unit 27 is changed in order to change the assigned communication channel when the value becomes a value obtained by adding a predetermined number to the current number of times of communication, for example, 100 when the number of times of current communication 90 is added to 100. It instructs to set 100 to the reassignment flag corresponding to the communication path 1 exceeding the limit load value in the path allocation status management table (step S16).
Then, in order to change the allocation at the same time, a format switching request message shown in FIG. 12 is broadcast (step S17). The destination address in FIG. 12 contains address information indicating a broadcast message, the source address contains the address information of the computer transmitting the switching request message, and the group of reassigned names contains the destination C to be reassigned. The destination channel number is set to 2, which is the destination channel of the destination C, and the number of switching communications is set to 100, which is the number of communications for switching. The communication path load confirmation processing unit 24, after confirming that the above series of processing has been completed,
In order to transmit the message requested to be transmitted by the processing unit, the message is transmitted to the message transmitting unit 25 so that the transmission request message is transmitted to the assigned communication path 1.

The message transmitting unit 25 transmits the transmission request message to the specified assigned communication channel 1 (step S1).
8) Notify the communication number management unit 31 of the transmission. The communication count management unit 31 sets the communication count to +1 (step S19).

Computer 2 that has received the switching request message
a, 2c, 2d,... communication processing units 4a, 4c, 4d,.
The message receiving unit 33 determines that the received message is a communication switching request message (step S2).
1) As shown in FIG. 13, the assigned communication path management table and the communication path assignment status management table are changed. That is, when the message receiving unit 33 determines that the message is a switching request message, the message receiving unit 33 switches the destination C, which is a group of reassigned names, the destination channel number 2, and the number 100 of switching communications, to the argument. Notify that this is a request.
The received message determination processing unit 32 instructs the assigned communication path management unit 26 to set the destination communication path number 2 in the mobile communication field of the destination C to be moved in the assigned communication path management table, and assigns the communication path. The status management unit 27 is instructed to set the reassignment flag corresponding to the registered communication channel 1 of the destination C in the communication channel assignment status management table to 100 (step S32).

The message transmitted / received before the switching timing, including the message addressed to the process D received following the switching message, is performed via the original allocated communication channel.

Next, transmission and reception processing after the switching request is broadcast and before the switching timing comes will be described.
Here, as shown in FIG. 13, a communication path is determined for each destination name, and when the current number of communications is 95, the process A ₂ registered in the computer 2a to the process D (registered in the computers 2c and 2d) D ₁ , D ₂ ) will be described when a message is transmitted via the communication path 1.

[0056] Computer 2a of the processing unit transmitting the communication processing unit 23 of the transmission processing unit 4a which has received the message transmission request addressed to the process D from the process A ₁ registered in 3a, the process D in the allocation channel management unit 26 It is inquired whether a communication path to which a message addressed to the destination is to be assigned, and the assigned communication path management unit 26 obtains a communication path addressed to the process D by searching the assigned communication path management table. Since the communication channel 1 is assigned to D, the fact is returned to the transmission channel allocation processing unit 23 (step S
1). The transmission channel allocation processing unit 23 determines that the communication channel to be used has already been registered and is the communication channel 1 (step S2).
At this time, the communication path allocation status management unit 27 is requested to determine the reassignment flag of the communication path 1, and the value of the allocation flag, ie, 10
The communication channel load confirmation processing unit 24 is activated by using 0 as an argument together with the transmission request message passed from the processing unit 3a and the obtained assigned communication channel number 1.

The communication path load confirmation processing unit 24 determines whether or not the passed reassignment flag is OFF (step S).
5). In this case, since the reassignment flag value is 100 and not OFF, an inquiry is made to the communication channel assignment changing unit 29 to check whether or not the communication channel is at the switching timing. When the current number of times of communication is obtained from the number-of-times-of-communications management unit 31 at 95, the communication-line-allocation changing unit 29 determines that it is not the switching timing (step SS6) because the reassignment flag value is not 100 or more at step 95 (step SS6). This is returned to the processing unit 24.

When notified that the timing is not the switching timing, the communication path load confirmation processing section 24 transmits a message so as to transmit the transmission request message to the assigned communication path 1 in order to transmit the message requested to be transmitted from the processing section 3a. Hand over to part 25.

The message transmitting unit 25 transmits the transmission request message to the specified assigned communication channel 1 (step S1).
8) Notify the communication number management unit 31 of the transmission. The number-of-communications management unit 31 increases the number of times of communication by +1 to 96 (step S19).

The communication processing units 4b, 4c, 4 of the computers 2b, 2c, 2d,.
The message receiving unit 33 in d,... determines whether the received message is a communication switching request message (step S21). In this case, since the message is addressed to the process A, the communication load detection unit 30 is notified of the number 1 of the communication path that has received the message, and the communication count management unit 31 is also notified that the message has been received. The communication load detection unit 30 obtains the load of the specified communication channel 1 per fixed time and registers the load in the current load value table (step S22). Communication count management unit 3
In step 1, the number of communications is incremented by 1 to 96 (step S2).
3). When the message receiving unit 33 confirms that the updating has been completed, the message receiving unit 33 passes the received message including the destination name process D and the communication channel number 1 that has received it to the received message determination processing unit 32. The received message determination processing unit 32 determines whether the destination name process D is registered in the assigned communication path management table (step S2).
4). In this case, since it is already registered as shown in FIG. 13, the allocated communication path management unit 26 recalculates the load column corresponding to the process D, obtains the load for a certain period, and registers the result value ( In step S25, the communication channel allocation status management unit 27 passes the value 100 of the reassignment flag of the used communication channel 1 in the communication channel allocation status management table to the received message determination processing unit 32. This received message determination processing unit 3
In 2, the value of the re-allocation flag 100 obtained from the communication path allocation status management section 27 is compared with the number of communication 96 held in the communication number management section 31 to determine whether or not it is the communication channel switching timing. (Step S27) In this case, since the number of times of communication (96) does not exceed the reallocation flag value (100), it is determined that it is not the switching timing, and
The received message is passed to the processing unit as it is (step S3
1).

Next, when the communication path is determined for each destination name as shown in FIG. 13, the number of times of communication reaches 100,
The processing at the time of changing the destination assigned to the communication path 1 will be described. That is, since the number of communication times is the sum of each of the three communication paths, the number of communication times is 1
If the communication using the communication channel 1 occurs when the communication channel number becomes 00 or more, the communication channel 1 is used as shown in the assigned communication management table.
Is changed to the communication path 2. When here a number of communications 100, will be described in which through a communication path 1 from the computer processes B ₁ registered in 2c addressed process C registered in the computer 2b transmits a message.

[0062] Computer transmission channel allocation processing section 23 of the transmission processing unit 4c for receiving the message transmission request from the process B _1, which is registered in the processing unit 3c of the addressed process C in 2c is
The assignment channel management unit 26 is queried as to whether a channel to which a message destined for the process C is to be sent is assigned, and the assignment channel management unit 26 searches the assignment channel management table to thereby determine the process C address. A communication path is obtained. In this case, since the process C is assigned to the communication path 1 and 2 is registered in the destination communication path, the fact is returned to the transmission communication path allocation processing unit 23 (step S1). . Since the communication channel to be used has already been registered, the transmission channel allocation processing unit 23 determines that the communication channel is the communication channel 1 (step S2). At this time, the communication path allocation status management unit 27 is requested to determine the reassignment flag of the communication path 1, and the value of the reassignment flag, ie, 100
Together with the transmission request message passed from the processing unit 3c and the determined assigned communication channel number 1 and destination communication channel number 2 as an argument to activate the communication channel load confirmation processing unit 24.

The channel load confirmation processing section 24 determines whether or not the passed reassignment flag is OFF (step S).
5). In this case, since the reallocation flag value is 100 and not OFF, the inquiry is made to the communication path assignment changing unit 29 to check whether the communication path is at the switching timing. When the current number of times of communication is obtained from the number-of-times-of-communications management unit 31, the communication-path-allocation changing unit 29 determines that it is a switching timing because the value of the number of times is equal to or more than 100 at step S <b> 100
6). At this time, the assigned communication path management table and the communication path assignment status management table are changed as shown in FIG. That is, the destination C in which the destination communication path is registered among the destinations assigned to the communication paths in the assigned communication path management table is rewritten to be moved to the specified communication path 2. That is, the assigned communication path of the destination C is rewritten to 2 which has been set as the movement destination communication path, the movement destination communication path is cleared to 0, and Next
The -Ptr column is changed to indicate that only the destination D is allocated to the communication path 1 and that the destinations A and C are allocated to the communication path 2 (step S7). Subsequently, the reallocation flag in the communication path assignment status management table is cleared to OFF (step S8), and the destination pointer connecting the allocated communication path management table is rewritten (step S9). When confirming that the above-described series of processing is completed, the communication path load confirmation processing unit 24 transmits the transmission request message to the original allocated communication path 1 so as to transmit the message requested to be transmitted from the processing unit 3c. To the message transmitting unit 25.

The message transmitting unit 25 transmits the transmission request message to the specified assigned communication channel 1 (step S1).
8) Notify the communication number management unit 31 of the transmission. The number-of-communications management unit 31 increases the number of times of communication by +1 to 101 (step S19).

The communication processors 4a, 4b, 4 of the computers 2a, 2b, 2d,.
The message receiving unit 33 in d,... determines whether the received message is a communication switching request message (step S21). In this case, since the message is addressed to the process C, the communication load detection unit 30 is notified of the number 1 of the communication path that has received the message, and the communication count management unit 31 is also notified that the message has been received. The communication load detection unit 30 obtains the load of the specified communication channel 1 per fixed time and registers the load in the current load value table (step S22). The communication number management unit 31 increments the number of communication times by one and sets 101 (step S23). When the message receiving unit 33 confirms that the updating has been completed, the message receiving unit 33 passes the received message including the destination name process C and the communication channel number 1 that has received the received message to the received message determination processing unit 32. The received message determination processing unit 32 determines whether the destination name process C is registered in the assigned communication path management table (step S24). In this case, since it is already registered as shown in FIG. 13, the assigned communication path management unit 26 recalculates the load column corresponding to the process C, obtains the load for a certain period, and registers the result value ( In step S25, the communication channel allocation status management unit 27 returns the value 100 of the reassignment flag of the used communication channel 1 in the communication channel allocation status management table to the received message determination processing unit 32. The received message determination processing unit 32 compares the value 100 of the re-allocation flag obtained from the communication channel assignment status management unit 27 with the number of communications 101 held in the communication count management unit 31 to determine whether the communication channel switching timing has been reached. (Step S27). In this case, the number of communications (101) is changed to the reallocation flag value (10).
0), the switching timing is determined.
At this time, the assigned communication path management table and the communication path assignment status table are changed as shown in FIG. That is, of the destinations assigned to the communication path 1 in the assigned communication path management table, the destination C in which the destination communication path is registered is rewritten to be moved to the specified communication path 2. That is, destination C
Is rewritten to the communication channel 2 set as the destination communication channel, the destination communication channel is cleared to 0, and the Next-Ptr
The column is changed to indicate that only the destination D is allocated to the communication path 1 and the destinations A and C are allocated to the communication path 2 (step S28). Subsequently, the reallocation flag in the communication path assignment status management table is cleared to OFF (step S29),
The destination pointer connecting the allocated communication path management table and the communication path allocation status management table is rewritten (step S30).
After these processes are completed, the received message determination processing unit 32 passes the received message to the processing unit 3c (Step S3).
1).

After the transmission / reception processing is completed, the next communication is performed using the newly determined communication path for each destination. For example, the message of the destination C is transmitted and received using the communication path 2.

As can be seen from the above example, the communication channel of the message destination can be changed simultaneously by a plurality of computers without having a centralized management unit and without synchronization between the plurality of computers.

In the above embodiment, the number of times of communication is managed by the number of times of communication of the three communication paths by the number of times of communication management unit 31.
This can also be performed by counting the number of times of communication for each communication path. In this case, the communication count management unit 31 holds the communication count for each communication path to determine whether or not it is the switching timing.

The above-described embodiment is a method for managing a plurality of communication paths in a single communication processing unit. Although the communication apparatus is compact and excellent in economy, the number of communication paths is reduced according to the load of the communication path. It cannot be easily increased or decreased. Therefore, a communication processing unit can be provided for each communication path. In this case, the processing unit selects a communication path to which a message is to be transmitted.However, it is possible to easily increase or decrease the number of communication processing units according to the system scale and the load of the communication path and change the communication path. It is possible to cope with system expansion and contraction.

Further, in the above embodiment, the limit load value for each communication path of a certain computer is changed, and the limit load value of each computer for the same communication path is made the same. That is, the computers 2a, 2
In each of b, 2c,..., the limit load value for the communication path 1 is 0.4. By changing this for each computer, a message transmission request is issued from a plurality of computers at the same time, and it is possible to avoid that a plurality of computers simultaneously determine that the communication path load limit value is exceeded and broadcast the switching request. For example, the limit load value for the communication path 1 of the computer 2a is 0.4
However, by changing the limit load value for the communication path 1 of the computer 2b to be 0.35,
Even if the computers 2a and 2b try to transmit a message at the same time, only the computer 2b broadcasts the switching request. Thus, the complexity of the switching operation can be reduced.

In this embodiment, even when the destination name does not exist in the own computer, the received message is passed to the processing unit. However, by managing the process names registered in the own computer, the received message is sent to the own computer. It is also possible to delete a message addressed to an unregistered process in the communication processing unit so as not to pass a useless message to the processing unit.

[0072]

As described above, according to the present invention, the load on the communication path can be distributed to a plurality of communication paths, and the system can be made large-scale. Since the same message reception order of the elements is also guaranteed, there is no need to allocate a communication path to be used for each system element in advance, and it is possible to respond to dynamic addition of system elements and fluctuations in communication path load. It is possible to provide a multiplex communication distributed processing system that is not affected by movement or copying of system elements.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a multiplex communication distributed processing system according to the present invention.

FIG. 2 is a configuration diagram in a computer in the embodiment.

FIG. 3 is a block diagram showing a configuration example of a communication processing unit in the computer.

FIG. 4 is a diagram showing a configuration example of an assigned communication path table held by an assigned communication path management unit in the communication processing unit of FIG. 4;

FIG. 5 is a diagram showing an example of the configuration of a communication channel assignment status table held by a communication channel assignment status management unit.

FIG. 6 is a diagram showing a configuration example of a limit load value setting table held in a communication channel limit load value storage unit.

FIG. 7 is a diagram showing a configuration example of a communication path load table held by the communication path load detection unit.

FIG. 8 is a view showing an example in which system elements are registered in the embodiment.

FIG. 9 is a diagram showing a situation in which a single destination is registered in an assigned communication path table and a communication path assignment status table.

FIG. 10 is a diagram showing a situation where three destinations are registered in an assigned communication path table and a communication path assignment status table.

FIG. 11 is a diagram showing a situation where four destinations are registered in an assigned communication path table and a communication path assignment status table.

FIG. 12 is a diagram showing a message format which is a configuration example of a communication path switching request message.

FIG. 13 is a diagram showing a state of a limit load setting table, a communication path load table, an assigned communication path table, and a communication path assignment status table when the current load value of the communication path exceeds the limit load value.

FIG. 14 is a diagram showing the statuses of a critical load setting table, a communication channel load table, an assigned communication channel table, and a communication channel assignment status table after communication channel reassignment has been performed.

FIG. 15 is a view showing a flowchart for explaining an operation at the time of message transmission in the embodiment.

FIG. 16 is a view showing a flowchart for explaining an operation at the time of receiving a message in the embodiment.

[Explanation of symbols]

2a, 2b, 2c,..., Calculators, 3a, 3b, 3c,
… Processing unit, 4a, 4b, 4c,… communication processing unit
5 CPU for processing unit, 6 ROM for processing unit, 7 RAM for processing unit, 8 DMA controller, 9 CPU for communication processing unit, 10 ROM for communication processing unit, 11 RAM for communication processing unit, 12, 13, 14 ... communication unit (SCU), 1
5, 17, 19 ... line receiver, 16, 18, 20 ...
Line driver, 21: system bus, 22: local bus.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-125253 (JP, A) JP-A-2-193250 (JP, A) JP-A-4-79644 (JP, A) JP-A-4- 246748 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G06F 13/00 351-357 G06F 15/16-15/177 H04L 12/00

Claims (4)

(57) [Claims] When a plurality of computers are connected to a multiplexed communication path and a message is exchanged between system elements registered in the computer via the communication path, it is used according to the destination of the message. In a multiplex communication distributed processing system in which a communication path to be determined is determined and the message is exchanged by broadcast communication via the determined communication path, a communication path in which a communication path limit load value is set for each communication path. Road limit load value storage means, communication path load detection means for obtaining a load per specified time of a specified communication path of a received message and registering the same as a current load value, and an assigned communication path for registering a destination name and its assigned communication path An assigned communication path management means having a management table, searching the table for a communication path of a transmission destination, and determining which destination is registered for each communication path; When there is a request, the assigned communication path management means obtains a communication path of a transmission destination. When there is no corresponding communication path, a communication path with a smaller load than the communication path load detection means is assigned as a transmission communication path. Transmission channel assignment processing means for registering the destination name and the assigned communication channel in the assignment channel management table of the channel management means; and storing the communication channel limit load value when the transmission channel is assigned by the transmission channel assignment processing means. Communication path load confirmation processing means for fetching a limit load value and a current load value of the communication path from the means and the communication path load detection means to determine whether or not the current load value exceeds the limit load value; When it is determined that the current load value of the communication path assigned by the communication path load detection means exceeds the limit load value by the road load confirmation processing means, the allocation communication path management means grasps the current load value. Communication path assignment changing means for reassigning a part of the destination name group assigned to the communication path to a different communication path, wherein the transmission path assignment processing means assigns the transmission path assignment processing means or When the current load value of the transmission channel reallocated by the communication channel allocation changing means is determined not to exceed the limit load value, a transmission request message is transmitted to the allocated communication channel. Communication distributed processing system. 2. The multiplex communication distributed processing system according to claim 1, wherein each computer is provided with a communication frequency management means for counting the number of communication times of a communication path, and detected by a communication path load detection means by a communication path load confirmation processing means. If it is determined that the current load value of a given communication path has exceeded the limit load value of the communication path set in the limit load value storage means, the current communication number counted by the communication number management means is determined. A message consisting of a predetermined number is broadcast to all computers connected to the communication path, and when the communication count management means of all the computers detects that the notified communication count has been reached, the specified allocation change is performed. A multiplex communication distributed processing system characterized in that name groups are simultaneously changed in assignment. 3. The multiplex communication distributed processing system according to claim 1, wherein the assigned communication path management means manages the frequency of use for each message destination name, so that a certain communication path detected by the communication path load detection means is managed. When the current load value exceeds the limit load value of the communication path set by the limit load value storage means, the communication path allocation change means is assigned the destination name group assigned to the communication path ascertained by the assigned communication path management means. A distributed communication system, wherein a part of the data is distributed to the corresponding communication paths according to the use frequency of each destination name and the load of the communication path detected by the communication path load detecting means. 4. The multiplex communication distributed processing system according to claim 1, wherein the current load value detected by the communication path load detection means of all communication paths exceeds the limit load value set in the limit load value storage means. A distributed communication processing system, wherein the communication path allocation changing means does not change the assignment of the message destination name.