JPH10105420A - Remote procedure call processing method - Google Patents

Abstract

(57) [Summary] (with correction) [PROBLEMS] To reduce the processing load on the other procedure execution side in response to a multiple execution request, and control the cache content retention period and the size of the cache memory. A distributed system is configured by arranging a plurality of processing devices (2, 3, 4, 5) in a hierarchical structure of three or more layers and multiplexing processing devices (3, 4) on the procedure execution side. The processing means 5 having received the remote procedure call request message detects a multiplex request message based on the contents of the user data portion included in the remote procedure call request message, selects one of the messages, and performs its own processing. Is executed, and the execution result is returned to the transmission source processing device 3 of the selected multiplex request message, and information obtained by duplicating the execution result is returned to the transmission source processing device 4 of the unselected multiplex request message. The cache information for the multiplexed remote procedure call request is managed based on the information on the number of processing means of the destination requested for the remote procedure call.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a remote procedure call processing system in which a distributed system provides various services in the form of procedures, and more particularly, to a multiplexed procedure execution side in a three-layer distributed system. The present invention relates to a remote procedure call processing method that is suitable for the case.

[0002]

2. Description of the Related Art Conventionally, a three-tiered client / server model has been known as a model for constructing a distributed system. In the three-tier client / server model, component software (client, server) that configures a distributed system is functionally classified into three layers: a presentation layer (client), a function layer (server), and a data layer (nest server). I do. Then, component software is developed based on this classification. Further, when the configuration of the system needs to be changed, it is possible to replace only a certain component and to minimize the influence on other portions.
As a communication means between the presentation layer (client), function layer (server), and data layer (nest server), a remote procedure call processing method (hereinafter, referred to as "RPC") is generally used.

In RPC, a procedure executing side normally executes a procedure each time a request is made from a procedure requesting side, and returns a processing result to the procedure requesting side. Therefore, the procedure execution side executes the procedure M times if the request from the procedure request side comes M times, even if the request contents are exactly the same. In a configuration such as a three-layer client / server model, when multiplexing the procedure execution side (server) of the function layer, the multiplexed procedure execution side of the function layer is further multiplexed by another procedure execution side (for example, data). When a procedure execution request is issued to a nested server of a layer, another procedure executing side that receives the procedure execution request may need to perform the same procedure procedure a plurality of times. Side processing load increases.

As a general method for reducing the processing load for a plurality of processing requests having the same contents, first, for example,
A cache method is known. In the cache method, when a procedure execution side stores (caches) the contents of a recent execution request and its execution result in a computer in which the procedure execution side is present, and receives a procedure execution request from the procedure execution requesting side, the procedure execution side executes the procedure. The contents of the execution request are compared with the contents of the cache. If there is an execution request having the same contents, the execution result (cache contents) is accepted as if the procedure was actually executed as the execution result of the procedure execution request. Is returned to the procedure request side.

[0005] As a second method, for example, as described in Japanese Patent Application Laid-Open No. 63-30956 previously proposed by the present applicant, the method is not applied to RPC, but depends on a message inputted. The processing execution side that executes the processing,
There is known a method in which an input multiplex message is detected, one of them is selected, and a process of one's own is executed. Here, by adding an identifier called an event number to the message, the receiving side can detect the multiplexed message, collect the multiplexed message by the receiving side, and use only one message selected from the collected messages. Is executed only once, thereby preventing the same process from being performed a plurality of times.

[0006]

However, in the remote procedure call processing method in which the procedure execution side of the three-tiered client / server model is multiplexed, even if the above-described caching method is used, the cache content storage period However, it is difficult to control when and in what order the cache contents should be discarded. Further, there is a problem that it is difficult to estimate a memory capacity required for the cache, and it is difficult to dynamically secure a memory that can operate the cache suitably.

In the method disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 63-30956, since it is not assumed that the processing result on the receiving side is received as a response as in RPC, the processing for processing a multiplex request message is performed. Even if the execution side selects and executes one of the multiple request messages and returns the execution result to each request source as a multiple response message, the content of the multiple request message (for example,
If the input arguments of the RPC are different, the execution results are also different, so that there is a problem that the request source that transmitted the RPC request may have inconsistency between the contents of the request message and the contents of the response message. Further, in this method, when the multiplexed message receiving side determines the multiplexed message, the event identifier used for identifying the multiplexed message and the content of the multiplexed message are obtained after the number of multiplexed messages that should have actually arrived is received. However, there is also a problem that it is necessary to store the data for a predetermined period of time, and it is necessary to secure a large storage area therefor.

An object of the present invention is to provide a three-tier client /
When the procedure execution side of the server model is multiplexed, the processing load can be efficiently reduced by the other procedure execution side in response to the multiple execution request issued by this procedure execution side, and the cache content storage period and cache memory It is an object of the present invention to provide a remote procedure call processing method capable of effectively controlling the size of the remote procedure call.

[0009]

In order to achieve the above object, the present invention has a plurality of processing means having a hierarchical structure of three or more layers, multiplexing processing means on the procedure execution side, and transmitting these processing means. In the remote procedure call processing method in a distributed system connected by a network, the processing unit that has received the remote procedure call request message generates a multiplex request message based on the content of the user data section included in the remote procedure call request message. Detecting, selecting one of them, executing its own process using the selected multiplex request message, returning the execution result to the source processing means of the selected multiplex request message, and returning the execution result. Return the duplicated information to the source processing means of the unselected multiplex request message In both, the cache information for the multiplexed remote procedure call request is managed based on information on the number of processing means of the destination requested for the remote procedure call included in the remote procedure call request message. According to such a method, the processing load can be efficiently reduced by the other procedure execution side in response to the multiple execution request issued by the procedure execution side, and the storage period of the cache contents and the size of the cache memory can be effectively reduced. It can be controlled.

In the above-mentioned remote procedure call processing method, preferably, the processing means for requesting the remote procedure call includes information on the self-processing means and the event identifier indicating the order of generation of the request, and the lower order destination for requesting the remote procedure call. A first remote procedure call request message to which information of the number of processing means is added is sent to the transmission network. The destination processing means is a multiplexed processing means, and the received first remote procedure call message is received. A remote procedure call request message of a remote procedure call request for a lower processing means generated during its own processing started based on the request message includes the event identifier of the first remote procedure call request message and the destination processing device. Add a number and , The second remote procedure call request message transmitted to the transmission network, the second
Receiving the remote procedure call request message of the above, further manages the cache information for the multiplexed remote procedure call request based on the number of destination processing devices in the remote procedure call request message. With this method, a multicast configuration can be obtained.

In the above remote procedure call processing method, preferably, the processing means requesting a remote procedure call belongs to the same processing when calling a plurality of processing means belonging to the same processing in response to one remote procedure call request. One of the plurality of processing means is arbitrarily selected by the requesting source, and information of an event identifier indicating the order of generation of the request and information of a lower-level destination processing means requesting a remote procedure call are called. A first remote procedure call request message to which the number information has been added is sent to the transmission network, and the called processing means (proxy processing means) executes its own processing, and executes the contents requested by the request source. The first remote control is received by copying and calling the remaining processing means. Each of the processing means, which has duplicated the lossy call request message and transmitted it to the transmission network and received the first remote procedure call request message, executes its own processing started based on the received first remote procedure call request message. The event identifier of the first remote procedure call request message and the number of destination processing units are added to the remote procedure call request message of the remote procedure call request for the lower-level processing means generated during the second procedure. Sending the remote procedure call request message to the transmission network, and receiving the second remote procedure call request message, the lower-level processing means processes the destination in the remote procedure call request message. Based on the registered number, which was to manage the cache information for multiplexed remote procedure call request, by such method, and those which may indirect multicast configuration.

In the above remote procedure call processing method, preferably, the processing means having received the first remote procedure call request message has occurred during its own processing started based on the first remote procedure call request message. The second remote procedure call request message of the remote procedure call request is further added with a nested event serial number indicating the order in which the requests occurred during its own processing are transmitted to the transmission network.

In the above-mentioned remote procedure call processing method, it is preferable to perform a process of detecting a multiplex request message belonging to the same process having the same event identifier or a process having the same nest event serial number having the same event identifier. The period during which the detection processing of the multiplex request message to which the multiplex request message belongs is performed until the fetch of the multiplex request messages of the number equal to the number of the destination processing devices is completed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A remote procedure call processing system according to an embodiment of the present invention will be described below with reference to FIGS. [Overall Configuration of Distributed System] First, a distributed system using a remote procedure call processing method according to an embodiment of the present invention will be described with reference to FIG. FIG.
It is a block diagram showing the whole distributed system using a remote procedure call processing system by one embodiment of the present invention.

The distributed system shown in FIG. 1 shows a three-tier client / server model in which procedure execution sides (servers) are multiplexed. In addition, the present invention
Although the present invention can be applied to a client / server model having a three-layer structure or more, a three-layer structure will be described here.

Each of the processing devices 2, 3, 4, and 5 is connected to the communication medium 1 and communicates with another processing device via the communication medium 1. As the communication medium 1, L
Any communication line such as AN, WAN, wireless LAN, etc. can be used. As the processing devices 2, 3, 4, and 5, computers such as workstations, personal computers, controllers, mainframe computers, and portable computers can be used. Processing units 2, 3,
Reference numerals 4 and 5 may be different types of computers.

The processing device 2 includes a client 22 and an RPC
It has a processing unit 20. The client 22 is, for example, a user program or an application program created or used by a user, and requests a procedure of another processing device as necessary to refer to information necessary for processing. Here, as a procedure of another processing apparatus, for example, a server 3 described later is used.
3, 43 and the nest server 53 correspond.

The RPC processing unit 20 transmits a procedure execution request to other processing units 3, 4, and 5 as an RPC request message based on a remote procedure call (RPC) request requested from the client 22.
Further, the RPC processing unit 20 receives the RPC response message holding the execution result from the other processing devices 3, 4 and 5, and returns it to the requesting client 22.

Although not shown, the RPC processing unit 20 may include a server in the processing device 2, and in that case, the RPC processing unit 20 itself exists based on an RPC request message requested from another processing device. Run the server in the processing unit,
The execution result is returned to the requesting processing device.

The processing device 3 has a server 33 and an RPC processing unit 30. The processing device 4 includes the server 43 and the RPC
It has a processing unit 40. It is assumed that the servers 33 and 43 are multiplexed procedures.

The servers 33 and 43 are, for example, user programs and application programs created or used by the user. The servers 33 and 43 execute their own processing in response to a request from the client 22 of another processing apparatus 2 and execute the processing. The result is returned to the calling client 22 via the RPC processing units 30 and 40. If necessary, the client 2 refers to information necessary for processing.
Similarly to 2, the request is made to the procedure of the other processing device 5.

The RPC processing units 30 and 40 have the same function as the RPC processing unit 20.

It should be noted that the servers 33 and 43 do not necessarily have to be completely duplicated to perform exactly the same processing, but may be procedures having different processing. For example, in the N-version programming method, a plurality of programs of different versions are prepared, their executions are performed in parallel, the execution results are compared, and a new program is tested.
May be different versions of a procedure that performs the same processing but slightly differs in processing details.

The processing device 5 includes a nest server 53 and an RPC
It has a processing unit 50. The nest server 53 is, for example, a user program or an application program created or used by a user, similarly to the servers 33 and 43, and performs its own processing in response to a request from a server of another processing device 3 or 4. It executes and returns the execution result to the calling server. Further, as required, the client 22 may request a procedure of another processing device to refer to information necessary for processing as in the case of the client 22.

The RPC processor 50 has the same function as the RPC processor 20.

The nest server 53 may be simply referred to as a “server”. In the present embodiment, the nest server 53 performs processing according to the request messages transmitted by the servers 33 and 43 as an example. In order to facilitate the distinction, it will be referred to as a “nest server”.

The servers 33 and 43 and the nest server 53
Is identified by a “procedure identifier” that indicates what kind of processing it can perform. As the procedure identifier, for example, an identifier for uniquely identifying the procedure name or the processing content of the procedure can be used. The procedure identifier is 1
One procedure identifier may correspond to one server, or a plurality of procedure identifiers may correspond to one server. A plurality of servers may use the same procedure identifier.

In this embodiment, the server 3
3, 43 have the same procedure identifier.

In the description of FIG. 1, the processing units 2, 3,
4 and 5 are a client 22, a server 33,
It has a server 43 and a nest server 53, but may have other clients, servers and nest servers. For convenience of description of the present embodiment, FIG.
It is illustrated as follows.

In FIG. 1, the client 22, the servers 33 and 43, and the nest server 53 are present in different processing units 2, 3, 4, and 5, respectively. They may coexist in a processing device, or all may exist in one processing device.

Here, the overall flow at the time of an RPC execution request in the remote procedure call processing method according to the present embodiment will be described with reference to the arrows shown in FIG.
The server 33, 43 is executed by the RPC request generated from the client 22, and the nest server 53 is executed by the RPC request generated during execution of each server 33, 43. Is shown.

When an RPC request is issued from the client 22 of the processing device 2 to the server (arrow 61), the RP
The C processing unit 20 acquires an address in a processing device of a server that can execute the processing. Here, the servers 33 and 4
3 is executable, the RPC processing unit 20 transmits an RPC request message to the RPC processing units 30 and 40 of the processing devices 3 and 4 having the respective servers 33 and 43 (arrows 62a and 62b). .

Here, the RPC request message includes information such as an event identifier for identifying an event in which an RPC request has occurred from the client and the number of issued RPCs, and is transmitted in accordance with an RPC request message format described later with reference to FIG. You.

After receiving the RPC request message, the RPC processing units 30, 40 of the processing devices 3, 4 execute the server after storing the event identifier and the number of issued RPCs attached to the messages (arrows 63a, 64b). ).

When each of the servers 33 and 43 issues an RPC request to another server (nest server 53) (arrows 64a and 64b), the RPC processing units 30 and 40
The stored event identifier and the number of issued RPCs are
In addition to the C request multiplex message, the RPC request multiplex message is transmitted to the processing device 5 of the nest server (arrow 6).
5a, 65b).

In the processing device 5 having received the RPC request multiplex message, the RPC processing unit 50
From the PC request multiplex messages, the RPC request multiplex message generated by the same event from the client 22 is determined based on the event identifier and the number of issued RPCs, and the first one is selected from among them, and the nest server 5
Execute 3 (arrow 66).

Next, an overall flow of an RPC response in the remote procedure call processing method according to the present embodiment will be described with reference to FIG. FIG. 2 is a block diagram showing the overall configuration of a distributed system using the remote procedure call processing method according to one embodiment of the present invention.

The execution result of the nest server 53 and the input argument therefor become cache information of the nest server 53 and are stored in the RPC processing unit 50 (arrow 67). For the remaining RPC request multiplex messages other than the first one, the nest server 53 is not executed and no RPC processing is performed.
If there is an equal input argument in the execution result cache information, the execution result information is directly returned to the caller as the execution result. If there is no equal input argument, the nest server 53 is executed using the input argument. The execution result also becomes cache information. However, when the RPC request multiplex messages (having the same event identifier) are received by the number of RPCs issued on the client side, the cache information is cleared.

The RPC response message is passed to the RPC processing units 30 and 40 of the calling servers 33 and 43 (arrows 68a and 68b), and the execution result is passed to the servers 33 and 43 that are executing (arrows 69a and 69b). ).

Since the execution results of the servers 33 and 43 are returned to the calling client 22, the RPC processing unit 3
It is returned to 0, 40 (arrows 70a, 70b). The RPC processing units 30 and 40 create an RPC response message and return it to the processing device 2 of the calling client 22 (arrows 71a and 71b).

The RPC processing unit 20 sends the RP
The RPC response messages corresponding to the number of issued Cs are received, one of them is selected by a predetermined selecting means, and the selected one is returned to the client 22 as an execution result of the server.
The information in the cache may be cleared after a certain period of time.

[Format of RPC Request Message]
Next, a format of an RPC request message transmitted between the processing devices 2, 3, 4, and 5 via the communication medium 1 will be described with reference to FIG. FIG. 3 is an explanatory diagram of the format of an RPC request message transmitted in the remote procedure call processing method according to one embodiment of the present invention.

RPC request message format 160
Is the RPC control header 161 and the event identifier 16
3, an issue number part 164, a serial number part 165, and a user data part 166.

The RPC control header 161 is an area for storing information used for controlling transmission and reception of an RPC request message. The RPC request header section 161 has an execution request procedure identifier section 162 which is an area for storing a procedure identifier of a server to which execution is requested by an RPC request.
It is included.

The RPC request header section 161 includes R
A destination address, a source address, a request / response message identification flag, a control code for error detection, and the like necessary for controlling transmission and reception of the PC request message are included.
Since it has no direct relation to the present invention, illustration and description are omitted.

The event identifier section 163 is an area for storing an event identifier used in the present embodiment.
The issuance number section 164 is an area for storing the number of issued RPCs used in the present embodiment.

The serial number section 165 is an area for storing an issue serial number of the RPC request multiplex message used in the present embodiment. The user data section 166 is an area for storing an input argument for executing a procedure in an RPC request.

[Internal Configuration of Processing Apparatus] Next, an internal configuration of a processing apparatus constituting a distributed system using the remote procedure call processing method according to an embodiment of the present invention will be described with reference to FIG. FIG. 4 is a block diagram of a processing device constituting a distributed system using a remote procedure call processing method according to an embodiment of the present invention.

In the example shown in FIG. 1, the client 22, the server 33, 43, and the nest server, which are component software, are independently provided in each of the processing units 2, 3, 4, and 5. Figure 4
For convenience of explanation, in the processing device 2A, the client 22, the servers 23 and 24, and the nest server 2
5 are collectively possessed.

It should be noted that the processing device 2 A
2, a situation is shown in which one nest server 25 is provided, but a plurality of nest servers 25 may be provided, and some may not be provided.

The RPC processing section 20A is provided with the RP shown in FIG.
It has each function of the C processing units 20, 30, 40, and 50. The RPC processing unit 20A has a communication processing unit 21. The communication processing unit 21 processes communication for transmitting and receiving RPC messages between the client 22 and the servers 23 and 24 in its own processing device 2A, and transmits and receives RPC messages between the servers 23 and 24 and the nest server 25. And further transmits and receives RPC messages to and from clients, servers and nest servers in other processing devices.

The communication processing unit 21 comprises an RPC client processing unit 21A, RPC server processing units 21B, 21C,
It is composed of an RPC nest server processing means 21D. The communication processing unit 21 does not need to have all of these units at the same time, but may have only the units necessary according to the presence or absence of a client, the presence or absence of a server, and the presence or absence of a nest server in the processing device. It is good.

The RPC client processing means 21A corresponds to the processing function in the RPC processing section 20 shown in FIG. The RPC client processing means 21A performs a process of transmitting an RPC request message on behalf of an RPC request from the client 22, and receiving a response message corresponding to the RPC request message. The details will be described later with reference to FIG.

The RPC server processing means 21B corresponds to the processing function in the RPC processing section 30 shown in FIG. R
The PC server processing means 21 B
C request message and the RPC request from the server 23 to the nest server 25
A process for transmitting a request multiplex message and receiving a corresponding response message is performed. The details will be described later with reference to FIGS. 9 and 12.

The RPC server processing means 21C corresponds to the processing function in the RPC processing section 40 shown in FIG. The RPC server processing means 21C processes the RPC request message to the server 24 and
The RPC request to the nest server 25 from the server is transmitted on behalf of the RPC request multiplex message, and the corresponding response message is received.

The RPC nest server processing means 21D corresponds to the processing function in the RPC processing section 50 shown in FIG. The RPC nest server processing means 21D processes an RPC request multiplex message to the nest server. The details will be described later with reference to FIG.

Further, the RPC processing unit 20A includes an address table 100, a transmission information table 110, a transmission / reception information table 120, a nest procedure management table 130, an execution result cache table 140, and an input / output correspondence table 150 as respective management tables. I have.

The address table 100 is stored in the server 23,
24 addresses are managed. Transmission information table 110
Manages information of the transmitted RPC request message.
The transmission / reception information table 120 manages RPC request multiplex message identification information. The nest procedure management table 130 manages the call of the nest server 25. The execution result cache table 140 manages the reception information of the RPC request multiplex message. The input / output correspondence table 150 manages details of the cache information.

The address table 100 and the transmission information table 110 are tables used for the RPC client processing, and correspond to the processing functions in the RPC processing unit 20 shown in FIG. The address table 100 is a table for holding server address information capable of executing a process requested by an RPC request. The details will be described later with reference to FIG. Transmission information table 110
Is a table for holding information of the transmitted RPC request message. The details will be described later with reference to FIG.

The transmission / reception information table 120 and the nest procedure management table 130 are tables used for the RPC server processing, and are the RPC processing units 30 and 4 shown in FIG.
0 corresponds to the processing function. Transmission / reception information table 1
Reference numeral 20 denotes a table for holding information of the received RPC request message. For details, see FIG.
Will be described later. Nest procedure management table 13
0 is a table that holds information on the RPC request requested by the server that has started the process in response to the RPC request message in the process. The details will be described later with reference to FIG.

The execution result cache table 140 and the input / output correspondence table 150 are tables used for the RPC nest server processing, and correspond to the processing functions in the RPC processing unit 50 shown in FIG. The execution result cache table 140 stores an RPC request message from the RPC request message received by the nest server processing unit 21D on the nest server 25 side.
This is a table for determining the PC request multiplex message and managing the number of received PC messages and the cache information, the details of which will be described later with reference to FIG. The input / output correspondence table 150 is a table for storing cache information, and is a table for managing a nest server execution result in response to the input of the RPC request multiplex message. The details will be described later with reference to FIG. . Next, the operation of each unit and the configuration of each table will be described with reference to FIGS. 5 to 16 in accordance with the flow of the RPC process shown in FIGS.

[Client Processing] Client 22
Requests the server to refer to information necessary for processing as necessary, as described above.

Here, the outline of the client RPC request processing according to the embodiment of the present invention will be described with reference to FIG. FIG. 5 is a PAD diagram showing an RPC request process of a client according to an embodiment of the present invention.

In step 201, the client 2
When the server 2 needs to request the server to refer to information necessary for the processing during its own processing, the server 2 issues the request as an RPC request. Here, it is assumed that the client 22 issues an RPC request to the multiplexed servers 23 and 24.

The RPC request is processed in the target servers 23 and 24 via the RPC processing unit 20A. The processing in the servers 23 and 24 will be described later with reference to FIG.

In step 202, the client 2
2 receives the execution result via the RPC processing unit 20A.

Thereafter, its own processing is continued.

[Process of RPC Client Communication Processing Unit] Next, a process performed when the RPC client processing unit of the communication processing unit receives an RPC request from a client will be described with reference to FIG. FIG. 6 is a PAD showing an example of the processing of the RPC client processing means of the communication processing unit according to an embodiment of the present invention. Steps 211 to 215 are processing when transmitting an RPC request message, and steps 216 to 218 are processing when receiving an RPC response message.

In step 211, the communication processing unit 21
The RPC client processing means 21A receives an RPC request from the client 22. At this time, the procedure identifiers of the servers 23 and 24 requested by the client 22 for processing and the procedure input arguments necessary for executing the processing are passed to the RPC client processing unit 21A of the communication processing unit 21.

In step 212, the communication processing unit 21
RPC client processing means 21A of the server 23 capable of executing the request using the address table 100,
24 addresses are obtained. If the server is in another processing device, the server acquires the address of that processing device.
When there are a plurality of executable servers or other processing apparatuses having the executable servers, all the addresses are acquired.

Here, the configuration of the address table 100 will be described with reference to FIG. FIG. 7 is a configuration diagram of an address table in the RPC processing unit according to an embodiment of the present invention.

The address table 100 is a table for holding server address information capable of executing a process requested by an RPC request. Address table 1
00 is the procedure identifier 101 and the address 102
It is composed of

The procedure identifier section 101 stores a procedure identifier representing the processable contents of the server.
The address section 102 stores the address of the server. In the example illustrated in FIG. 7, the process “QSORT” is performed at the address “133.144.8.176:600”.
1 "and" 133.144.8.159:6002 ". In addition, it indicates that the process "MYSWAP" can be executed by the server given by the address "133.144.8.167:6004".

At step 213, the communication processing unit 21
The RPC client processing unit 21A acquires an event identifier. As described above, the event identifier is, for example, an identifier that pairs a processing device number and an event occurrence time, and uniquely identifies an RPC request event from a client or adds the RPC request event to an RPC request message. A request occurrence event can be uniquely specified.

At step 214, the communication processing unit 21
The RPC client processing means 21A creates an RPC request message according to the RPC request message format 160 shown in FIG. At this time, RP
The C control header section 161 stores information necessary for controlling the transmission and reception of the RPC request message, and the execution request procedure identifier section 162 stores the procedure identifier passed from the client 22. The event identifier acquired in step 213 is stored in the event identifier 163, and the number of servers acquired in step 212 is stored in the issued number unit 164. The user data section 166 stores the procedure input argument passed from the client.
At this time, nothing needs to be stored in the serial number part 165.

In step 215, step 214
The RPC request message created at step 212 is transmitted to the processing device having all servers acquired at step 212. For example, for the process "QSORT" shown in FIG. 7, two servers 23 and 24 can be executed, and the servers 23 and 24 are in the own processing device 2A. This is transmitted to the processing means 21B and 21C.

The transmission information is stored in the transmission information table 11
0 is stored. Here, the configuration of the transmission information table 110 will be described with reference to FIG. FIG. 8 is a configuration diagram of a transmission information table in the RPC processing unit according to an embodiment of the present invention.

The transmission information table 110 stores the transmitted RP
It is a table for holding information of a C request message. The transmission information table 110 includes a request procedure identifier unit 111, an event identifier unit 112, and an RPC issuance number unit 113.

The request procedure identifier section 111 stores the procedure identifier of the server that requests processing in the transmitted RPC request message. That is, as shown in FIG.
For example, “QSORT” is stored.

The event identifier 112 contains the transmitted R
The event identifier attached to the PC request message is stored. The event identifier is used by the server to uniquely identify an event in which the client has issued an RPC request. When the event identifier is added to the RPC request message, the receiving side that has received the RPC request message can determine a multiplex message. . That is, RPC from a client
In response to the request, for example, a multiplexing server is started, and a server (nest server) that receives an RPC request from the multiplexing server transmits a multiplexed message from the received RPC request (this is referred to as “RP
C request multiplex message ”). As the event identifier, for example, a numerical value obtained by combining the processing device number and the event occurrence time can be used. In the example shown in FIG. 8, "960419:
123215: 0001 ”, which is composed of“ event occurrence time (year, month, day): client device number + program number: serial number ”. Any event identifier may be used as long as each recipient can be uniquely identified.

The RPC issuance number unit 113 stores the transmitted RP
The number of issued RPCs attached to the C request multiplex message is stored. In the example shown in FIG. 8, the number of issued RPCs is
“2” is stored. This indicates that the execution of the process “QSORT” has been requested to the server “2”.

As described above, in the transmission information table 110, one line is used for each transmitted RPC request message, and the information is cleared when the execution result of the server executed by the message is received as a response message.

Steps 216 to 218 are based on the RPC
This is the process when the response message is received, and these processes will be described later.

[Processing at the time of reception by server processing means] As described above, the servers 23 and 24
2 and may request execution of another server (nest server) in its own processing if necessary. RPC server processing means 21
B and 21C perform RPC reception processing when executing servers 23 and 24 in response to a request from client 22 and RPC transmission processing when servers 23 and 24 request execution of another server (nest server 25). Is what you do.

First, an RPC reception process when executing a server in response to a request from a client will be described.
Referring to FIG. 9, the RPC server processing means of the communication processing unit is R
Processing performed when an RPC request is received from the PC client processing means will be described. FIG. 9 is a PAD diagram showing an example of processing at the time of reception by the RPC server processing means of the communication processing unit according to an embodiment of the present invention.

In step 221, the communication processing unit 21
RPC server processing means 21B and 21C receive the RPC request message.

In step 222, the communication processing unit 21
The RPC server processing means 21B, 21C of the RPC request message stores the request procedure identifier, the event identifier and the value of the number of issued RPCs added to the RPC request message in the request procedure identifier section 12 of the transmission / reception information table 120, respectively.
1, the event identifier section 122 and the RPC issue number section 123 are written.

Here, the configuration of the transmission / reception information table will be described with reference to FIG. FIG. 10 is a configuration diagram of a transmission / reception information table in the RPC processing unit according to an embodiment of the present invention.

The transmission / reception information table 120 stores the received R
It is a table for holding information of a PC request message. The RPC processing unit 20A has one transmission / reception information table. The transmission / reception information table 120 includes a request procedure identifier section 121, an event identifier section 122,
It is composed of an RPC issue number unit 123 and a nest procedure management table management unit 124.

The request procedure identifier section 121 stores the procedure identifier requested to be processed by the received RPC request message. The event identifier 122 stores an event identifier attached to the received RPC request message.

The RPC issuance number section 123 contains the received RP
The number of issued RPCs attached to the C request multiplex message is stored. The nest procedure management table management unit 124 stores the address of the nest procedure management table 130.

The nest procedure management table 130 is
This is a management table used when an execution request is issued from the server to the nest server, the details of which will be described later with reference to FIG.

In the example shown in FIG. 10, an RPC request message requesting the process “QSORT” is received, and the message is “960419: 123215: 000”.
This is caused by the event identified by “1”, and “two” RPC request messages are transmitted by the event.

Further, information on the RPC called during the execution of the server is stored in the nested procedure management table 130 at the address “0x00200000”.

As described above, in the transmission / reception information table 120, one line is used for each received RPC request message, and the information is cleared when the execution result of the server executed by the message is transmitted as a response message.

Next, in step 223, the RPC server processing means 21B and 21C of the communication processing unit 21 execute the requested server.

In step 224, when the execution of the server is completed, the RPC server processing unit 2 of the communication processing unit 21
1B and 21C receive the execution result.

In step 225, the communication processing unit 21
RPC server processing means 21B and 21C create an RPC response message to which the execution result is added.

Next, in step 226, the RPC server processing means 21B, 21C of the communication processing unit 21 transmits an RPC response message to the requesting client.

In step 227, the communication processing unit 21
The RPC server processing units 21B and 21C clear information stored in the request identifier unit 121, the event identifier unit 122, and the RPC issue number unit 123 of the transmission / reception information table 120.

Further, in step 228, if the address of the nest procedure management table is stored in the nest procedure management table management section 124, the RPC server processing means 21B, 21C of the communication processing section 21 stores the address information. Clear and clear all the information in the nested procedure management table.

[Process of Server] Next, referring to FIG.
The processing of the server when the server is executed by the RPC request will be described. FIG. 11 is a PAD showing the processing contents of the server in the processing device according to the embodiment of the present invention.

The servers 23 and 24 execute their own processing in response to a request from the client or the server, and return the execution result to the calling client via the RPC processing unit. Further, if necessary, other servers (nest servers 25) may be requested to refer to information necessary for processing, similarly to the client 22.

In step 231, the servers 23, 2
4 receives a server execution request from the RPC server processing units 21B and 21C of the RPC processing unit that has received the RPC request message.

At step 232, its own process is executed.

Until the execution is completed (step 233), in step 234, the servers 23 and 24 execute the processing.

At step 235, the servers 23, 2
4 is another server (nest server 25) in the processing.
It is necessary to refer to some information for
Determine whether there is a request.

If there is an RPC request, in step 236, the servers 23 and 24 issue an RPC request.

Then, in step 237, the servers 23 and 24 receive the execution results.

In step 233, if necessary, the servers 23 and 24 start executing their own processes again.

At step 238, the servers 23, 2
When the execution of the server ends, the server 4 passes the execution result to the server processing units 21B and 21C of the communication processing unit 21 of the RPC processing unit 20A.

As described above, the servers 23 and 24 may issue any number of RPCs to another server during their own processing.

[Processing at the time of transmission by server processing means] FIG.
Server 2 as described in step 236 of FIG.
3, 24 need to refer to some information to another server (nest server 25) during the processing,
If there is an RPC request, it issues an RPC request. The process of issuing the RPC request is performed by the server processing units 21B and 21C.

Therefore, referring to FIG.
A process performed by the PC server processing unit when transmitting an RPC request message in response to an RPC request will be described. FIG. 12 is a diagram illustrating the RPC of the communication processing unit according to an embodiment of the present invention.
FIG. 9 is a PAD diagram showing an example of processing at the time of transmission by a server processing means.

In step 241, the communication processing unit 21
Server processing means 21B, 21C
If the server 23 or 24 issues an RPC request to another server (nest server 25) during the execution of, the RPC request is accepted.

At this time, the procedure identifiers of the nest server 25 requested by the servers 23 and 24 for processing and the procedure input arguments necessary for executing the processing are passed to the server processing means 21B and 21C of the communication processing unit 21.

At step 242, the communication processing unit 21
The server processing means 21B, 21C of the above uses the address table 100 to acquire the address of the nest server that can execute the request.

At step 243, the communication processing unit 21
Server processing means 21B, 21C of the own server 23, 24 of the transmission / reception information table 120 shown in FIG.
The nested procedure management table 130 given by the address in the nested procedure management table management unit 124 corresponding to the procedure identifier is searched.

Here, the configuration of the nest procedure management table 130 will be described with reference to FIG. FIG.
FIG. 6 is a configuration diagram of a nest procedure management table in the RPC processing unit according to an embodiment of the present invention.

The nest procedure management table 130 is
9 is a table that holds information on an RPC request requested by a server that has started processing by an RPC request message during the processing.

The RPC processor 20A has a plurality of nest procedure management tables. The nest procedure management table may be prepared in advance for a certain fixed number and acquired from the table when necessary. Alternatively, the table may be created by dynamically allocating memory when necessary.

The nest procedure management table 130 is
Nest procedure identifier section 131 and address section 132
And a serial number 133.

In the nested procedure identifier 131, R
Server 2 that started processing by PC request message
3 and 24 store the procedure identifier (hereinafter, referred to as “nest procedure identifier”) of the server (nest server 25) that can execute the process requested by the RPC in the process.

The address of the nest server 25 is stored in the address section 132. The serial number unit 133 stores a serial number indicating the number of times the nest server 25 has been called. The same nested server process may be required a plurality of times for one server execution. The serial number starts counting for one server execution, and is cleared when the execution of the server ends.

The transmission / reception information table 120 shown in FIG.
In the nested procedure management table management unit 124, for example, the nested procedure management table 130 of the address designated by the address “0x00200000”
The nest procedure information about the RPC called during the execution of the server is stored.

As shown in FIG. 13, in the nest procedure management table 130, the RPC request message “QSAVE” has the address “133.14”.
4.8.192: 6008 ". This table is released (cleared) when it is no longer needed, that is, when the server has finished executing.

In step 243, the communication processing unit 21
If there is no nested procedure management table corresponding to the nested procedure identifier of the RPC request to be issued and the address to which the message is transmitted, the server processing means 21B, 21C secures or creates an unused nested procedure management table. Then, the head address is written to the nested procedure management table management unit 124, the nested procedure identifier for the RPC request is written to the nested procedure identifier unit 131 of the nested procedure management table 130, and the destination to which the message is transmitted is written to the address unit 132. The address is written, and the value “1” is set in the serial number unit 133.

At step 243, the RP to be issued is
If there is a nested procedure management table corresponding to the nested procedure identifier of the C request and the address to which the message is to be transmitted, the server processing units 21B and 21C of the communication processing unit 21 will execute the nested procedure management table 1
Using 30, the nest procedure identifier of the RPC request to be issued and the serial number unit 133 corresponding to the address to which the message is transmitted are searched, and the value of the serial number is incremented.

In step 244, the communication processing unit 21
Server processing means 21B, 21C of the nest server 25
An RPC request multiplex message to be transmitted to the server is created according to the RPC request message format 160 shown in FIG.

At this time, the information necessary for controlling the transmission and reception of the RPC request message is stored in the RPC control header section 161, and the procedure of the nest server 25 passed from the servers 23 and 24 is stored in the execution request procedure identifier section 162. Stores the identifier. For example, “QSAVE” is stored as the procedure identifier.

The event identifier section 163 stores an event identifier corresponding to its own procedure identifier in the transmission / reception information table 120, and the issue number section 164 stores an RPC issue number corresponding to its own procedure identifier in the transmission / reception information table 120. Store the value of.

The user data section 166 stores the procedure input argument passed from the server 23 and stores the serial number section 165
Includes a nested procedure management table 130 corresponding to its own procedure identifier in the transmission / reception information table 120.
The value of the serial number stored in the serial number unit 133 corresponding to the nested procedure identifier that is requested to be executed and the destination address is stored.

Next, in step 245, the server processing means 21B and 21C of the communication processing unit 21
The RPC request multiplex message created in step 44 is transmitted to the nest server 25 acquired in step 242.

Steps 246 and 247 are processing at the time of response for receiving the execution result from the nest server 25, and these will be described later.

[Process of Nest Server Processing Unit] Next, the process of the nest server processing unit 21D that has received the RPC multiplex request message transmitted from the server processing units 21B and 21C will be described with reference to FIG. FIG.
FIG. 9 is a PAD diagram showing an example of a process performed when a nest server processing unit of the communication processing unit receives an RPC request multiplex message according to an embodiment of the present invention.

Since the server processing means 21B and 21C are multiplexed, the nest server processing means 21D receives the same RPC request message twice each of the server processing means 21B and the server processing means 21C. The nest server processing means 21D performs different processings on the first received RPC request message and the second and subsequent received RPC request messages.

In step 251, the nest server processing means 21D receives the RPC request multiplex message from the servers 23 and 24.

At step 252, the nest server processing means 21D acquires the input / output correspondence table 150 corresponding to the received RPC request multiplex message.

Here, the address of the input / output correspondence management table 150 in which the request procedure identifier and the event identifier of the received RPC request multiplex message are equal to the request procedure identifier and the event identifier held in the execution result cache table 140 are set. As a result, the input / output correspondence table 150 corresponding to the received RPC request multiplex message is acquired.

Here, the configuration of the execution result cache table 140 will be described with reference to FIG. FIG.
FIG. 6 is a configuration diagram of an execution result cache table in the RPC processing unit according to an embodiment of the present invention.

The execution result cache table 140 is used by the nest server processing means 21D of the nest server 25 to determine the RPC request multiplex message from the received RPC request messages, and to manage the number of received RPC request messages and the cache information. It is a table. The nest server processing unit 21D of the RPC processing unit 20A has one execution result cache table.

The execution result cache table 140 includes a request procedure identifier section 141 and an event identifier section 14.
2, RPC issuance number section 143, and reception counter section 144
And an input / output correspondence table management unit 145.

The request procedure identifier section 141 stores the identifier of the procedure requested to be processed by the RPC request multiplex message received by the nest server 25. The event identifier 142 includes the R received by the nest server 25.
The event identifier attached to the PC request message is stored.

The RPC issuance number section 143 includes the RP attached to the RPC request message received by the nest server 25.
The value of the number of issued C is stored. The nest server 25 receives RPC request multiplex messages having the same event identifier for the number of issued RPCs.

The reception counter 144 stores a counter value for counting the number of received RPC request multiplex messages having the same event identifier. The input / output correspondence table management unit 145 stores the address of the input / output correspondence table 150.

As described above, in the execution result cache table 140, one row is used for each set of the procedure identifier and the event identifier of the nest server 25.

In the example shown in FIG. 15, "QSORT" is stored as the request procedure identifier section 141, and "960419: 12321" is stored as the event identifier section 142.
5: 0001 ”is stored, and“ 2 ”is stored as the RPC issuance number part 143.
“1” is stored, and the input / output correspondence table management unit 145 is stored.
"0x00208000" is stored. That is, if the request procedure identifier is “QS
ORT "and the event identifier part 142 is" 9604 ".
19: 123215: 0001 "procedure
The number of issuance is "2", and out of these two RPCs,
“1” procedures indicated by the reception counter have been received, and as the execution result of the procedures, the address “0x
00208000 "indicates that an input / output correspondence table is formed.

Next, the configuration of the input / output correspondence table 150 will be described with reference to FIG. FIG. 16 is a configuration diagram of an input / output correspondence table in the RPC processing unit according to an embodiment of the present invention.

The input / output correspondence table 150 is a table for storing cache information, and is a table for managing a nest server execution result with respect to the input of the RPC request multiplex message. The nest server processing means 21D of the RPC processing unit 20A has a plurality of input / output correspondence tables.

The input / output correspondence table 150 may be prepared in advance for a fixed number, and may be obtained from the table when necessary. However, it is also possible to prepare a table by dynamically allocating memory when necessary. Good thing.

The input / output correspondence table 150 is used when the RPC is no longer needed, that is, the RPC associated with the set of the procedure identifier and the event identifier of the nest server 25.
Released when all request multiplex messages have been received.

As the input / output correspondence table 150, one input / output correspondence table is used for each set of the procedure identifier and the event identifier of the nest server 25. One input-output correspondence table 150 is generated and managed for each identical RPC request multiplex message.

The input / output correspondence table 150 includes an input argument section 151 for storing an input argument and an execution result section 152 for storing the execution result of the nest server 25 corresponding to the input argument section.

Here, returning to the PAD diagram shown in FIG. 14, in step 253, the nest server processing means 2
1D determines whether there is a request procedure identifier and an event identifier corresponding to the execution result cache table 140, and if not, proceeds to step 254. That is, the nest server processing means 21D determines whether the received RPC request multiplex message is the first RPC request message,
Alternatively, the second and subsequent RPC request messages are determined, and if it is the first RPC request message, step 2
Proceed to 54.

In step 254, the nest server processing means 21D writes the request procedure identifier, the event identifier, and the number of issued RPCs of the received RPC request multiplex message into the execution result cache table 140.

In step 255, the nest server processing means 21 D secures or creates an unused input / output correspondence management table 150, and stores the leading address in the input / output correspondence table management unit 145 of the execution result cache table 140. Write.

Next, in step 256, the nest server processing means 21D refers to the obtained input / output correspondence table 150 and finds the same input argument as the procedure input argument stored in the user data section 166 of the received RPC multiplex request message. It is checked whether there is, and if so, step 257
If no, go to step 260. That is, the nest server processing unit 21D determines whether or not the received RPC request message has already been executed in the server 25. When the second and subsequent RPC request messages are received, the process proceeds to step 257, and when the first RPC request message is received, the process proceeds to step 260.

In step 256, if the input argument is a set of a plurality of arguments, it is checked whether or not there is an input argument in which all the corresponding sets of arguments are equal.

At step 257, the nest server processing means 21D determines that the execution result corresponding to the input argument is
It is checked whether or not the data is written in the execution result section 152 of the input / output correspondence table 150.

If the data has not been written, the nest server processing means 21D waits at step 258 until the data has been written. In other words, at this point, although another RPC request message has already been received, the nest server 2 for that RPC request message has
Since the processing of No. 5 has not been completed, it waits for the execution result to be written. When written, step 259
Proceed to.

At step 259, the nest server processing means 21D acquires the execution result corresponding to the input argument. That is, when receiving the second and subsequent RPC request messages, the nest server processing means 21D acquires only the execution result without the server 25 repeatedly executing the same request.

On the other hand, if there is not the same input argument in step 256, in step 260, the nest server processing means 21D determines that the arriving message is the first of a set of RPC request multiplex messages, and The input argument attached to the received RPC request message is written into the input argument section 151 of the table 150.

In step 261, the nest server 2
Step 5 is executed. The execution process of the nest server 25 will be described later.

In step 262, the nest server processing means 21D acquires the execution result of the nest server 25.

Then, in step 263, the nest server processing means 21D writes the execution result as cache information in the execution result section 152 corresponding to the input argument of the input / output correspondence table 150 written in step 260.

Next, in step 264, the nest server processing means 21D creates an RPC response message to which the execution result of the nest server obtained in step 259 or 262 is added.

In step 265, the nest server processing means 21D adds the nest server execution result to the R
A PC response message is transmitted to the server that issued the RPC request. That is, here, the RPC response message is transmitted to either the server processing unit 21B or the server processing unit 21C according to the received RPC request message.

Next, at step 266, the nest server processing means 21D increments the value of the reception counter 144 of the execution result cache table 140 in order to manage the cache information in the communication processing section 21. The number of received RPC request multiplex messages generated from the same event is counted.

Next, at step 267, the nest server processing means 21D checks the RP generated from the same event.
In order to determine whether or not all the C request multiplex messages have been received, the counter value incremented in step 266 is compared with the value of the RPC issue number section 143 of the execution result cache table 140.

If they are equal, in step 268, the nest server processing means 21D clears the event identifier, the number of issued RPCs, and the reception counter value in the execution result cache table 140.

Further, in step 269, the nest server processing means 21D releases the input / output correspondence table 150.

As described above, the cache information includes the execution result cache table 140 and the input / output correspondence table 1
50, one row of the execution result cache table and one input / output correspondence table are secured when the first message of the set of RPC request multiplex messages is received, and all RPC request multiplex messages of the set are stored. It is released immediately after receiving and returning the execution result.

The number of RPCs depends on the number of RPCs issued.
Since it is possible to know whether to receive the request message, the cache information can be released immediately when the number of received request messages has been received, so that it is possible to avoid holding the cache information forever and consuming a lot of memory. it can.

[Server Processing] Next, the nest server 25
Will be described.

The nest server 25 is the same as the nest server 50 described above, executes its own processing in response to a request from the server, and returns the execution result to the calling server via the RPC processing unit. It is. If necessary, the client 2 refers to information necessary for processing.
Similarly to 2, the request may be made to another server.
The processing of the nest server 25 is the same as the processing of the server 23 described in FIG.

[Process at the time of response from the nest server processing means]
When the nest server 25 is executed and an execution result is obtained,
The nest server processing unit 21D returns the execution result to the server processing units 21B and 21C, and the processing at that time is as described in steps 264 and 265 of FIG.

[Process at the time of response from server processing means]
The processing at the time of the response of the server processing means 21B and 21C when receiving the execution result from the nest server 25 will be described with reference to FIG.

In step 246, the communication processing unit 21
Receive the RPC response message corresponding to the called nest server 25.

At step 247, the communication processing section 21
Server processing means 21B and 21C return the execution result added to the received RPC response message to the calling server 23.

The processing at the time of the response of the server processing means 21B, 2C when the execution of the servers 23, 24 itself is completed is as described in FIG.

In step 224 of FIG. 9, when the execution of the server is completed, the RPC server processing units 21B and 21C of the communication processing unit 21 receive the execution results.

At step 225, the communication processing unit 21
RPC server processing means 21B and 21C create an RPC response message to which the execution result is added.

Next, in step 226, the RPC server processing means 21B, 21C of the communication processing section 21 transmits an RPC response message to the requesting client.

[Processing at Response of Client Processing Unit]
Next, the processing at the time of response of the client processing means 21A when receiving the execution result from the servers 23 and 24 will be described.
This will be described with reference to FIG.

At step 216, all RPC response messages for the number of called servers are received.

In step 217, after all the RPC response messages have been received, one of the received RPC response messages is selected at random, for example.

Further, in step 218, the result of execution of the server attached to the message is returned to the requesting client 22.

The method of waiting for the RPC response message in step 216 and the method of selecting the RPC response message in step 217 are not limited to the above. For example, a method of returning one of the first received messages or a method of receiving an RPC response message within a certain time period Various methods such as selecting one using majority logic according to the contents of the response can be used.

[Processing when Client Responds] Next, processing when the client 22 responds when the client processing means 21A receives execution results from the servers 23 and 24 will be described.

As described with reference to FIG.
02, the client 22 returns the execution result to R
Received via PC processing unit 20A.

As described above, in the present embodiment, the processing device on the nest server side (the nest server processing means of the communication processing unit 21 of the RPC processing unit 20A) transmits the detected message relating to the same process and the execution result. By managing the nest server itself, the number of executions of the nest server can be suppressed. Therefore, for example, in order to realize a fault, the multiplexing of servers or the N-version of servers are performed.
When nesting servers are called in parallel by multiplexing using the on-programming technique, and another procedure request is issued from the multiplexed server, the nest server that receives the procedure request receives the procedure request according to the request content. The actual number of procedure executions can be reduced, and the load on the nest server-side processing device can be reduced.

As a result, the RPC response time can be shortened.

Further, the nest server which receives the procedure execution request from the multiplexing server can know in advance the number of multiplexed messages to be received belonging to the same process. The storage period and the size of the cache memory can be effectively controlled. In particular, when realizing a three-layer client / server model that is becoming popular as a system construction model of a client / server type system, when multiplexing a procedure execution unit (server) that plays a role of its function layer, a response time is required. This is effective in reducing the load on the procedure execution unit (server) in the data layer, and also in the storage period of the cache contents,
The size of the cache memory can be suitably controlled.

Further, the nest server 25 can perform its own processing without being aware of the number (multiplicity) of processing units of the transmission source that transmits multiplex messages related to the same processing. Is improved.

Further, even if the multiplicity of the server is changed during online operation, the nest server is not affected. Therefore, the server can be multiplexed at the required multiplicity when necessary, and the reliability can be improved. . That is, in the conventional method, it is necessary to design the client of the presentation layer or the server program of the data layer in consideration of the number of servers of the function layer in advance. However, if the number of functions in the function layer server is increased or decreased and the number changes, it is necessary to redesign the presentation layer client or data layer server program in consideration of the fluctuation. there were. In addition, even if a failure occurs in the function layer server, the number will fluctuate. Therefore, it is necessary to design the program of the presentation layer client or the data layer server in advance in consideration of the fluctuation in the number. There has been a problem that the program design is complicated and development efficiency is deteriorated. However, as described above, even if the multiplicity of a server is changed during online operation, the nested server is not affected, so that the server can be multiplexed at the required multiplicity when necessary, thereby improving reliability. Can be.

At this time, RPs having the same input argument
Since the multiplexing server that sends the C request message can receive the same processing result, asynchronous parallel execution of the multiplexing server becomes possible, and reliability and maintainability are improved.

In the above description, the servers 23, 2
4 is a multiplexed server, but the present invention is not limited to this. For example, servers of different versions may be used. For example, when it is desired to perform a system operation in which a new version server is added and an old version server is deleted after using only one old version server, the caller client 22, server 23, The nest server 24 and the nest server 25 may perform their own processes without being aware that the servers 23 and 24 are operating as described above, and it is not necessary to design a program in consideration of the operation mode in advance. Therefore, it becomes possible to operate such a server, and it is possible to improve program development efficiency and system online maintainability.

Note that the server returns information obtained by processing or integrating information received from the nest server to the client, while a new version of the server transmits new quality information using a new processing method or a new integration method. It may be created and returned to the client. At this time, by replacing the old and new versions of the server described above, the client can acquire new quality information. Even in this case, each of the client, the server, and the nest server does not need to carry out a program design in advance in consideration of replacing the server of the new and old versions described above.
Even during the online processing, each of the client, the server, and the nest server does not need to be conscious of replacing the server of the old and new versions, and can continue the execution.

Note that the input / output correspondence table 150 shown in FIG. 16 has only one row, and in the nest server processing shown in FIG. 14, input arguments must be written exceeding the number of rows in this table. When it is gone, its R
The PC request may be returned to the processing device of the requesting server as an error. Therefore, in FIG. 14, the processing from step 260 to step 263 is deleted, and instead, the RPC request is returned as an error, so that, for example, processing for acquiring an error code as an execution result is performed. With this, even if the input arguments are different between the RPC request multiplex messages belonging to the same process, the nest server can be executed using only one of them, so that even if the multiplicity of the server is changed, the nest server will The processing will not be affected. Therefore, also in this case, asynchronous parallel execution of the multiplex server becomes possible, and reliability and maintainability are improved.

A name server, which is a processing device for managing addresses of servers and nest servers, may be provided in the present system. This name server manages the correspondence between the procedure identifiers of the servers and nest servers in the system and the addresses, and registers the addresses of the servers and nest servers according to requests from programs such as clients, and addresses according to requests. Has the function to return.

Using this, in the system configuration shown in FIG.
The procedure for adding a new server is as follows. First, the procedure identifier of this additional server and its address are registered in the name server. This procedure identifier is assumed to be the same as that of the servers 23 and 24 now. Next, when an RPC request is issued from the client 22, the RPC processing unit 20A
Obtains all the addresses of the server having the procedure identifier corresponding to the process requested from the name server. R
The PC processing unit 20A sends an RPC request message to the acquired processing devices of all servers. Hereinafter, by performing the processing described so far, a series of R
PC processing is executed.

Further, in the nest server processing in the nest server processing means 21D shown in FIG.
When the ES is determined to be ES, in steps 257 to 259, the execution result for the first RPC request is obtained, and this execution result is transmitted in step 265. Alternatively, the information indicating that the process was not executed may be included in the RPC response message in step 265 without executing the process.

According to the present embodiment, the load on the nest server-side processing device can be reduced.

As a result, the RPC response time can be shortened.

When the procedure execution unit (server) is multiplexed, it is effective for shortening the response time and suppressing the load on the procedure execution unit (server) in the data layer. The size of the memory can be suitably controlled.

Also, the program development efficiency of the nest server is improved.

Further, the servers can be multiplexed at the required multiplicity when necessary, and the reliability can be improved.

Further, asynchronous parallel execution of the multiplex server becomes possible, and reliability and maintainability are improved.

Next, a remote procedure call processing method according to another embodiment of the present invention will be described with reference to FIGS. In the remote procedure call processing method according to the above-described embodiment, when there are a plurality of servers called by a client, the processing device (processing means) of the client sends an RPC request message directly to the processing devices (processing means) of the plurality of servers. The "multicast method" for transmission was used. However, in the present embodiment, the processing device (processing means) of the client
Transmits an RPC request message to an arbitrary one of the processing devices (processing means) of the plurality of servers, and the processing device (processing means) receiving the message transmits the RPC request message to the remaining server. RPC for processing equipment (processing means)
A multicast method for dispatching a request message (hereinafter referred to as an "indirect multicast method") is used. This indirect multicast method is effective, for example, when there is a master / slave relationship between multiplexed servers. In the indirect multicast scheme, all clients send only the master server
The master server sends a PC request message, and the master server sends the received RPC request message to all its slave servers, so that the RPC request message sent from the client is delivered to all the multiplexing servers, Multiple execution of servers becomes possible. As described above, in the indirect multicast method, the server is only one, without the client being aware of the multiplicity of the server.
There is an advantage that the RPC request message can be transmitted and the RPC response message can be received as if it were one.

Here, a distributed system using a remote procedure call processing method according to another embodiment of the present invention will be described with reference to FIG. FIG. 17 is a block diagram showing the overall configuration of a distributed system using a remote procedure call processing method according to another embodiment of the present invention. The same reference numerals as those in FIG. 1 indicate the same parts.

In FIG. 17, communication medium 1, processing device 2
5, client 22, servers 33 and 43, nest server 53, and RPC processors 20, 30, 40 and 50 are the same as those in FIG. A communication medium 1 and a processing device 2
5, the client 22, the servers 33 and 43, the nest server 53, and the RPC processing units 20, 30, 40 and 50 can be collectively arranged in one processing device as described in FIG. It is.

[0212] The arrows in the figure indicate that the RPC request message generated from the client 22 indirectly multicasts the RPC request message to execute the servers 33 and 43, and the RPC request generated during the execution of the respective servers 33 and 43. The flow of a series of RPC requests that the nest server 53 is executed is shown.

FIG. 17 shows the flow of an RPC request when the servers 33 and 43 are in a master / slave relationship, and the server 33 is a master server and the server 43 is a slave server.

Here, the overall flow at the time of an RPC execution request in the remote procedure call processing method according to the present embodiment will be described using the arrows shown in FIG.
When an RPC request is issued from the client 22 (arrow 81), the RPC processing unit 20 acquires an address of a processing device of a server that can execute the processing. In the present embodiment, there are two corresponding processing devices 3 and 4, but only one of the processing devices 3 is acquired as the address of the master server, and an RPC request message is transmitted to that server (arrow). 82a).

Here, this RPC request message includes information such as an event identifier for identifying an event in which an RPC request has been issued from the client, the number of issued RPCs, and a dispatch flag indicating that the message is an RPC request message to the master server. In. The dispatch flag will be described later with reference to FIG.

Upon receiving the RPC request message, the RPC processing unit 30 of the processing device 3 checks the received dispatch flag, and if it knows that the message is to be transmitted to the master server 33, copies the contents of the RPC request message. The data is transmitted to the slave server 43 (arrow 82b). Thus, the RPC request message is passed to the master server 33 and the slave server 43, and each server stores the event identifier and the RPC issuance attached to the message,
The servers 33 and 43 are executed (arrows 83a and 83b).

When each of the servers 33 and 43 issues an RPC request to another server (nest server 53) (arrows 84a and 84b), the RPC processing units 30 and 40
The stored event identifier and the number of issued RPCs are
The message is added to the PC request multiplex message and transmitted to the processing device 5 of the nest server (arrows 85a, 8a).
5b).

In the processing device 5 that receives this RPC request multiplex message, the RPC processing unit 50 sends the RP
RP generated by the same event from the client based on the event identifier from the C request multiplex message
The C request multiplex message is determined, and the first one is selected from among them, and the nest server 53 is executed (arrow 86).

Next, the overall flow of an RPC response in the remote procedure call processing method according to the present embodiment will be described with reference to FIG. FIG. 18 is a block diagram showing the overall configuration of a distributed system using a remote procedure call processing method according to another embodiment of the present invention.

The execution result of the nest server 53 and the input argument therefor become cache information of the nest server.
It is stored in the PC processing unit 50 (arrow 87). Remaining RP
The nest server 53 is not executed in the C-request multiplex message. When the cache information of the execution result is found and there is an equal input argument, the execution result information is returned to the caller as the execution result as it is. If there is no equal input argument, execute the nest server using that input argument. The execution result also becomes cache information. However, R for the number of RPCs issued on the client side
PC request multiplex message (has the same event identifier)
Is received, the cache information is cleared.

The RPC response message is passed to the RPC processing units 30 and 40 of the calling servers 33 and 43 (arrows 88a and 88b), and the execution result is passed to the servers 33 and 43 being executed (arrows 89a and 89b). . The execution result of the server is returned to the RPC processing units 30 and 40 for returning to the calling client 61 (arrows 90a and 90).
b).

Here, the RPC processing unit 40 of the slave server 43 returns an RPC response message to the RPC processing unit 30 of the master server 33.
A C response message is created and returned to the processing device of the RPC processing unit 30. The RPC processing unit 30 selects one of the execution result of its own server and the execution result attached to the received RPC response message by a predetermined selection unit, and returns it to the client as an execution result. An RPC response message is created and returned to the processing device of the calling client 22 (arrows 71a, 71).
1b). The logic of this selection is step 2 in FIG.
The selection logic described in 17 can be used.

Next, referring to FIG. 19, the processing units 2, 3,
The format of the RPC request message transmitted between the communication media 4 and 5 via the communication medium 1 will be described. FIG.
FIG. 7 is an explanatory diagram of a format of an RPC request message transmitted in a remote procedure call processing method according to another embodiment of the present invention.

RPC request message format 160
Is the RPC control header 161 and the event identifier 16
3, an issue number part 164, a serial number part 165, and a user data part 166.

Further, in the present embodiment, in the RPC request message format 160, a dispatch flag section 167 is newly provided in the RPC control header 161. The dispatch flag unit 167 has a flag for identifying whether the RPC request message is an RPC request message transmitted from the client to the master server or an RPC request message transmitted from the master server to the slave server. Is stored.

That is, for example, an RPC request message transmitted from the client 22 to the server 33 is a transmission message to the master server. Therefore, the dispatch flag section 167 of the RPC request message includes
"1" is stored. Since the RPC request message transmitted from the RPC processing unit 30 of the processing device 3 that has received the RPC request message to the server 43 is a message transmitted to the slave server, the dispatch flag unit 167 of the RPC request message includes “ "0" is stored. The RPC processing unit of the receiving server determines whether or not dispatch transmission to the slave server is necessary, based on the contents of the dispatch unit 167 of the received RPC request message.

Next, with respect to the processing of the communication processing unit in the RPC processing unit, only the parts different from the embodiment shown in FIG. 4 will be described. The communication processing unit 20A shown in FIG. 4 includes an RPC client processing unit 21A and an RPC server processing unit 21.
B, 21C and RPC nest server processing means 21D. In this embodiment, the processing of the RPC client processing unit and the processing of the RPC server processing unit are slightly different.

First, the RPC client processing means 21A
The changed part of will be described. FIG. 60 is a PAD showing the contents of the RPC client processing performed by the RPC client processing means 21A of the communication processing unit, which will be described with reference to FIG.

In this embodiment, in step 212, the RPC client processing means 21A acquires the address of only one server. There are various server selection methods for this acquisition. For example, they may be selected randomly or may be uniquely determined in advance.

At step 214, RPC
The client processing unit 21A creates an RPC request message to be sent to the server. At this time, the dispatch flag unit 167 of the RPC request message indicates that the transmission is from the client to the master server. The value “1” is stored.

At step 215, RPC
The client processing means 21A transmits the RPC request message only to the one server.

At step 216, the RPC client processing means 21A receives one RPC response message, and returns the execution result to the client at step 218 without executing step 217.

Next, the RPC server processing means 21B, 21
The changed part of C will be described. FIG. 9 is a PAD showing the contents of the RPC server processing performed by the RPC server processing means 21B and 21C of the communication processing unit, and will be described with reference to FIG. Here, the RPC server processing means 21B is the processing means of the master server, and the RPC server processing means 2
1C will be described as processing means of the slave server.

At step 221, upon receiving the RPC request message, RPC server processing means 21B
First, the dispatch flag unit 16 of the RPC request message
7 to determine whether the transmission is from the client to the master server or from the master server to the slave server.

If it is determined that the transmission is from the client to the master server, the event identifier section 163, the number of issued sections 164,
The contents of the user data section 166 and the execution request procedure section 162 are copied as they are, and the dispatch flag section 1
A new RPC request message in which the content of 67 is rewritten to “0” indicating transmission from the master server to the slave server is transmitted to the RPC server processing unit 21C. The transmission destination is the address table 1 managed by itself.
Determined using 00.

Thereafter, the flow advances to the next step 222.

Further, in an added step after step 224, RPC server processing means 21B receives all the RPC response messages from RPC server processing means 21C of the slave server which transmitted the RPC request message in step 221. One execution result is selected from the execution result of its own server and the received RPC response message based on a predetermined selection logic.

At step 225, the RPC server processing means 21B adds the selected execution result to the RPC response message returned to the client.

The flow of processing in the RPC server processing means 21C is as shown in the PAD diagram of FIG. 9. If it is determined in step 221 that the transmission is from the master server to the slave server, the flow proceeds to step S221. 2
Go to 22.

With the above-described processing, the remote procedure call processing according to the present embodiment is performed.

According to the present embodiment, the load on the nest server-side processing device can be reduced.

As a result, the RPC response time can be shortened.

When the procedure execution unit (server) is multiplexed, it is effective to reduce the response time and the load on the procedure execution unit (server) in the data layer. The size of the memory can be suitably controlled.

In addition, the program development efficiency of the nest server is improved.

Further, servers can be multiplexed at a required multiplicity when required, and reliability can be improved.

In addition, asynchronous parallel execution of the multiplex server becomes possible, improving reliability and maintainability.

Further, in the embodiment, the present invention can be applied particularly to a master / slave type multiplex server as a server multiplex mode.

In this embodiment, the server 3
Although the servers 3 and 43 are multiplexed servers, the present invention is not limited to this. For example, servers of different versions may be used. Also in the present embodiment, when it is desired to perform a system operation in which a new version server is added and an old version server is deleted after using only one old version server, the client 22 on the calling side is used. , Servers 33 and 43, and nest server 53
It is only necessary to perform its own processing without being aware that the program is operated as described above, and it is not necessary to design a program in consideration of the above-mentioned operation mode in advance. This allows
Program development efficiency can be improved.

Also in the present embodiment, a name server which is a processing device for managing addresses of servers and nest servers may be provided in the present system.

Although the embodiments of the present invention have been described in detail, the embodiments of the present invention are not limited to those described here, and various modifications may be made without departing from the spirit of the present invention. Obviously, you get it.
For example, although the embodiment using the remote procedure call as the communication method between the processing devices has been described, any communication means that performs a request / response can be used instead of the remote procedure call.

Although the nest server has been provided in the form of a procedure, the nest server need not be in the form of a procedure as long as the program performs its own processing in response to a request and returns the execution result. . Further, the execution result may not be returned.

The embodiments of the present invention include the following.

1) In a remote procedure call processing method in a distributed system in which a plurality of processing means have a hierarchical structure of three or more layers, processing means on the procedure execution side are multiplexed, and these processing means are connected by a transmission network, The processing means having received the call request message detects a multiplex request message based on the contents of the user data portion included in the remote procedure call request message, selects one of the multiplex request messages, and selects the selected multiplex request message. Executes its own process using the message, returns the execution result to the transmission source processing device of the selected multiplex request message, and sends a request to the transmission source processing device of the multiplex request message selected by the selection. Returns information that the requested operation was not performed, Remote information managing the cache information for the multiplexed remote procedure call request based on information on the number of processing means of the destination requesting the remote procedure call included in the remote procedure call request message. Procedure call processing method.

2) In the remote procedure call processing method described in 1) above, the multiplicity of the server program is changed by adding or deleting processing means having the server program online. .

3) In the remote procedure call processing method described in 1) above, the first server program included in the processing means for executing its own processing in response to the remote procedure call from the processing means requesting the remote procedure call; A second server program that performs the same processing is added to any of the processing units in the distributed processing system, and then the first server program is deleted from the distributed processing system, thereby replacing the server program. A program online replacement method characterized by performing the following.

4) The remote procedure call processing method described in 3) above, wherein the second server program is a newer version of the first server program than the first server program. .

5) In the remote procedure call processing method described in 1), the distributed system includes a plurality of processing units for acquiring information, a plurality of processing units for providing information, and a plurality of processing units for acquiring information. And at least one processing means interposed between the information processing means and the plurality of processing means for providing information are connected to each other via a transmission network, and the interposed processing means receives the request content of the processing means for obtaining the information. And at least one
Requesting information provision to the two processing means for providing information, the intervening processing means receiving the information provided by the processing means for providing at least one information, and requesting the processing means for obtaining the information A service providing system, which is a service providing system that integrates the received information based on contents and transmits the integrated information to a processing unit that acquires the information.

6) In the service providing system as described in 5) above, a new intervening processing unit different from the intervening processing unit is added, and the new intervening processing unit is
A new quality information is created by integrating the information based on the request content of the processing means for performing the information acquisition using the new information integration method, and the integrated new quality is processed by the processing means for performing the information acquisition. A service providing system for transmitting information.

[0259]

According to the present invention, in a remote procedure call processing system in which a procedure execution side of a three-tiered client / server model is multiplexed, another procedure execution request issued by the procedure execution side is transmitted to another procedure. The execution side can efficiently reduce the processing load, and can effectively control the storage period of the cache contents and the size of the cache memory.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of a distributed system using a remote procedure call processing method according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an overall configuration of a distributed system using a remote procedure call processing method according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram of a format of an RPC request message transmitted in a remote procedure call processing method according to an embodiment of the present invention.

FIG. 4 is a block diagram of a processing device configuring a distributed system using a remote procedure call processing method according to an embodiment of the present invention.

FIG. 5 illustrates a client RP according to an embodiment of the present invention.
It is a PAD diagram showing C request processing.

FIG. 6 is an RPC of a communication processing unit according to an embodiment of the present invention;
FIG. 9 is a PAD diagram illustrating an example of processing of a client processing unit.

FIG. 7 is a configuration diagram of an address table in an RPC processing unit according to an embodiment of the present invention.

FIG. 8 is a configuration diagram of a transmission information table in an RPC processing unit according to an embodiment of the present invention.

FIG. 9 is an RPC of a communication processing unit according to an embodiment of the present invention;
FIG. 9 is a PAD diagram illustrating an example of a process at the time of reception of a server processing unit.

FIG. 10 is a configuration diagram of a transmission / reception information table in an RPC processing unit according to an embodiment of the present invention.

FIG. 11 is a PAD diagram showing processing contents of a server in a processing device according to an embodiment of the present invention.

FIG. 12 is a diagram illustrating an RP of a communication processing unit according to an embodiment of the present invention;
PAD showing an example of processing at the time of transmission by C server processing means
FIG.

FIG. 13 is a configuration diagram of a nest procedure management table in the RPC processing unit according to an embodiment of the present invention.

FIG. 14 is a PAD diagram showing an example of a process performed when the nest server processing means of the communication processing unit receives the RPC request multiplex message according to the embodiment of the present invention.

FIG. 15 is a configuration diagram of an execution result cache table in the RPC processing unit according to an embodiment of the present invention.

FIG. 16 is a configuration diagram of an input / output correspondence table in the RPC processing unit according to an embodiment of the present invention.

FIG. 17 is a block diagram showing an overall configuration of a distributed system using a remote procedure call processing method according to another embodiment of the present invention.

FIG. 18 is a block diagram showing an overall configuration of a distributed system using a remote procedure call processing method according to another embodiment of the present invention.

FIG. 19 is an explanatory diagram of a format of an RPC request message transmitted in a remote procedure call processing method according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Communication medium 2, 3, 4, 5 ... Processing apparatus 20, 30, 40, 50 ... RPC processing part 21 ... Communication processing part 21A ... RPC client processing means 21B, 21C ... RPC server processing means 21D ... RPC nest server processing Means 22 Client 23 24 24 33 Server 24 53 Nest server 100 Address table 110 Transmission information table 120 Transmission / reception information table 130 Nest procedure management table 140 Execution result cache table 150 Input / output correspondence table

(72) Inventor Takashi Hashimoto 5030 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Software Development Division, Hitachi, Ltd.

Claims (5)

[Claims] In a remote procedure call processing method in a distributed system in which a plurality of processing means have a hierarchical structure of three or more layers, processing means on a procedure execution side are multiplexed, and these processing means are connected by a transmission network, The processing means having received the call request message detects a multiplex request message based on the contents of the user data portion included in the remote procedure call request message, selects one of the multiplex request messages, and selects the selected multiplex request message. Executing its own process using the message, returning the execution result to the transmission source processing means of the selected multiplex request message, and transmitting the processing result of the multiplex request message whose information obtained by duplicating the execution result was not selected. To the remote procedure call request message A remote procedure call processing method for managing cache information for a multiplexed remote procedure call request based on information on the number of processing means of a destination requested for a remote procedure call included in a remote procedure call. 2. The remote procedure call processing method according to claim 1, wherein the processing means for requesting the remote procedure call includes information on the own processing means, an event identifier indicating the order of generation of the request, and a lower order requesting the remote procedure call. Sending a first remote procedure call request message to the transmission network to which information of the number of destination processing units is added, wherein the destination processing unit is a multiplexed processing unit, and The event identifier and the destination of the first remote procedure call request message are included in a remote procedure call request message of a remote procedure call request for a lower-level processing means generated during its own processing started based on the remote procedure call request message. And the number of processing units Sending the second remote procedure call request message to the transmission network, and receiving the second remote procedure call request message, the further lower processing means comprises the processing device of the destination in the remote procedure call request message A remote procedure call processing method for managing the cache information for a multiplexed remote procedure call request based on a number. 3. The remote procedure call processing method according to claim 1, wherein said processing means for requesting a remote procedure call calls a plurality of processing means belonging to the same processing in response to one remote procedure call request. One of the plurality of processing means belonging to the process is arbitrarily selected by the request source, and the information of the own processing means and the event identifier indicating the order of occurrence of the request and the lower order destination requesting the remote procedure call are called. A first remote procedure call request message to which information on the number of processing means is added is sent to the transmission network. The called processing means (proxy processing means) executes its own processing and receives a request from the request source. The first processing unit calls the remaining processing means by copying the The respective processing means, which has duplicated the procedure call request message and transmitted it to the transmission network, have received the first remote procedure call request message, have their own processing units started based on the received first remote procedure call request message. The event identifier and the number of destination processing units of the first remote procedure call request message are added to a remote procedure call request message of a remote procedure call request for lower-level processing means generated during processing, and The second lower level processing means, which has transmitted the second remote procedure call request message to the transmission network, receives the second remote procedure call request message, and processes the destination in the remote procedure call request message. A remote procedure call processing method for managing the cache information for a multiplexed remote procedure call request based on the number of processing devices. 4. The remote procedure call processing method according to claim 2, wherein said processing means having received said first remote procedure call request message starts on the basis of said first remote procedure call request message. The second remote procedure call request message of the remote procedure call request generated during its own processing is further added with a nested event serial number indicating the order in which the requests generated during its own processing are generated and transmitted to the transmission network. A remote procedure call processing method. 5. The remote procedure call processing method according to claim 1, wherein detection processing of a multiplex request message belonging to the same processing having the same event identifier or the same processing as the same event identifier is performed. A remote procedure call process, wherein a period during which a process of detecting a multiplex request message belonging to the same process having a nested event serial number is performed is completed until the number of the multiplex request messages equal to the number of the destination processing devices has been fetched. method.