JP3933134B2 - Communications system - Google Patents

Description

  The present invention relates to a communication system that performs packet communication.

  A communication system in which a plurality of electronic computers communicate via an exchange network is known. The communication system (the communication system of the first conventional example) includes an exchange network and a plurality of electronic computers, and each of the plurality of electronic computers includes a communication device connected to the exchange network and an arithmetic device that performs an operation. A transmission buffer and a reception buffer. In the communication system of the first conventional example, as the communication processing, the arithmetic device does not directly transfer data, but the communication device performs data transfer according to a command from a process provided in the arithmetic device. To reduce the load. The communication system of the first conventional example is used as a parallel computer system.

However, the communication system of the first conventional example has the following problems.
When the transmission buffer and the reception buffer are single, as a result of communication performed by the communication device, subsequent reception data is discarded due to the reception buffer being full. The reception buffer full means that the length of data (reception data) included in the packet (reception packet) from the partner computer exceeds the reception buffer length (the length of data that the reception buffer can hold). Represents that.
When a plurality of processes provided in an arithmetic device simultaneously communicate using the same communication device, transmission data is copied to the transmission buffer of the communication device at the time of transmission, and received data is received from the reception buffer of the communication device at the time of reception. Since copying is performed to the reception buffer, overhead caused by copying twice occurs.

  In order to solve the problem of the communication system of the first conventional example, there is known a communication system that performs so-called zero copy communication (communication of the second conventional example) in which a process communicates without copying a buffer. The communication system of the second conventional example reduces overhead. In the communication system of the second conventional example, the communication device includes a transmission buffer and a reception buffer for each process. A process using the communication device notifies the communication device of a pointer to the transmission data, and the communication device extracts the data from the pointer notified from the process and transmits the data to the switching network without copying. The communication device that has received the data from the exchange network writes the data in the reception buffer that has been notified in advance by the process. Thereby, in the communication system of the second conventional example, it is possible to avoid the overhead caused by copying from the reception buffer dedicated to the communication device to the reception buffer of the process at the time of reception. Registration (preparation) of the reception buffer to the communication device is called issuance of a reception command, and a reception command is issued to the communication device each time a process newly waits for reception of data. When the reception command is issued, the communication device can use the reception buffer.

Techniques related to the conventional communication system including the communication system of the first conventional example and the communication system of the second conventional example are disclosed in JP-A-8-180001 (Patent Document 1) and JP-A-2002-229963 (Patent Document). 2), JP-A-4-116747 (Patent Document 3), JP-A 2002-207676 (Patent Document 4), JP-A 2000-322309 (Patent Document 5), JP-A-2001-282707 ( Patent Document 6) and Japanese Patent Laid-Open No. 9-270821 (Patent Document 7).
In particular, in the communication method described in Patent Document 1 (third conventional communication system), a process instructs a communication device to transfer data, and data is directly written from a process transmission buffer to a destination process reception buffer. An apparatus is disclosed. The destination process is a process of a destination computer that is a partner electronic computer.
As shown in Patent Document 1, the communication system of the third conventional example performs zero copy communication. In the communication system of the third conventional example, the transmitting process registers the transmission buffer in the communication device, the receiving process registers the reception buffer in the communication device, and the communication device transfers the data directly from the transmission buffer to the receiving buffer. By doing so, the communication time is shortened.

However, in the communication system of the third conventional example, it is necessary that the communication partner (destination computer) of the data transfer always defines the processing of the reception buffer or the reception packet, and the communication is performed between the processes that communicate in advance. It is necessary to prepare the processing on the receiving side by the next data transfer.
In addition, the operation of a communication apparatus using a general MPI (Message Passing Interface) library and having a data transfer function for directly writing to a communication partner's memory is as follows.
A control communication line is opened between processes (step 1).
A transmission-side process (transmission process) of a transmission source electronic computer (transmission source computer) sends a transmission request for transmitting transmission data from the communication device via a control communication line (destination computer). To the process on the receiving side (reception process) (step 2).
The reception process of the destination computer confirms the transmission request received by the communication device, and registers the reception buffer in the communication device (issues a reception command) (step 3).
The reception process of the destination computer notifies the transmission process of the transmission source computer of the reception preparation completion notification from the communication device via the control communication line (step 4).
The transmission process of the transmission source computer confirms the reception preparation completion notification received by the communication device and transfers the data (step 5).
As shown in steps 1 to 5, in the communication system of the third conventional example, the reception process of the destination computer uses the reception buffer so that data transfer is not performed when the reception buffer of the destination computer is unregistered. In order to prepare, actual data transfer is performed after communication other than data transfer (transmission request, reception preparation completion notification).

In the conventional communication system (the communication system of the second conventional example, the communication system of the third conventional example), before the transmission source computer starts data transfer, the reception process of the destination computer sets the reception buffer to the communication device. Must register. In order to register the reception buffer of the destination computer in the communication device in advance, the reception process of the destination computer issues a reception command to the communication device in advance. In order to issue a reception command in advance, it is necessary to prepare (register) a reception buffer before performing data transfer (data communication) between the transmission process of the source computer and the reception process of the destination computer. Control communication must take place.
As pre-control communication, a dedicated control buffer is provided in the source computer and destination computer, and the source computer and destination computer are synchronized with each other via communication via the control buffer, before the source computer sends data. In general, the reception process of the destination computer issues a reception command. That is, by the prior control communication, the source computer makes a request for preparing (registering) the reception buffer of the destination computer to the destination computer, and after the reception process of the destination computer prepares the reception buffer, Make a request to the sending computer. As described above, in the conventional communication system, since the prior control communication is performed before the data transfer (from the start of the data transfer to the completion), the latency from the start of the prior control communication to the completion of the data transfer (execution) Time) There is a problem that the latency from the start to the completion of data transfer increases.

JP-A-8-180001 JP 2002-229963 A JP-A-4-116747 JP 2002-207676 A JP 2000-322309 A JP 2001-282707 A JP-A-9-270821

Despite the rapid improvement in computing performance of computers, the improvement in communication performance between computers is slow, so the computing performance of computers in a system consisting of multiple computers and communicating with each other. Prior to this, the communication speed becomes a bottleneck, which often limits system performance. In particular, when computation processing is distributed to multiple computers and operating in synchronization with each other, computation processing performance cannot be performed until data is transmitted to the other party and the other computer receives the data. Decreases. That is, the latency, which is the time until communication reaches the other party, has a great influence on the computing performance of the system.
Therefore, in order to improve the system performance, it is necessary to shorten the communication latency because the computer executes the arithmetic processing for a longer time.
Furthermore, since the time for prior communication for confirmation of communication between a plurality of communicating devices and reception completion confirmation communication is large, it is necessary to delete communication other than prior communication other than data communication, such as reception completion confirmation.
An object of the present invention is to reduce the latency of a communication system by providing a communication system that can reduce the number of times of prior control communication or perform data transfer without performing the control at all.

  Hereinafter, means for solving the problem will be described using the numbers and symbols used in [Best Mode for Carrying Out the Invention]. These numbers and symbols are added to clarify the correspondence between the description of [Claims] and the description of [Best Mode for Carrying Out the Invention]. It should not be used to interpret the technical scope of the invention described in “

The communication system of the present invention comprises a first electronic computer and a second electronic computer connected to a network. The network corresponds to the switching network (400) described in the embodiment. The first electronic computer is, for example, the electronic computer (100-2) described in the embodiment, and the first electronic computer is, for example, the electronic computer (100-1) described in the embodiment.
The electronic computer (100-1) and the electronic computer (100-2) include a communication device (300), an arithmetic device (110), a reception command holding unit (212), a reception buffer (222), a holding buffer, It has. The holding buffer is a remote command FIFO (213) described in the embodiment. The arithmetic unit (110) includes a reception process (111). The reception command holding unit is a reception command FIFO (212) described in the embodiment. The reception process (111) issues a reception command (510) and registers it in the reception command FIFO (212).
The communication device (300) of the electronic computer (100-2) includes a first reception processing unit, a second reception processing unit, and a transmission processing unit. The first reception processing unit, the second reception processing unit, and the transmission processing unit are a context processing unit (341) described in the embodiment.
The electronic computer (100-1) transmits a packet including data to the electronic computer (100-) regardless of whether or not the reception command (510) is registered in the reception command FIFO (212) of the electronic computer (100-2). Transfer to 2). The packet is a data transmission packet (600) described in the embodiment.

When the reception command (510) is registered in the reception command FIFO (212) of the electronic computer (100-2) and the electronic computer (100-2) receives the data transmission packet (600), the electronic computer ( The context processing unit (341) of 100-2) writes the data of the data transmission packet (600) in the reception buffer (222).
As described above, according to the communication system of the present invention, the electronic computer (100-1) does not perform pre-control communication as described in the prior art on the electronic computer (100-2). The data transmission packet (600) can be transferred (data transfer can be performed).
According to the communication system of the present invention, since the electronic computer (100-1) performs data transfer without performing pre-control communication, the reception command (510) is the reception command FIFO (212) of the electronic computer (100-2). , The latency (execution time) from the start to the completion of the data transfer is the latency (execution time) from the start of the pre-control communication as described in the prior art to the completion of the data transfer. Less than.

If the electronic computer (100-2) receives the data transmission packet (600) when the reception command (510) is not registered in the reception command FIFO (212) of the electronic computer (100-2), the electronic computer ( The context processing unit (341) of 100-2) transmits an interruption request (610) for interrupting the transfer of the data transmission packet (600) to the electronic computer (100-1) and also transmits the data transmission packet (600). The transfer information regarding is registered in the remote command FIFO (213). The transfer information is a remote command (640) described in the embodiment, and the remote command (640) describes a part of the header of the data transmission packet (600). The interruption request is an interruption request packet (610) described in the embodiment. The computer (100-1) that has received the suspension request suspends the transfer of the data transmission packet (600) in response to the suspension request packet (610) from the computer (100-2).
As described above, according to the communication system of the present invention, useless data transfer that cannot be received by the electronic computer (100-2) can be prevented at an early stage, and useless data flowing through the exchange network (400) can be reduced.

When the reception command (510) issued next by the reception process (111) of the electronic computer (100-2) is registered in the reception command FIFO (212) of the electronic computer (100-2), the electronic computer ( 100-2) receives the data transmission packet (600), the context processing unit (341) of the electronic computer (100-2) refers to the remote command (640) registered in the remote command FIFO (213). Then, a restart request for restarting the transfer of the interrupted data transmission packet (600) is transmitted to the electronic computer (100-1). The restart request is a restart request packet (630) described in the embodiment. The computer (100-1) that has received the restart request packet sends a data transmission packet (600) to the electronic computer (100-2) in response to the restart request packet (630) from the computer (100-2). Transfer is resumed (data transfer is performed).
As described above, according to the communication system of the present invention, the electronic computer (100-1) only needs to transfer only data that cannot be received by the electronic computer (100-2) again. On the other hand, the data transmission packet (600) can be transferred (data transfer can be performed) without performing the prior control communication as described in the prior art.

The communication device (300) of the electronic computer (100-2) further includes a third reception processing unit. The third reception processing unit is the context processing unit (341).
When the electronic computer (100-2) receives the data transmission packet (600), the reception buffer (222) holds the data length of the data transmission packet (600) written to the reception buffer (222). When the data length of the data that can be transmitted exceeds the data length, the context processing unit (341) of the electronic computer (100-2) transmits a suspend request packet (610) to the electronic computer (100-1), and at the same time a remote command (640). Is registered in the remote command FIFO (213) of the electronic computer (100-2).
The remote command (640) and the restart request packet (630) are the data length (received) of the data written in the reception buffer (222) in the data transmission packet (600) from the electronic computer (100-1). When the data length is included, the restart request packet (630) is data other than the data written in the reception buffer (222) among the data transmission packet (600) from the electronic computer (100-1). This is information (packet) for requesting the transfer.
According to the communication system of the present invention, the electronic computer (100-1) refers to the received data length included in the restart request packet (630), and stores the data previously transferred in the data transmission packet (600). Of the data length, data having a data length other than the received data length (remaining data) is transferred to the electronic computer (100-2). According to the communication system of the present invention that requests transmission of only unreceived remaining data, the data transfer time from the electronic computer (100-1) to the electronic computer (100-2) is shortened compared to the case where all data is retransmitted. it can.

  In the communication system of the present invention, packets can be transferred without performing prior control communication as described in the prior art, so that the latency (execution time) from the start to the completion of data transfer is This is less than the latency (execution time) from the start of pre-control communication as described in the technology to the completion of data transfer.

FIG. 1 is a block diagram showing a configuration of a communication system according to the present invention. The communication system of the present invention includes a plurality of electronic computers (computers) and an exchange network 400 that is a network. A plurality of electronic computers are connected to the exchange network 400. A plurality of electronic computers are assumed to be electronic computers 100-1, 100-2, and 100-3.
The electronic computers 100-1, 100-2, and 100-3 include an arithmetic device 110 that performs arithmetic operations, a control device 120, a main storage device 200, and a communication device 300. An example of the arithmetic device 110 is a CPU (Central Processing Unit). The control device 120 functions as an interface for connecting the arithmetic device 110, the main storage device 200, and the communication device 300. The main storage device 200 holds data, instructions, and a computer number that identifies an electronic computer. The communication device 300 performs communication via the switching network 400 according to an instruction from the arithmetic device 110.
The configurations of the electronic computers 100-1, 100-2, and 100-3 are the same.

  In the communication system of the present invention, the transmission source computer (for example, the electronic computer 100-1) does not perform the prior control communication as described in the prior art with respect to the destination computer (for example, the electronic computer 100-2). , Packets can be transferred (data transfer can be performed). As a result, the latency (execution time) from the start to the completion of data transfer is lower than the latency (execution time) from the start of pre-control communication as described in the prior art to the completion of data transfer. . Embodiments of a communication system according to the present invention will be described below with reference to the accompanying drawings.

FIG. 2 is a block diagram showing the configuration of the communication device 300 of the electronic computers 100-1, 100-2, 100-3 in the communication system of the present invention.
The communication apparatus 300 includes a transmission unit 320, a reception unit 340, and a memory control unit 310. The memory control unit 310 transfers the memory access from the transmission unit 320 and the reception unit 340 to the control device 120, and returns the response of the memory access to the transmission unit 320 and the reception unit 340, respectively, via the control device 120. Mediates access to the communication device 300 from the arithmetic device 110. The transmission unit 320 generates a packet in response to a communication command execution instruction from the arithmetic device 110 via the memory control unit 310, and transmits the packet to the switching network 400. The receiving unit 340 receives a packet from the switching network 400 and processes the received packet according to the received packet.

The transmission unit 320 of the communication device 300 will be described. The transmission unit 320 includes an instruction processing unit 322 and a packet transmission unit 321. The instruction processing unit 322 includes a register 322 ′ (described later).
The instruction processing unit 322 extracts and analyzes a transmission command from the main storage device 200, receives a control packet (transmission interruption request packet, data request packet, reception packet) from the reception unit 340, and processes the transmission command.
The packet transmission unit 321 generates a data transmission packet based on the instruction from the command processing unit 322 and the transmission data received from the memory control unit 310 and transmits the data transmission packet to the switching network 400.

The receiving unit 340 of the communication device 300 will be described. The receiving unit 340 includes a packet receiving unit 342 and a context processing unit 341. The context processing unit 341 includes a register 341 ′ (described later).
When receiving a received packet including received data from the switching network 400, the packet receiving unit 342 notifies the context processing unit 341 that the data packet has been received. The packet receiving unit 342 receives an instruction to write received data in the received packet from the context processing unit 341, and writes the received data to the main storage device 200.
When the packet receiving unit 342 receives a control packet of any one of the transmission interruption request packet, the data request packet, and the reception packet from the switching network 400, the received packet is transferred to the context processing unit 341.
After receiving the data packet reception notification from the packet receiving unit 342, the context processing unit 341 reads a context (described later) corresponding to the received packet from the main storage device 200. The context processing unit 341 instructs the packet reception unit 322 to write the received data in the received packet to the main storage device 200 in accordance with the context read from the main storage device 200, and updates the main memory to update the context. Processing to write back the context to the device 200 is performed.
When the context processing unit 341 receives a control packet from the packet receiving unit 342, the context processing unit 341 transfers the control packet to the instruction processing unit 322.

FIG. 3 is a block diagram showing the configuration of the arithmetic unit 110 of the electronic computers 100-1, 100-2, 100-3 in the communication system of the present invention.
The arithmetic device 110 includes a plurality of processes to be executed by the arithmetic device 110 and driver software 113 for the communication device. There are N processes, which are arbitrary numbers different for each computer that is a computer program that transmits or receives data. When transmitting data via the communication device 300, the process is called a transmission process, and when receiving data via the communication device, the process is called a reception process. May be referred to as a sending process or a receiving process.
The driver software 113 has 1 to N unique connection numbers. The 1 to N connection numbers are identification numbers for the process 111 to communicate, and the 1 to N connection numbers are referred to as connection numbers “1” to “N”.
The communication device driver software 113 gives (sets) the connection numbers “1” to “N” to the process 111 at the initial stage. The process 111 having the connection number “1” to the process 111 having the connection number “N” are referred to as processes 111-1, 111-2,..., 111-N, respectively.

  The sending process 111-J (J = 1, 2,..., N) of the source computer and the receiving process 111-K (K = 1, 2,..., N) of the destination computer are the process 111-J of the sending computer. Transmits to the destination connection number “K” together with the transmission data using the communication device 300, the communication device 300 (reception unit 340) of the destination computer uses the destination connection number “K” from the source computer to send the destination computer. The receiving process 111-K is specified (described later). The transmission source computer is one of the electronic computers 100-1, 100-2, and 100-3, and the destination computer is the transmission source of the electronic computers 100-1, 100-2, and 100-3. It is one electronic computer other than the computer.

FIG. 4 is a block diagram showing the configuration of the main storage device 200 of the computers 100-1, 100-2, 100-3 in the communication system of the present invention.
The main storage device 200 stores a transmission command FIFO 211, a reception command FIFO 212, a remote command FIFO 213, a context table 201, a transmission buffer 221, a reception buffer 222, a transfer length register 231, and a transfer address register 232. Has been.

The transmission buffer 221 includes transmission buffers 221-1 to 221-N specific to each process. A certain process 111-J (J is arbitrary) can use an arbitrary address in the process address space as a transmission buffer and can hold a plurality of transmission buffers. The following will be described assuming that the transmission buffer of J is 221-J.
The reception buffer 222 includes reception buffers 222-1 to 222-N specific to each process. A certain process 111-J (J is arbitrary) can use any address in the address space of the process as a reception buffer and can hold a plurality of reception buffers. The following will be described assuming that the reception buffer of J is 222-J.
The transfer length register 231 includes unique transfer length registers 231-1 to 231-N.
The transfer address register 232 includes unique transfer address registers 232-1 to 232-N.

The transmission command FIFO 211 includes transmission commands FIFO 211-1 to 211-N specific to each process. The transmission command FIFO 211-J (J = 1, 2,..., N) is control data having a FIFO (First In First Out) structure used by the process 111-J. The process 111 -J transmits the transmission data using the communication device 300. The process 111-J registers the transmission data in the transmission buffer 221-J, and issues a transmission command for the communication device 300 to transmit the transmission data (registers in the transmission command FIFO 211-J). The address of the transmission buffer 221-J is specified when the process 111-J issues a transmission command (when the transmission command is registered in the transmission command FIFO 211-J).
The reception instruction FIFO 212 includes reception instructions FIFO 212-1 to 212-N specific to each process. The reception command FIFO 212-J (J = 1, 2,..., N) is FIFO structure control data used by the process 111-J. Process 111 -J receives received data using communication device 300. The process 111-J issues a reception command for the communication device 300 to receive the received data (registers in the reception command FIFO 212-J). When the process 111-J issues a reception command, the reception buffer 222-J is registered (prepared) in the communication device 300, and the communication device 300 can use the reception buffer 222-J. The address of the reception buffer 222-J is specified when the process 111-J issues a reception command (when the reception command is registered in the reception command FIFO 212-J).

The remote command FIFO 213 includes remote command FIFOs 213-1 to 213-N. The remote command FIFO 213-J (J = 1, 2,..., N) is FIFO structure control data used by the context processing unit 341 in the communication apparatus 300, and is a remote computer (described later) via the switching network 400. This is a holding buffer that temporarily holds communication from. The communication device 300 uses one remote command FIFO 213-J for each connection number.
The context table 201 includes context tables 201-1 to 201-N specific to each process. The context table 201-J (J = 1, 2,..., N) is a control table that is used by the context processing unit 341 and holds the communication state with the remote computer via the switching network 400. The communication device 300 uses one context (described later) for each connection number.

  Here, the communication device 300 further includes a communication device dedicated memory (not shown), and the data structure may be stored in the communication device dedicated memory. The data structure includes control data (transmission instruction FIFO 211, reception instruction FIFO 212), buffer {transmission buffer 221, reception buffer 222, remote instruction FIFO 213 (holding buffer)}, context table 201, registers (transfer length register 231, transfer address register 232). ). Since the communication device 300 includes the communication device dedicated memory, the communication device 300 can access the communication device dedicated memory at high speed. By providing the above data structure on a communication device dedicated memory that can be accessed at high speed, the latency and transfer bandwidth of data transfer are improved. However, in order to enable the arithmetic device 110 to directly access the communication device dedicated memory, the communication device dedicated memory needs to be accessible as a part of the address space used by the arithmetic device 110.

FIG. 5 shows a transmission command 500 in the communication system of the present invention. In order for the arithmetic unit 110 (process 111-J) to transmit the transmission data, the process 111-J writes the transmission command 500 to the main storage device 200 (transmission command FIFO 211-J), and the command processing unit 322 of the transmission unit 320 Read the transmission command 500.
The transmission command 500 includes a transmission type column 501 indicating a transmission command, a destination computer number column 502 indicating a destination computer number, a connection number column 503 indicating a destination connection number, and a transmission indicating a start address of the transmission buffer. It consists of a buffer start address column 504 and a transfer length column 505 indicating the length of data to be transmitted.

  When the process 111-J registers the transmission command 500 in the transmission command FIFO 211-J, the transmission type indicating that it is a transmission command is written in the transmission type column 501 by the process 111-J. In the destination computer number field 502, the destination computer number is written as a computer number for identifying the destination computer. In the connection number column 503, the connection number for identifying the destination process in the destination computer is written. In the transmission buffer start address column 504, a transmission buffer start address that is the head address of the transmission buffer 221-J that holds transmission data is written. In the transfer length column 505, a transfer length that is a data length indicating the length of the transmission data is written.

The management of the transmission command FIFO 211-J will be described.
The register 322 ′ in the command processing unit 322 of the communication device 300 can register M transmission commands for each of the transmission commands FIFO 211-1 to 211-N on the main storage device 200 for each connection number. This is a ring buffer FIFO, and each instruction is identified by an instruction number from 0 to M-1. The M is the maximum number of instructions for each of the transmission instructions FIFO 211-1 to 211-N. The write pointers of the transmission command FIFOs 211-1 to 211 -N indicate the command number at which each of the processes 111-1 to 111 -N registers a transmission command next, and the process 111 registers one transmission command 500. Add +1 each time. However, if the value of the write pointer exceeds M when +1 is added to the write pointer, the write pointer wraps around and is set to “1”. The read pointer of the transmission command FIFO 211-1 to 211 -N indicates the command number of the transmission command 500 to be executed next by the command processing unit 322, and the command processing unit 322 receives a command from the transmission command FIFO 211-1 to 211 -N. +1 is added each time. However, if the value of the read pointer exceeds M when +1 is added to the read pointer, the read pointer wraps around and is set to “1”.
The driver software 113 for the communication device registers the start address of the transmission command FIFOs 211-1 to 211-N on the main storage device 200 and the maximum number of commands in the transmission command FIFO 211 in the register in the command processing unit 322 at the initial setting. It is preset to 322 ′.

Each time the transmission process 111-1 to 111 -N adds (registers) one transmission command 500 to the main storage device 200 (transmission command FIFO 211-1 to 211 -N), the transmission command FIFO 211 in the command processing unit 322. Add 1 to the write pointer of −1 to 211-N.
The instruction processing unit 322 compares the write pointer of the transmission instruction FIFO 211-J (1, 2,..., N) with the read pointer of the transmission instruction FIFO 211-J. If there is a difference as a result of the comparison, the instruction processing unit 322 determines that the transmission instruction 500 has been added, and the transmission instruction 500 having the instruction number indicated by the read point of the transmission instruction FIFO 211-J from the start address of the transmission instruction FIFO 211-J. Are extracted from the transmission command FIFO 211 -J on the main storage device 200 via the control device 120 and the memory control unit 310, and the transmission command 500 is executed.
The instruction processing unit 322 adds 1 to the read pointer of the transmission instruction FIFO 211 -J in the instruction processing unit 322 every time one transmission instruction 500 is executed. When the instruction processing unit 322 adds the read pointer of the transmission instruction FIFO 211-J by 1, even when the read pointer of the transmission instruction FIFO 211-J and the write pointer of the transmission instruction FIFO 211-J are different, That is, when there is a difference, the next transmission command 500 is extracted from the transmission command FIFO 211 -J on the main storage device 200 via the control device 120 and the memory control unit 310 by the read point of the transmission command FIFO 211 -J. The transmission command 500 is executed. The transmission command extraction and execution are executed until there is no difference between the read pointer of the transmission command FIFO 211-J and the transmission command FIFO write pointer.

  The control device 120 writes a transmission command 500, writes transmission data into the main storage device 200 from the processes 111-1 to 111-N in the arithmetic device 110, and the main storage device 200 by each process on the arithmetic device 110. Writing and reading to the main storage device 200, reading transmission commands from the transmission unit 320, reading transmission data, and writing and reading requests to the main storage device 200 from the reception unit 340. Perform a read.

FIG. 6 shows a data transmission packet 600 in the communication system of the present invention. In order for the transmission process 111 -J in the computing device 110 to transmit transmission data, the packet transmission unit 321 of the transmission unit 320 generates a data transmission packet 600 including the transmission data and transmits it to the switching network 400.
The command processing unit 322 extracts the transmission command 500 from the transmission command FIFO 211 -J on the main storage device 200 and transmits it from the transmission buffer 221 -J by the transmission buffer start address written in the transmission buffer start address field 504 of the transmission command 500. An instruction to read the data and transfer it to the packet transmission unit 321 is issued to the memory control unit 310. Receiving the instruction, the memory control unit 310 takes out transmission data from the transmission buffer 221 -J on the main storage device 200 via the control device 120 and transfers it to the packet transmission unit 321.
The packet transmission unit 321 divides the transmission data received from the memory control unit 310 into predetermined packet (data transmission packet 600) lengths, and adds a continuous packet number to each data transmission packet 600. The packet number is the 0th packet number for the first packet of one transmission command, and the subsequent 1, 2, 3,..., Nth packet numbers.

The data transmission packet 600 includes a transmission type column 601, a destination computer number column 602, a transmission source computer number column 603, a connection number column 604, a transmission command number column 605, a packet number column 606, and a data length column. 607 and a data column 607 are included.
A portion other than the data column 608 of the data transmission packet 600 is called a packet header and is used for packet control.

  When the data transmission packet 600 is generated, the packet transmission unit 321 writes a transmission type indicating that the data transmission packet 600 is in the transmission type column 601. In the destination computer number column 602, a destination computer number for identifying the destination computer is written. In the transmission source computer number column 603, a transmission source computer number is written as a computer number for identifying the transmission source computer. In the connection number column 604, a connection number for identifying a destination process in the destination computer is written. In the transmission command number column 605, a transmission command number for identifying each of the transmission commands simultaneously transmitting packets to the same destination computer is written. In the packet number column 606, packet numbers for identifying a plurality of packets generated by the same transmission command are written. A data length indicating the length of data incorporated in the data transmission packet 600 is written in the data length column 607. In the data column 608, transmission data read from the transmission buffer 221-J is written.

Here, the transmission command number is a specific transmission command 500 (a transmission command when the data transmission packet 600 is now generated) from a transmission command 500 that is sequentially executed after being registered in the reception commands FIFO 212-1 to 212-N. 500), and a number added by the instruction processing unit 322 for each instruction. The instruction processing unit 322 holds the transmission instruction number of the next instruction in the register 322 ′, and when a transmission instruction number is newly extracted, the transmission instruction number of the next instruction is incremented by 1, thereby different transmission instructions for each transmission instruction. Add a number.
The packet number is data generated by the same transmission command 500 (the above-mentioned specific transmission command 500) when the data (transmission data) is divided into predetermined packet (data transmission packet 600) lengths. This is a number indicating which data transmission packet 600 in the transmission packet 600 is.
An example of packet division is shown below.
In the packet division performed by the packet transmission unit 321 (division of the data transmission packet 600), when the maximum packet length is 1000 bytes and the transfer length of the transmission command 500 is 3500 bytes, the packet transmission unit 321 includes three 1000 bytes. A data transmission packet 600 having data and a data transmission packet 600 having one 500-byte data are generated and transmitted to the switching network 400.

FIG. 7 shows a reception command 510 in the communication system of the present invention. In order for the arithmetic unit 110 (process 111-J) to receive the received data, the process 111-J writes the reception command 510 to the main storage device 200 (reception command FIFO 212-J), and the context processing unit 341 of the reception unit 340 Read reception instruction 510.
The reception command 510 includes a reception type column 511, a transmission source computer number column 512, a connection number column 513, a reception buffer start address column 514, and a reception buffer length column 515.
When the process 111-J registers the reception command 510 in the reception command FIFO, the reception type indicating that it is a reception command is written in the reception type column 511. In the transmission source computer number column 512, a transmission source computer number for identifying the transmission source computer is written. In the connection number column 513, a connection number for identifying the reception process 111-J is written. In the reception buffer start address column 514, the head address (reception buffer start address) of the reception buffer 222-J that holds the received reception data is written. In the reception buffer length column 515, the reception buffer length indicating the length of data that can be held by the reception buffer 222-J is written.

The management of the reception command FIFO 212-J will be described.
The register 341 ′ in the context processing unit 341 of the communication device 300 stores the start address of the reception command FIFOs 212-1 to 212 -N on the main storage device 200 and the reception command FIFOs 212-1 to 212 -N for each connection number. The read pointer and the write pointers of the reception instructions FIFOs 212-1 to 212-N are held. The number of instructions that can be registered in each reception instruction FIFO is M, and each entry of the reception instruction FIFO has a number instruction in which the first entry instruction is 0, the next is 1, ..., and the last is M-1. Append.
The write pointers of the reception instruction FIFOs 212-1 to 212-N indicate instruction numbers that the arithmetic device 110 (processes 111-1 to 111-N) registers next. The read pointers of the reception instruction FIFOs 212-1 to 212 -N indicate the instruction number to be executed next by the context processing unit 341.
The driver software 113 for the communication device uses a register in the context processing unit 341 at the initial setting of the start address of the reception command FIFOs 212-1 to 212 -N on the main storage device 200 and the maximum number of commands in the reception command FIFO 212. It is preset to 341 ′. Each time the context processing unit 341 processes one reception instruction, the read pointers of the reception instructions FIFOs 212-1 to 212 -N are incremented by one, and the write pointers of the reception instructions FIFOs 212-1 to 212 -N are received. Each time the processes 111-1 to 111-N register one reception command, one is added. The read pointer and write pointer of the reception instruction FIFOs 212-1 to 212 -N become “0” when the last instruction number of the reception instruction FIFO is exceeded when 1 is added.

The context processing unit 341 compares the write pointer of the reception instruction FIFO 212-J (1, 2,..., N) with the read pointer of the reception instruction FIFO 212-J. If there is a difference as a result of the comparison, the context processing unit 341 determines that the reception instruction 510 has been added, and the main instruction is stored in the reception instruction 510 indicated by the read point of the reception instruction FIFO 212-J from the start address of the reception instruction FIFO 212-J. The reception instruction FIFO 212-J on the apparatus 200 is taken out via the control device 120 and the memory control unit 310, and the reception instruction 510 is executed.
Each time the context processing unit 341 executes one reception command 510, the context processing unit 341 adds 1 to the read pointer of the reception command FIFO 212-J in the context processing unit 241. The context processing unit 341 adds the read pointer of the reception instruction FIFO 212-J by 1 and the read pointer of the reception instruction FIFO 212-J and the write pointer of the reception instruction FIFO 212-J are different from each other ( If there is a difference), the next reception instruction 510 is fetched from the reception instruction FIFO 212-J on the main storage device 200 via the control device 120 and the memory control unit 310 according to the read point of the reception instruction FIFO 212-J. A receive instruction 510 is executed. The received instruction fetch process is executed until there is no difference between the read pointer of the received instruction FIFO 212-J and the write pointer of the received instruction FIFO 212-J.

FIG. 8 shows a context 700 in the communication system of the present invention. The context 700 managed by the context processing unit 341 for determining the operation of the receiving unit 340 when the receiving unit 340 receives a packet from the switching network 400 will be described in detail.
A context 700 exists for each connection number. When the data transmission packet 600 is received by the packet reception unit 342, the context 700 is referred to by the value in the connection number column 604 in the data transmission packet 600 and is taken into the context processing unit 341. The context 700 includes a receiving command processing flag column 701, a transmission command number column 702, a final received packet number column 703, a received data length column 704 of a processing received reception command, a transmission interrupted flag 705, and a processing. A reception command column 710.
The in-process received command column 710 holds a part of the receive command 510 being processed by the receiving unit 340. The receive type column 711 of the in-process received command, the receive buffer start address column 712 of the in-process received command, and the processing A buffer length column 713 for a medium reception command.

The context 700 is stored in the context tables 201-1 to 201-N. The context 700 in the context table 201-J (J = 1, 2,..., N) is a context for the connection number “J”.
When the packet reception unit 342 receives the data transmission packet 600, the packet reception unit 342 transfers the packet header of the data transmission packet 600 to the context processing unit 341.
The context processing unit 341 that has received the packet header refers to the context table 201 -J by the connection number “J” described in the connection number column 604 in the packet header, and takes in the corresponding context 700.

Referring to FIG. 16, the packet receiving unit 342 receives the data transmission packet 600 from the switching network 400, transmits the packet header to the context processing unit 341, and details the processing after the context processing unit 341 captures the context 700. Explained.
Here, “unquestioned” in the figure means that the operation is not affected at all, and “sufficient” in the figure means that all data of the data transmission packet 600 received by the reception buffer 222-J is written. This means a case where there is a sufficient remaining reception buffer length. “Insufficient” in the drawing means that the remaining reception buffer length is sufficient to write all the data of the data transmission packet 600 received by the reception buffer 222-J. There is also a case where the reception buffer is full (or the reception buffer is full).

  Upon receiving the packet header, the context processing unit 341 receives the context status of the packet processing flag 701 (processing 701 in the figure) and the interrupted flag 705 (suspended 705 in the figure) in the context 700, and The processing of the context and packet is determined based on the presence / absence of the reception command corresponding to the packet connection number 604 and the state of the reception command with sufficient / insufficient remaining buffer length. Examples of the state include case names “Case A1”, “Case A2”, “Case R1”, “Case R2”, “Case R3”, and “Case D1” in the figure.

Case A1 indicates a case where the value of the packet processing flag 701 is “0” indicating non-processing, the reception command 510 corresponding to the packet exists, and the remaining reception buffer length is sufficient. In case A1, the context processing represents “creation”, and the packet processing represents “data processing”.
The remaining reception buffer length when the value of the packet processing flag 701 is “0” is the reception buffer length 515 in the reception command 510. The remaining reception buffer length when the value of the packet processing flag 701 is “1” is the reception buffer length 515 in the reception instruction 510 minus the received data length 704 of the processing instruction in the context 700. .
The initial value of the packet processing flag 701 is “0”, the packet processing flag 701 after initialization of the communication device 300 and the driver software 113 for the communication device is “0”, and transmission is performed. After the processing of all packets of the instruction is completed, the packet processing flag 701 is cleared to “0”.
In case A1, the context processing unit 341 extracts the first reception instruction 510 from the reception FIFO 212, registers the reception instruction 510 in processing in the context 700, and sets “1” indicating processing in the reception instruction processing flag 701. The transmission command number described in the transmission command number column 605 of the packet 600 is written in the write / transmission command number column 702, and the packet number described in the packet number column 606 of the packet 600 is written in the last received packet number column 703. Is written, the data length described in the data length column 607 of the packet 600 is written in the received data length column 704 of the receiving command being processed, and “0” indicating non-interruption is written in the transmission interrupted flag 705.

Case A2 shows a case where the value of the packet processing flag 701 is “1” indicating that processing is in progress, the value of the transmission interrupted flag 705 is “0” indicating non-interruption, and the remaining reception buffer length is sufficient. In case A2, the context processing represents “update”, and the packet processing represents “data processing”.
In case A2, the context processing unit 341 does not update the reception command processing flag 701 and the transmission command number column 702, and writes the packet number described in the packet number column 606 of the packet 600 in the last received packet number column 703. Then, “0” indicating non-interruption is written in the transmission interrupted flag 705.

  In cases A1 and A2, when the data length 607 of the packet 600 is not “0”, the received data length 704 of the receiving command in process in the context 700 is added to the receiving buffer start address 514 without the receiving command 510. When the address is transferred to the packet receiving unit 342, the data 608 in the packet is instructed to be written to the main storage device 200, and the data length 607 of the packet 600 is “0”, the final data of the transmission command The reception packet is transferred to the transmission unit 320, and the reception command processing flag 701 in the context 700 is cleared to “0”.

In case R1, the case where the value of the packet processing flag 701 is “0” indicating non-processing, the reception command 510 corresponding to the packet exists, and the remaining reception buffer length is insufficient (reception buffer full). Show. In the case of the case R1, the process of the context represents “create and interrupt”, and the process of the packet represents “create remote command”.
In case R1, the context processing unit 341 extracts the first reception instruction 510 from the reception FIFO 212, registers the reception instruction 510 in the context 700, and registers “1” indicating that processing is in progress in the reception instruction processing flag 701. The transmission command number described in the transmission command number column 605 of the packet 600 is written in the write / transmission command number column 702, and “0” indicating that no packet has been received is written in the last received packet number column 703. To write “0” in the received data length column 704 of the middle reception command, write “1” in the transmission interrupted flag 705, and notify the transmission unit 320 of the transmission source computer that the reception has been interrupted. Then, the interruption request packet is transferred to the transmission unit 320 of the own computer.

Case R2 shows a case where the value of the packet processing flag 701 is “0” indicating that processing is not in progress. In the case of the case R2, the process of the context represents “create and interrupt”, and the process of the packet represents “create remote command”.
In case R2, the context processing unit 341 writes “1” indicating that processing is in progress to the reception command processing flag 701, and the transmission command number described in the transmission command number column 605 of the packet 600 is stored in the transmission command number column 702. Write, “0” indicating that the packet has not been received is written in the last received packet number column 703, “0” is written in the received data length column 704 of the receiving command being processed, and the transmission interrupted flag 705 has been interrupted. A certain “1” is written, and an interruption request packet is transferred to the transmission unit 320 of the own computer in order to notify the transmission unit 320 of the transmission source computer that reception has been interrupted.

In case R3, the value of the packet processing flag 701 is “1” indicating that processing is in progress, the value of the transmission interrupted flag 705 is “0” indicating non-interruption, and the remaining reception buffer length is insufficient (reception buffer full). Indicates a case. In the case of the case R3, the process of the context represents “suspend”, and the process of the packet represents “create remote command”.
In case R3, the context processing unit 341 does not update the reception command processing flag 701, the transmission command number column 702, and the final reception packet number column 703, and writes “1” that has been interrupted to the transmission interrupted flag 705. In order to notify the transmission unit 320 of the transmission source computer that reception has been interrupted, the interruption request packet is transferred to the transmission unit 320 of the own computer.

  In cases R1, R2, and R3, the context processing unit 341 creates a remote command (described later) and registers it in the remote command FIFO for the connection number 604 of the packet.

Case D1 shows a case where the value of the packet processing flag 701 is “1” indicating that processing is in progress and the value of the transmission interrupted flag 705 is “1” indicating that the processing is interrupted. In case D1, the context processing represents “no update”, and the packet processing represents “discard”.
In case D1, the context processing unit 341 discards the packet 600.

  Next, an interruption request packet and an acceptance packet, which are reply packets sent back to the sending computer of the packet 600 in response to the data transmission packet 600 by the context processing unit 341 of the destination computer, will be described.

FIG. 9A shows an interruption request packet 610 in the communication system of the present invention.
The interruption request packet 610 includes an interruption request type field 611, a destination computer number field 612, a transmission source computer number field 613, a connection number field 614, and a transmission command number field 615.
When the context processing unit 341 generates the interruption request packet 610, the interruption request type indicating that transmission interruption is requested is written in the interruption request type column 611, and the destination computer number of the data transmission packet 600 is written in the destination computer number column 612. The destination computer number described in the column 602 is written, the source computer number described in the source computer number column 603 of the data transmission packet 600 is written in the source computer number column 613, and the data transmission is performed in the connection number column 614. The connection number described in the connection number column 604 of the packet 600 is written, and the transmission command number described in the transmission command number column 605 of the data transmission packet 600 is written in the transmission command number column 615.

Further, as another example of the interruption request packet, a method for generating an interruption request packet in the case where a received data length is added to the interruption request packet 610 and data is retransmitted from data interrupted when the transfer is resumed, which will be described later Is shown below.
The interruption request packet 610 includes the interruption request type field 611, the destination computer number field 612, the transmission source computer number field 613, the connection number field 614, the transmission command number field 615, and the received data length. It consists of a column 616. The context processing unit 341 calculates a residual reception buffer length that is a value obtained by subtracting the received data length 704 of the processing reception command from the buffer length 713 of the processing reception command of the context 700, and receives the packet received from the switching network 400 When the data length 607 of the packet is larger than the remaining reception buffer length, the reception buffer full is detected, and the data length described in the data length column 607 of the data transmission packet 600 is written in the reception data length column 616 of the interruption request packet 610 The interrupt request packet 610 notifies the data length of the data written in the reception buffer 222-J.

FIG. 10 shows an acceptance packet 620 in the communication system of the present invention.
When the context processing unit 341 receives the packet header from the packet receiving unit 342 that has received the data transmission packet 600, the context processing unit 341 connects the connection number in the packet header from the context tables 201-1 to 201-N of the main storage device 200. The context 700 corresponding to the connection number “J” described in the column 604 is extracted.
In the context 700, the reception command processing flag field 701 is not set with a reception command processing flag, and the transmission interrupted flag field 705 is not set with a transmission interrupted flag (it is “0”). When the reception command 510 is registered in the reception command FIFO 212-J corresponding to the connection number “J” described in the connection number column 604, the context processing unit 341 accepts it as a reply packet to the data transmission packet 600. The packet 620 is transmitted to the transmission source computer via the transmission unit 320 and a reception command write instruction is transmitted to the packet reception unit 342. The packet reception unit 342 writes the data (reception data) described in the data column 608 of the data transmission packet 600 in the reception buffer 222-J in response to the reception command write instruction.

The reception packet 620 includes a reception type column 621, a destination computer number column 621, a transmission source computer number column 623, a connection number column 624, and a transmission command number column 625.
The context processing unit 341 writes a reception type indicating that it is a reception packet in the reception type column 621, writes the destination computer number described in the destination computer number column 602 of the data transmission packet 600 in the destination computer number column 621, and sends In the former computer number column 623, the sender computer number described in the sender computer number column 603 of the data transmission packet 600 is written, and in the connection number column 624, it is written in the connection number column 604 of the data transmission packet 600. The connection number is written, and the transmission command number written in the transmission command number column 605 of the data transmission packet 600 is written in the transmission command number column 625 to generate a reception packet 620.

The management of the reception command FIFO 212-J when the reception command 510 is issued to the context processing unit 341 will be described.
When the reception process 111-J operating in the arithmetic unit 110 issues the reception command 510 to the context processing unit 341, the reception process 111-J receives the reception command FIFO 212-J on the main storage device 200 used by itself. The reception instruction 510 is added to the write pointer of the reception instruction FIFO 212-J (held by the register 341 ′) in the context processing unit 341, and the number of the reception instructions 510 added is added.
The context processing unit 341 compares the write pointer of the reception instruction FIFO 212-J with the read pointer of the reception instruction FIFO 212-J. If there is a difference as a result of the comparison, the context processing unit 341 determines that the reception instruction 510 has been added, and the context 700 corresponding to the connection number “J” is determined from the context tables 201-1 to 201-N of the main storage device 200. Take out.
When the received command processing flag in the received command processing flag column 701 of the context 700 is “1” and the transmission interrupted flag in the transmission interrupted flag column 705 is “0”, the context processing unit 341 Wait until data transmission packet 600 corresponding to reception command 510 is received.
On the other hand, when the transmission interrupted flag in the transmission interrupted flag column 705 is “1”, the context processing unit 341 receives a remote command (first remote command, first command from the remote command FIFO 213-J corresponding to the connection number “J”). 2 remote command), a resumption request packet (described later) is created, and a resumption request packet described later is transmitted to the switching network 400 via the transmission unit 320.

FIG. 11 (a) shows a remote command 640 in the communication system of the present invention. The context processing unit 341 generates a remote command 640 based on the packet header received from the packet receiving unit 342 and registers it in the remote command FIFO 213 on the main storage device 200.
The remote command 640 includes a remote command type column 641, a destination computer number column 642, a source computer number column 643, a connection number column 644, and a transmission command number column 645.
When the context processing unit 341 generates the remote command 640, the remote command type indicating that it is a remote command is written in the remote command type column 641, and the destination computer number column 602 of the data transmission packet 600 is written in the destination computer number column 642. Is written in the source computer number field 643, the source computer number described in the source computer number field 603 of the data transmission packet 600 is written, and the data transmission packet 600 is written in the connection number field 644. The connection number described in the connection number column 604 is written, and the transmission command number described in the transmission command number column 605 of the data transmission packet 600 is written in the transmission command number column 645.

  When the context processing unit 341 generates the remote command 640, the reception command 510 is registered in the reception command FIFO 212-J, but when the reception buffer 222-J is detected full, the context processing unit 341 displays As shown in (b), a received data length column 646 is added to the remote command 640. The context processing unit 341 writes the data length described in the data length column 607 of the data transmission packet 600 in the received data length column 646 as the received data length.

As described above, the communication device 300 uses the remote command FIFO 213-J (holding buffer) on the main storage device 200 for each connection number (see FIG. 4).
The register 341 ′ in the context processing unit 341 of the communication device 300 stores, for each connection number, a pointer to the start address of the remote command FIFOs 213-1 to 213 -N on the main storage device 200 and the remote command FIFOs 213-1 to 213. -N read pointers and remote instruction FIFOs 213-1 through 213-N are held. The write pointers of the remote instructions FIFOs 213-1 to 213 -N represent the number of remote instructions 640 (the number of instructions: 0, 1, 2,...) That the context processing unit 341 instructs itself. The write pointers of the remote instructions FIFOs 213-1 to 213 -N represent the number of remote instructions 640 executed by the context processing unit 341 (number of instructions: 0, 1, 2,...).
The driver software 113 for the communication device stores an initial value in advance in the register 341 ′ in the context processing unit 341 as a pointer to the top address of the remote command FIFOs 213-1 to 213-N on the main storage device 200 at the time of initial setting. The maximum number of instructions in the remote instruction FIFOs 213-1 to 213-N is set in advance in the register 341 ′. The driver software 113 for the communication device sets the read pointers of the remote instructions FIFOs 213-1 to 213-N and the write pointers of the remote instructions FIFOs 213-1 to 213-N to “0” at the time of the initial setting. The read pointer and write pointer of the remote instruction FIFOs 213-1 to 213-N become “0” when the maximum number of instructions is exceeded.

Each time the context processing unit 341 adds (registers) one remote command 640 to the main storage device 200 (remote command FIFOs 213-1 to 213-N), the remote command FIFOs 213-1 to 213- in the context processing unit 341 are added. Add 1 to the N write pointer.
The context processing unit 341 compares the write pointer of the remote instruction FIFO 213-J (1, 2,..., N) with the read pointer of the reception instruction FIFO 212-J. If there is a difference as a result of the comparison, the context processing unit 341 determines that the remote command 640 has been added, and the remote at a position advanced from the start address of the remote command FIFO 213-J by the number of read points of the remote command FIFO 213-J. The remote command 640 next to the command 640 is fetched from the remote command FIFO 213-J on the main storage device 200 via the control device 120 and the memory control unit 310, and the remote command 640 is executed.
Every time one remote command 640 is executed, the context processing unit 341 adds 1 to the read pointer of the remote command FIFO 213 -J in the context processing unit 241. The context processing unit 341 adds the read pointer of the remote instruction FIFO 213-J by 1 and the read pointer of the remote instruction FIFO 213-J is different from the write pointer of the remote instruction FIFO 213-J ( If there is a difference), the remote command FIFO 213-J reads the next remote command 640 from the remote command FIFO 213-J on the main storage device 200 via the control device 120 and the memory control unit 310. The remote command 640 is executed. The processing is executed until there is no difference between the read pointer of the remote instruction FIFO 213-J and the write pointer of the remote instruction FIFO 213-J.

  FIG. 12A shows a restart request packet 630 in the communication system of the present invention. The reception process 111-J operating on the arithmetic device 110 issues a reception command 510 to the context processing unit 341, and the context processing unit 341 is connected from the context tables 201-1 to 201-N of the main storage device 200. The context 700 corresponding to the number “J” is taken out. When the transmission suspended flag column 705 of the context 700 is “1”, the context processing unit 341 extracts the remote command 640 from the remote command FIFO 213 -J, and resume request packet 630 based on the remote command 640. And the restart request packet 630 is transmitted to the switching network 400 via the transmission unit 320.

The restart request packet 630 includes a restart request type column 631, a destination computer number 632, a source computer number column 633, a connection number column 634, and a transmission command number column 635.
When the context processing unit 341 generates the restart request packet 630, the context processing unit 341 writes the restart request type indicating the restart request in the restart request type column 631, and is described in the destination computer number 632 in the destination computer number column 642 of the remote command 640. The destination computer number is written, the source computer number described in the source computer number column 643 of the remote command 640 is written in the source computer number column 633, and the connection number column 644 of the remote command 640 is written in the connection number column 634. And the transmission command number described in the transmission command number column 645 of the remote command 640 is written in the transmission command number column 635.

  When the transfer is resumed when the transmission (transfer) is interrupted due to the reception buffer 222-J being full (when the resume request packet 630 is transmitted), the context processing unit 341 returns to FIG. As shown, a received data length column 636 is added to the resume request packet 630. The context processing unit 341 writes the received data length described in the received data length column 646 of the remote command 640 in the received data length column 636.

  Next, packet transmission execution processing, packet reception execution processing, and reception command execution processing will be described as operations of the communication system of the present invention. Here, the transmission source computer is the electronic computer 100-1, and the destination computer is the electronic computer 100-2.

FIG. 13 is a flowchart showing packet transmission execution processing (steps S1 to S13) which is the operation of the communication system of the present invention.
The transmission process 111-J on the arithmetic unit 110 of the electronic computer 100-1 writes (registers) the transmission command 500 in the main storage device 200 (transmission command FIFO 211-J), and the transmission unit 320 of the electronic computer 100-1 When the number of transmission instructions 500 is added to the write pointer of the transmission instruction FIFO 211-J (held by the register 322 ′) in the instruction processing unit 322, the transmission unit 320 of the electronic computer 100-1 performs packet transmission execution processing. I do.

First, the transmission unit 320 performs transmission command extraction processing (step S1).
Since the write pointer of the transmission command FIFO 211-J is updated, a difference occurs between the write pointer of the transmission command FIFO 211-J and the read pointer of the transmission command FIFO 211-J. Therefore, the command processing unit 322 transmits The transmission command 500 following the transmission command 500 at the position advanced by the number of read points of the transmission command FIFO 211-J from the head address of the command FIFO 211-J is transmitted from the transmission command FIFO 211-J on the main storage device 200 to the control device 120. The data is fetched via the memory control unit 310 and added to the read pointer of the transmission command FIFO 211-J in the command processing unit 322 by the number of transmission commands 500.

Next, the transmission unit 320 performs transfer length / transfer address setting processing (step S2).
The instruction processing unit 322 sets the transfer length described in the transfer length column 505 of the transmission command 500 in the transfer length register 231 -J on the main storage device 200 according to the extracted transmission command 500, and the main storage device The transmission buffer start address described in the transmission buffer start address column 504 of the transmission command 500 is set in the transfer address register 232 -J on the 200, and the ACK flag corresponding to the transmission command 500 is cleared. The ACK flag is represented by “1” indicating set or “0” indicating clear, and is set in the register 322 ′ of the instruction processing unit 322.

Next, the transmission unit 320 performs transmission data extraction processing (step S3).
The instruction processing unit 322 does not exceed the maximum data length of one packet on the switching network 400 from the transmission buffer start address set in the transfer address register 232-J on the main storage device 200, and the transfer length register 231-J. The memory control unit 310 is instructed to take out (read out) the data having the maximum data length not exceeding the transfer length set in (2) from the transmission buffer 221-J as transmission data and transfer it to the packet transmission unit 321. That is, the data length read from the main storage device 200 is Min (maximum data length of one packet, transfer length set in the transfer length register 231-J). However, Min (a, b) is a function that takes the value a when a < = b and the value b when a > b. For example, when the transfer length set in the transfer length register 231-J is 100 bytes, and the maximum data length of one packet is 256 bytes, the data length of the data retrieved from the main storage device 200 is Min (100, 256) bytes, That is, 100 bytes.

Next, the transmission unit 320 performs packet generation processing (step S4).
The packet transmission unit 321 writes necessary information in each column of the data transmission packet 600 in order to generate the data transmission packet 600. The packet transmission unit 321 writes the transmission type in the transmission type column 601, writes the destination computer number identifying the destination computer (electronic computer 100-2) in the destination computer number column 602, and sends the source computer (electronic computer 100-1). Is written in the sender computer number column 603. Further, the packet transmission unit 321 writes a connection number for identifying the destination process (the reception process of the destination computer) in the connection number column 604, and transmits a specific transmission command 500 (a transmission command 500 when the data transmission packet 600 is now generated). ) Is written in the transmission command number column 605. Further, the packet transmission unit 321 is generated with the same transmission command 500 (the above-mentioned specific transmission command 500) when the transmission data is divided into predetermined packet (data transmission packet 600) lengths. A packet number indicating which data transmission packet 600 of the transmission command 500 is the data transmission packet 600 is written in the packet number column 606. Further, the packet transmission unit 321 writes the data length indicating the length of the transmission data incorporated in the data transmission packet 600 in the data length column 607 and the transmission data read from the transmission buffer 221 -J in the data column 608. Write.

Next, the transmission unit 320 performs packet transmission processing (step S5).
The packet transmission unit 321 transmits the generated data transmission packet 600 to the switching network 400. As described above, the electronic computer 100-1 (source computer) transmits the data transmission packet 600 regardless of whether or not the reception command 510 is registered in the reception command FIFO 212-J of the electronic computer 100-2 (destination computer). Is transferred to the electronic computer 100-2.
For this reason, according to the communication system of the present invention, the electronic computer 100-1 (source computer) performs pre-control communication as described in the prior art on the electronic computer 100-2 (destination computer). Without this, the data transmission packet 600 can be transferred (data transfer can be performed).

Next, the transmission unit 320 performs a transfer length register / transfer address register update process (step S6).
The instruction processing unit 322 subtracts the data length when the data transmission packet 600 is transmitted (transferred) by the packet transmission unit 321 from the transfer length set in the transfer length register 231 -J. At the same time, the instruction processing unit 322 adds the data length when the data transmission packet 600 is transmitted (transferred) to the transmission buffer start address set in the transfer address register 232-J.

Next, the transmission unit 320 performs an interruption request confirmation process (step S7).
When a packet other than the data transmission packet 600 received by the packet reception unit 342 of the reception unit 340 is transferred to the instruction processing unit 322 via the context processing unit 341, the packet transmission unit 321 transmits the instruction processing unit 322. It is confirmed whether the receiving unit 340 (packet receiving unit 342) has received the interruption request packet 610 including the transmission command number that matches the transmission command number described in the transmission command number column 505 of the (transferred) data transmission packet 600. .
When the reception unit 340 (packet reception unit 342) has not received the interruption request packet 610 (step S7—NO), the transmission unit 320 performs reception packet reception (step S10).
When the reception unit 340 (packet reception unit 342) receives the interruption request packet 610 (step S7-YES), the instruction processing unit 322 responds to the interruption request packet 610 from the electronic computer 100-2 (destination computer). The transfer of the data transmission packet 600 is interrupted, and the transmission unit 320 performs a restart request reception waiting process (step S8).
Thus, according to the communication system of the present invention, useless data transfer that cannot be received by the electronic computer 100-2 (destination computer) can be prevented at an early stage, and useless data flowing through the exchange network 400 can be reduced.

The restart request reception waiting process (step S8) will be described.
The command processing unit 322 receives the restart request packet 630 including the transmission command number that matches the transmission command number described in the transmission command number column 505 of the data transmission packet 600 transmitted (transferred) by the packet transmission unit 321, Wait until the packet receiver 342) receives it.

  When the restart request packet 630 is received (step S8—YES), the transmission unit 320 performs transfer length / transfer address resetting processing (step S9). The transfer length / transfer address resetting process includes a first transfer length / transfer address resetting process and a second transfer length / transfer address resetting process. The first transfer length / transfer address resetting process is a process of transmitting (transferring) all transmission data when a restart request is made by the restart request packet 630. The second transfer length / transfer address resetting process is to transmit data (remaining data) other than the data already received by the destination computer (electronic computer 100-2) among the transmission data at the time of the restart request by the restart request packet 630. (Transfer) processing.

  In the first transfer length / transfer address resetting process, the instruction processing unit 322 stores the transfer command 500 previously extracted into the transfer length register 231 -J in the main storage device 200 and the transfer length column 505 of the transmission command 500. The described transfer length is set, and the transmission buffer start address described in the transmission buffer start address column 504 of the transmission command 500 is set in the transfer address register 232 -J on the main storage device 200.

  In the second transfer length / transfer address reset process, the instruction processing unit 322 executes the first transfer length / transfer address reset process, and then restarts the request packet from the transfer length set in the transfer length register 231-J. The received data length described in the received data length column 636 of 630 is subtracted. At the same time, the instruction processing unit 322 adds the received data length to the transmission buffer start address set in the transfer address register 232-J.

After performing the transfer length / transfer address resetting process (step S9), the transmission unit 320 performs the transmission data extraction process again (step S3).
According to the communication system of the present invention, the electronic computer 100-1 (source computer) only has to transfer again data that cannot be received by the electronic computer 100-2 (destination computer). The data transmission packet 600 can be transferred (data transfer can be performed) to the computer without performing the prior control communication as described in the prior art.
According to the communication system of the present invention, the electronic computer 100-1 (sender computer) refers to the received data length included in the restart request packet 630, and the data of the data previously transferred in the data transmission packet 600. Data having a data length other than the received data length (the remaining data) may be transferred to the electronic computer 100-2 (destination computer). Therefore, according to the communication system of the present invention, the transfer time when the remaining data is transferred from the electronic computer 100-1 (source computer) to the electronic computer 100-2 (destination computer) is, for example, transferred first. The transfer time when the transferred data is transferred from the electronic computer 100-1 (source computer) to the electronic computer 100-2 (destination computer) from the beginning is shorter.

The received packet reception process (step S10) will be described.
The command processing unit 322 receives the reception packet 620 including the transmission command number that matches the transmission command number described in the transmission command number column 505 of the data transmission packet 600 transmitted (transferred) by the packet transmission unit 321, with the reception unit 340 (packet It is confirmed whether the receiving unit 342) has received it.
When the reception unit 340 (packet reception unit 342) receives the reception packet 620 (step S10—YES), the transmission unit 320 performs ACK flag setting processing (step S11).
When the reception unit 340 (packet reception unit 342) has not received the reception packet 620 (step S10—NO), the transmission unit 320 performs a remaining transfer length confirmation process (step S12).

The ACK flag setting process (step S11) will be described.
The command processing unit 322 sets the ACK flag “1” corresponding to the transmission command 500 based on the reception packet 620 from the reception unit 340. The set ACK flag indicates that the reception packet 620 has been received from the destination computer (electronic computer 100-2) in response to the transmission command 500 (data transmission packet 600) from the transmission source computer (electronic computer 100-1). Indicates.

The remaining transfer length confirmation process (step S12) will be described.
The instruction processing unit 322 checks whether the transfer length set in the transfer length register 231 -J on the main storage device 200 is 0 or less.
If the transfer length set in the transfer length register 231-J is 0 or less, the transmission unit 320 performs ACK flag confirmation processing (step S13).
If the transfer length set in the transfer length register 231-J is larger than 0, the transmission unit 320 performs transmission data extraction processing again (step S3).

The ACK flag confirmation process (step S13) will be described.
The command processing unit 322 confirms whether the ACK flag corresponding to the transmission command 500 is set (is “1”).
When the ACK flag corresponding to the transmission command 500 is set, the transmission unit 320 completes the packet transmission execution process.
If the ACK flag corresponding to the transmission command 500 is clear, the transmission unit 320 performs the interruption request confirmation process again (step S7).

FIG. 14 is a flowchart showing packet reception execution processing (steps S21 to S33) which is the operation of the communication system of the present invention.
When the packet reception unit 342 of the reception unit 340 of the electronic computer 100-2 receives a packet transmitted from the electronic computer 100-1 (source computer) via the switching network 400, the electronic computer 100-2 (destination computer) The receiving unit 340 performs packet reception execution processing.

First, the receiving unit 340 performs packet discrimination processing (step S21).
The packet reception unit 342 of the reception unit 340 determines whether the received reception packet is the data transmission packet 600. When the received packet is the data transmission packet 600, the packet receiving unit 342 confirms the transmission type described in the transmission type column 601 of the received packet (data transmission packet 600).
If the received packet is not the data transmission packet 600, the reception unit 340 performs a transmission unit notification process (step S22).
When the received packet is the data transmission packet 600, the receiving unit 340 executes a context load process (step S23).

A transmission part notification process (step S22) is demonstrated.
Since the received packet is not the data transmission packet 600, the packet reception unit 342 transfers the packet to the command processing unit 322 of the transmission unit 320 via the context processing unit 341. The reception unit 340 completes the packet reception execution process after performing the transmission unit notification process.

The context load process (step S23) will be described.
In the case of a received packet (data transmission packet 600), the packet receiving unit 342 transfers the packet header of the received packet (referred to as the received packet 600) to the context processing unit 341. The context processing unit 341 extracts (loads) the context 700 corresponding to the connection number “J” described in the connection number column 604 of the packet header from the context tables 201-1 to 201-N of the main storage device 200. .

  Next, the reception unit 340 performs reception command confirmation processing (step S24).

  In case A2, that is, the received instruction processing flag in the received instruction processing flag column 701 of the loaded context 700 is “1”, and the transmission interrupted flag in the transmission interrupted flag column 705 is “0”. If the remaining reception buffer length is sufficient, the context processing unit 341 waits until a reception packet (data transmission packet 600) corresponding to the reception command 510 is received. When the received packet 600 is received (step S24—NO), the context processing unit 341 performs a first packet confirmation process (step S25).

  In case A1, that is, the transmission interrupted flag in the transmission interrupted flag column 705 of the loaded context 700 is “0”, and the connection number “J” described in the connection number column 604 in the packet header. When the reception command 510 is registered in the reception command FIFO 212-J corresponding to the above and the remaining reception buffer length is sufficient (step S24-NO), the context processing unit 341 performs the first packet confirmation processing (step S25).

  In case R2, that is, the received instruction processing flag in the received instruction processing flag column 701 of the loaded context 700 is “0”, and the transmission interrupted flag in the transmission interrupted flag column 705 of the context 700 is set. When it is “0” and the reception command 510 is not registered in the reception command FIFO 212-J corresponding to the value “J” described in the connection number column 604 in the packet header (step S24—YES), context processing The unit 341 performs remote instruction store processing (step S32).

  In the case of case R1, that is, the received instruction processing flag in the received instruction processing flag column 701 of the loaded context 700 is “0”, and the transmission interrupted flag in the transmission interrupted flag column 705 of the context 700 is set. The reception command 510 is registered in the reception command FIFO 212-J corresponding to the value “J” described in the connection number column 604 in the packet header, but the remaining reception buffer length is insufficient ( When the reception buffer is full (step S24-YES), the context processing unit 341 performs a remote instruction store process (step S32).

  In case R3, that is, the received instruction processing flag in the received instruction processing flag column 701 of the loaded context 700 is “1”, and the transmission interrupted flag in the transmission interrupted flag column 705 of the context 700 is set. When it is “0” and the remaining reception buffer length is insufficient (reception buffer full) (step S24—YES), the context processing unit 341 performs a remote instruction store process (step S32).

  In case D1, that is, the transmission interrupted flag in the transmission interrupted flag column 705 of the loaded context 700 is “1”, and the transmission interrupted flag in the transmission interrupted flag column 705 is “1”. If there is, the context processing unit 341 of the receiving unit 340 discards the received packet 600.

  The first packet confirmation process (step S25) will be described.

  In the case A2, since the received command processing flag in the received command processing flag column 701 of the loaded context 700 is “1”, it is generated with the same transmission command 500 (the specific transmission command 500 described above). It is not the first received packet (first packet) among the received packets 600 (step S25-NO). That is, the packet number described in the packet number field 606 in the packet header is not the first packet number, and the receiving unit 340 is waiting for the subsequent received packet 600. The receiving unit 340 Store processing (step S28) is performed.

  In the case A1, since the received command processing flag in the received command processing flag column 701 of the loaded context 700 is “0”, the same transmission command 500 (the specific transmission command 500 described above) is generated. This is the first received packet (first packet) of the received packets 600 (step S25—YES). That is, the packet number described in the packet number column 606 in the packet header represents the first packet number, and the reception unit 340 performs reception command extraction processing (step S26).

The received command extraction process (step S26) will be described.
The context processing unit 341 of the reception unit 340 refers to the reception command FIFO 212-J that matches the connection number “J” described in the connection number column 604 in the packet header, and is registered in the reception command FIFO 212-J. Receive command 510 is fetched. The context processing unit 341 includes a reception type column 511 of the reception command 510, a reception buffer start address column 514, a reception buffer length column 515, a reception type column 711 of the processing instruction command column 710 of the loaded context 700, a reception The contents described in the buffer start address column 712 and the reception buffer length column 713 are written (updated). The context processing unit 341 sets a reception command processing flag “1” in the reception command processing flag column 701 of the loaded context 700. The context processing unit 341 writes (updates) the transmission command number described in the transmission command number column 605 in the packet header in the transmission command number column 702 of the loaded context 700. The context processing unit 341 writes (updates) the packet number described in the packet number column 606 in the packet header in the last received packet number column 703 of the loaded context 700. The context processing unit 341 writes (sets) “0” in the received data length column 704 of the received processing instruction of the loaded context 700. In the step, since “0” is written in the transmission interrupted flag column 705 of the loaded context 700 (since the transmission interrupted flag is not set), no update is performed.

Next, the receiving unit 340 performs reception packet transmission processing (step S27).
When the context processing unit 341 of the reception unit 340 generates the reception packet 620 as a reply packet to the reception packet 600, the context processing unit 341 writes the reception type in the reception type column 621 and the destination described in the destination computer number column 602 in the packet header. The computer number is written in the destination computer number column 621, the source computer number described in the source computer number column 603 in the packet header is written in the source computer number column 623, and the connection number column 604 in the packet header is written. The described connection number is written in the connection number column 624, and the transmission command number described in the transmission command number column 605 in the packet header is written in the transmission command number column 625. The context processing unit 341 transmits the acceptance packet 620 to the transmission source computer (electronic computer 100-1) via the transmission unit 320. Thereafter, the reception unit 340 performs reception data store processing (step S28).

The received data store process (step S28) will be described.
The context processing unit 341 transmits a reception command write instruction to the packet reception unit 342. The packet reception unit 342 stores (writes / registers) the data (reception data) described in the data column 608 of the reception packet 600 in the reception buffer 222-J according to the reception command write instruction.
The buffer length described in the buffer length column 713 of the processing instruction received in the context 700 is BLEN, the data length described in the received data length column 704 of the processing instruction received in the context 700 is RLEN, and the received packet 600 When the data length described in the data length column 607 is PLEN, the data size WLEN to be written to the reception buffer 222-J on the main storage device 200 is determined by Equation 1.

  The length of the packet receiving unit 342 that WLEN designates the data (received data) described in the data column 608 of the received packet 600 as the address obtained by adding RLEN to the reception buffer start address 712 of the receiving command being processed in the context 700. Just write.

Next, the receiving unit 340 performs final packet confirmation processing (step S29).
The context processing unit 341 of the receiving unit 340 checks whether the data length described in the data length column 607 of the received packet 600 is zero.
When the data length is 0 (step S29-YES), the received packet (data transmission packet 600) is the same as the received packet 600 generated by the same transmission command 500 (the specific transmission command 500 described above). Since it is the last received packet (final packet), the receiving unit 340 performs a reception command completion process (step S30).
When the data length is not 0 (step S29-NO), the received packet (data transmission packet 600) is the received packet 600 generated by the same transmission command 500 (the specific transmission command 500 described above). Since it is not the last received packet (final packet), the receiving unit 340 performs context write-back (step S31).

The reception command completion process (step S30) will be described.
The context processing unit 341 clears the received instruction processing flag in the received instruction processing flag field 701 of the loaded context 700. That is, “0” is written (set) in the received command processing flag field 701.

The context write-back (step S31) will be described.
The context processing unit 341 writes back the loaded context 700 in the context table 201-J of the main storage device 200, and the reception unit 340 completes the packet reception execution process.

  According to the communication system of the present invention, since the electronic computer 100-1 (source computer) performs data transfer without performing prior control communication, the latency (execution time) from the start to the completion of data transfer is the conventional one. This is less than the latency (execution time) from the start of pre-control communication as described in the technology to the completion of data transfer.

The remote instruction store process (step S32) will be described.
In the cases R1, R2, and R3, when generating the remote command 640, the context processing unit 341 writes the remote command type in the remote command type column 641, and the destination described in the destination computer number column 602 in the packet header. The computer number is written in the destination computer number column 642, the source computer number described in the source computer number column 603 in the packet header is written in the source computer number column 643, and the connection number column 604 in the packet header is written. The described connection number is written in the connection number column 644, and the transmission command number described in the transmission command number column 605 in the packet header is written in the transmission command number column 645.
When the reception instruction 510 is registered in the reception instruction FIFO 212-J, but the full reception buffer 222-J is detected, the context processing unit 341 sets the data length described in the data length column 607 in the packet header. Write in the received data length column 646 as the received data length.

Next, the receiving unit 340 performs an interruption request packet transmission process (step S33).
In the cases R1, R2, and R3, when generating the interruption request packet 610 as a reply packet to the received packet 600, the context processing unit 341 writes the interruption request type in the interruption request type column 611, and the destination computer in the packet header. The destination computer number described in the number column 602 is written in the destination computer number column 612, the source computer number described in the source computer number column 603 in the packet header is written in the source computer number column 613, and the packet number The connection number described in the connection number column 604 in the header is written in the connection number column 614, and the transmission command number described in the transmission command number column 605 in the packet header is written in the transmission command number column 615.

  In the case R1, the context processing unit 341 transmits the interruption request packet 610 to the transmission source computer (electronic computer 100-1) via the transmission unit 320, and at the same time extracts the first reception instruction 510 from the reception FIFO 212. , Registered in the in-process received command column 710 of the context 700, set the received command processing flag “1” in the received command processing flag column 701, and set the transmission command number column 702 in the transmission command number column 605 in the packet header. Write the described transmission command number, write “0” indicating that no packet has been received in the last received packet number column 703, write “0” in the received data length column 704 of the receiving command being processed, and stop transmission The transmission interrupted flag “1” is set in the completed flag column 705, and the packet reception execution process is completed.

  In the case R2, the context processing unit 341 sets the reception command processing flag “1” in the reception command processing flag column 701 at the same time as transmitting the interruption request packet 610 to the transmission source computer (electronic computer 100-1). The transmission command number described in the transmission command number column 605 in the packet header is written in the transmission command number column 702, and “0” indicating that the packet has not been received is written in the last received packet number column 703. Write “0” in the received data length column 704 of the middle reception command, set the transmission interrupted flag “1” in the transmission interrupted flag column 705, and complete the packet reception execution processing.

  In the case R3, the context processing unit 341 transmits the interruption request packet 610 to the transmission source computer (the electronic computer 100-1), and at the same time, receives the reception command processing flag column 701, the transmission command number column 702, and the last received packet number. Without updating the column 703, the transmission suspended flag “1” is set in the transmission suspended flag column 705, and the packet reception execution process is completed.

  According to the communication system of the present invention, since the electronic computer 100-2 (destination computer) transmits the interruption request packet 610 for interrupting the transfer of the data transmission packet 600, the electronic computer 100-2 (destination computer) Unnecessary data transfer that cannot be received can be prevented at an early stage, and wasteful data flowing through the switching network 400 can be reduced.

  FIG. 15 is a flowchart showing reception command execution processing (steps S41 to S45) which is the operation of the communication system of the present invention. The reception process 111-J on the arithmetic unit 110 writes (registers) the reception instruction 510 in the main storage device 200 (reception instruction FIFO 212-J), and the reception instruction in the context processing unit 341 (held by the register 341 ′) When the number of the transmission commands 500 is added to the write pointer of the FIFO 212-J, the reception command execution processing is performed by the reception unit 340 (context processing unit 341).

First, the context processing unit 341 performs context loading processing (step S41).
The context processing unit 341 retrieves (loads) the context 700-J with reference to the context tables 201-1 to 201-N by the reception instruction 510 registered in the reception instruction FIFO 212-J.

Next, the context processing unit 341 performs an interruption instruction confirmation process (step S42).
The context processing unit 341 confirms whether the transmission interrupted flag “1” is set in the transmission interrupted flag column 705 of the loaded context 700.
When the transmission interrupted flag “1” is set, the context processing unit 341 performs a remote command extraction process (step S43).
When the transmission interrupted flag is not set (it is “0”), the context processing unit 341 performs a restart request process (step S45).

The remote command fetch process (step S43) will be described.
As the write pointer of the remote instruction FIFO 213-J is updated, a difference occurs between the write pointer of the remote instruction FIFO 213-J and the read pointer of the remote instruction FIFO 213-J. The remote command 640 next to the remote command 640 at the position advanced by the number of read points of the remote command FIFO 213-J from the head address of the command FIFO 213-J is transferred from the remote command FIFO 213-J on the main storage device 200 to the control device 120. The number is fetched via the memory control unit 310, and is added to the read pointer of the remote command FIFO 213-J in the context processing unit 341 by the number of remote commands 640.

Next, the context processing unit 341 performs context writing processing (step S44).
The context processing unit 341 clears the transmission interrupted flag in the transmission interrupted flag column 705 of the loaded context 700. That is, “0” is written (set) in the transmission interrupted flag column 705. The context processing unit 341 writes back the loaded context 700 in the context table 201-J of the main storage device 200.

The restart request process (step S45) will be described.
When the context processing unit 341 generates the restart request packet 630 by the extracted remote command 640, the context processing unit 341 writes the restart request type in the restart request type column 631, and the destination computer number described in the destination computer number column 642 of the remote command 640 Is written in the destination computer number 632, the source computer number described in the source computer number column 643 of the remote command 640 is written in the source computer number column 633, and the connection number described in the connection number column 644 of the remote command 640 Is written in the connection number column 634, and the transmission command number described in the transmission command number column 645 of the remote command 640 is written in the transmission command number column 635.
When the context processing unit 341 resumes the transmission when the transmission (transfer) is interrupted due to the reception buffer 222-J being full, the context processing unit 341 has received the data described in the received data length column 646 of the remote command 640. The data length is written in the received data length column 636.
The context processing unit 341 transmits the restart request packet 630 to the switching network 400 via the transmission unit 320.
After performing the restart request process, the context processing unit 341 completes the reception instruction execution process.

  As described above, according to the communication system of the present invention, the electronic computer 100-2 (destination computer) transmits the resume request packet 630 for resuming the transfer of the interrupted data transmission packet 600. -1 (source computer) may transfer only data that cannot be received by the electronic computer 100-2 (destination computer). Therefore, according to the communication system of the present invention, the data transmission packet 600 is transferred to the electronic computer 100-2 (destination computer) without performing the pre-control communication as described in the prior art. (Data transfer can be performed).

  The restart request packet 630 includes the data length (received data length) of the data written in the reception buffer 222-J among the data of the data transmission packet 600 from the electronic computer 100-1 (source computer). In this case, the restart request packet 630 is information (packet) for requesting transfer of data other than the data written in the reception buffer 222 among the data of the data transmission packet 600 from the electronic computer 100-1 (source computer). ). As described above, according to the communication system of the present invention, the electronic computer 100-1 (sender computer) refers to the received data length included in the restart request packet 630 and transfers it first in the data transmission packet 600. Data having a data length other than the received data length (the remaining data) among the data lengths of the received data may be transferred to the electronic computer 100-2 (destination computer). Therefore, according to the communication system of the present invention, the transfer time when the remaining data is transferred from the electronic computer 100-1 (source computer) to the electronic computer 100-2 (destination computer) is, for example, transferred first. The transfer time when the transferred data is transferred from the electronic computer 100-1 (source computer) to the electronic computer 100-2 (destination computer) from the beginning is shorter.

  As described above, according to the communication system of the present invention, the electronic computer 100-1 (source computer) controls the electronic computer 100-2 (destination computer) in advance as described in the prior art. The data transmission packet 600 can be transferred without performing communication (data transfer can be performed).

  According to the communication system of the present invention, since the electronic computer 100-1 (source computer) performs data transfer without performing prior control communication, the latency (execution time) from the start to the completion of data transfer is the conventional one. This is less than the latency (execution time) from the start of pre-control communication as described in the technology to the completion of data transfer.

  According to the communication system of the present invention, since the electronic computer 100-2 (destination computer) transmits the interruption request packet 610 for interrupting the transfer of the data transmission packet 600, the electronic computer 100-2 (destination computer) Unnecessary data transfer that cannot be received can be prevented at an early stage, and wasteful data flowing through the switching network 400 can be reduced.

  As described above, according to the communication system of the present invention, the electronic computer 100-2 (destination computer) transmits the resume request packet 630 for resuming the transfer of the interrupted data transmission packet 600. -1 (source computer) may transfer only data that cannot be received by the electronic computer 100-2 (destination computer). Therefore, according to the communication system of the present invention, the data transmission packet 600 is transferred to the electronic computer 100-2 (destination computer) without performing the pre-control communication as described in the prior art. (Data transfer can be performed).

  The restart request packet 630 includes the data length (received data length) of the data written in the reception buffer 222-J among the data of the data transmission packet 600 from the electronic computer 100-1 (source computer). In this case, the restart request packet 630 is information (packet) for requesting transfer of data other than the data written in the reception buffer 222 among the data of the data transmission packet 600 from the electronic computer 100-1 (source computer). ). As described above, according to the communication system of the present invention, the electronic computer 100-1 (sender computer) refers to the received data length included in the restart request packet 630 and transfers it first in the data transmission packet 600. Data having a data length other than the received data length (the remaining data) among the data lengths of the received data may be transferred to the electronic computer 100-2 (destination computer). Therefore, according to the communication system of the present invention, the transfer time when the remaining data is transferred from the electronic computer 100-1 (source computer) to the electronic computer 100-2 (destination computer) is, for example, transferred first. The transfer time when the transferred data is transferred from the electronic computer 100-1 (source computer) to the electronic computer 100-2 (destination computer) from the beginning is shorter.

FIG. 1 is a block diagram showing a configuration of a communication system according to the present invention. FIG. 2 is a block diagram showing the configuration of the communication device of the electronic computer in the communication system of the present invention. FIG. 3 is a block diagram showing the configuration of the arithmetic unit of the electronic computer in the communication system of the present invention. FIG. 4 is a block diagram showing the configuration of the main storage device of the electronic computer in the communication system of the present invention. FIG. 5 shows a transmission command in the communication system of the present invention. FIG. 6 shows a data transmission packet in the communication system of the present invention. FIG. 7 shows a reception command in the communication system of the present invention. FIG. 8 shows the context in the communication system of the present invention. FIGS. 9A and 9B show an interruption request packet in the communication system of the present invention. FIG. 10 shows an acceptance packet in the communication system of the present invention. FIGS. 11A and 11B show remote commands in the communication system of the present invention. FIGS. 12A and 12B show a restart request packet in the communication system of the present invention. FIG. 13 is a flowchart showing packet transmission execution processing which is the operation of the communication system of the present invention. FIG. 14 is a flowchart showing packet reception execution processing which is the operation of the communication system of the present invention. FIG. 15 is a flowchart showing a reception command execution process which is an operation of the communication system of the present invention. FIG. 16 is a diagram for explaining processing after the context processing unit captures a context in the communication system of the present invention.

Explanation of symbols

100-1 electronic computer 100-2 electronic computer 100-3 electronic computer 110 arithmetic device 111, 111-1 to 111-N process 113 driver software 120 control device 200 main storage device 201 context table 211, 211-1 to 211-N Send command FIFO
212, 212-1 to 212-N Receive command FIFO
213, 213-1 to 213-N Remote command FIFO
221, 221-1 to 221 -N transmission buffer 222, 222-1 to 222 -N reception buffer 231 transfer length register 232 transfer address register 300 communication device 310 memory control unit 320 transmission unit 321 packet transmission unit 322 instruction processing unit 322 ′ Register 340 Reception unit 341 Context processing unit 341 'Register 342 Packet reception unit 400 Switching network 500 Transmission command 501 Transmission type column 502 Destination computer number column 503 Connection number column 504 Transmission buffer start address column 505 Transfer length column 510 Reception command 511 Reception type Field 512 Destination computer number field 513 Connection number field 514 Reception buffer start address field 515 Reception buffer length field 600 Data transmission packet 601 Transmission type field 602 Destination computer number field 603 Source computer number field 604 Connection Number field 605 Transmission command number field 606 Packet number field 607 Data length field 608 Data field 610 Interrupt request packet 611 Interrupt request type field 612 Destination computer number field 613 Source computer number field 614 Connection number field 615 Transmission command number field 616 Received data Long field 620 Accepted packet 621 Accepted type field 622 Destination computer number field 623 Source computer number field 624 Connection number field 625 Transmission command number field 630 Resume request packet 631 Resume request type field 632 Destination computer number field 633 Source computer number field 634 Connection number column 635 Transmission command number column 636 Received data length column 640 Remote command 641 Remote command type column 642 Destination computer number column 643 Source computer number column 644 Connection number column 645 Transmission command number column 646 Received data length column 700 701 Receive command processing flag column 702 Transmission command number column 703 Last received packet number column 704 Received data length column 705 of processing received command Transmission interrupted flag column 710 Received command column 711 Processing type of received command Field 712 Receive buffer start address field for receive command being processed 713 Buffer length field for receive command being processed

Claims (3)

A first computer connected to the network;
A second electronic computer connected to the network and transferring packets containing data to the first electronic computer;
The first electronic computer includes a communication device, an arithmetic device, a reception buffer, and a holding buffer.
The communication device
A first reception processing unit that writes the data of the packet into the reception buffer when a reception command is issued by the arithmetic unit;
When the reception instruction is not issued by the arithmetic unit, a suspension request for interrupting the transfer of the packet is transmitted to the second electronic computer, and transfer information regarding the packet is registered in the holding buffer. Two reception processing units;
When the next reception command is issued by the arithmetic device, the second electronic computer issues a restart request for restarting the transfer of the interrupted packet with reference to the transfer information registered in the holding buffer. A transmission processing unit to transmit to ,
When the data length of the data written to the reception buffer by the first reception processing unit exceeds the data length of data that can be held by the reception buffer, the interruption request is transmitted to the second electronic computer. And a third reception processing unit for registering the transfer information in the holding buffer,
The transfer information and the restart request include a data length of the data written in the reception buffer by the first reception processing unit of the data,
The resumption request is a communication system which is information for requesting transfer of data other than data written in the reception buffer among the data . An electronic computer connected via a network to another electronic computer that transfers packets containing data,
A communication device;
A reception command holding unit;
An arithmetic unit that issues a reception command and registers it in the reception command holding unit;
A receive buffer;
A holding buffer,
The communication device
A first reception processing unit that writes the data of the packet to the reception buffer when the reception command is registered in the reception command holding unit;
When the reception command is not registered in the reception command holding unit, a suspension request for interrupting the transfer of the packet is transmitted to the other electronic computer, and transfer information regarding the packet is registered in the holding buffer. A second reception processing unit,
When the next received command issued by the arithmetic unit is registered in the received command holding unit, the transfer of the interrupted packet is resumed with reference to the transfer information registered in the holding buffer. A transmission processing unit for transmitting a restart request for the other electronic computer ;
When the data length of the data written to the reception buffer by the first reception processing unit exceeds the data length of data that can be held by the reception buffer, the interruption request is transmitted to the second electronic computer. And a third reception processing unit for registering the transfer information in the holding buffer,
The transfer information and the restart request include a data length of the data written in the reception buffer by the first reception processing unit of the data,
The resuming request is an electronic computer that is information for requesting transfer of data other than data written in the reception buffer . A communication method using an electronic computer connected to another electronic computer for transferring a packet containing data via a network and having an arithmetic device, a reception buffer, and a holding buffer,
Writing the data of the packet into the reception buffer when a reception command is issued by the arithmetic unit;
A step of transmitting an interruption request for interrupting the transfer of the packet to the other electronic computer when the reception command is not issued by the arithmetic unit and registering transfer information relating to the packet in the holding buffer When,
When the next reception command is issued by the arithmetic unit, the transfer information registered in the holding buffer is referred to and a restart request for restarting the transfer of the interrupted packet is issued to the other electronic computer. and the step of transmitting to,
When the data length of the data written to the reception buffer by the writing step exceeds the data length of the data that can be held by the reception buffer, the interruption request is transmitted to the second electronic computer, and Registering transfer information in the holding buffer,
The transfer information and the restart request include a data length of the data written in the reception buffer by the writing step of the data,
The communication method , wherein the restart request is information for requesting transfer of data other than the data written in the reception buffer .

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