JP2000322365A - Server computer reception restriction method - Google Patents

Abstract

(57) [Summary] In a client-server system, when a processing request from a client is restricted on the server side, the reception is restricted directly based on the load state of the server. A load state value is a numerical value indicating a server load calculated by a load state value calculation unit and collected by a load detection unit. The load determination table 24 stores a load determination value of each function corresponding to the function-specific processing program 28. When receiving a processing request from the client 1, the server accepting unit 27 compares the requested load determination value of the function-specific processing program 28 with the load state value 23 at that time with reference to the load determination table 24, and It is determined whether the processing request can be accepted according to the comparison result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a client-server system having a client computer and a server computer, and more particularly to a method for restricting a processing request of a client computer on a server computer side.

[0002]

2. Description of the Related Art At present, client-server systems are widely used. In this client-server system, the load state of the server computer is generally determined by the number of transactions connected to the client or the number of processing processes started on the server in response to a processing request from the client. For example, JP-A-6-314
According to Japanese Patent No. 263, the number of processing processes on the server side is controlled according to the load state of the server.

[0003]

According to the above-mentioned prior art, the processing request from the client is restricted only by the number of processing processes, so that the load imposed by the processing request from the client is light and the processing capacity of the server is sufficient. Even in a certain state, when the upper limit of the number of processing processes is reached, acceptance of a processing request from a new client is refused. Conversely, even if the load on the server is heavy and the processing capacity of the server has no margin, if the number of processing processes does not reach the upper limit, a processing request from a new client will be accepted, and the response performance to the client will be degraded. .

An object of the present invention is to solve the problems of the prior art by directly limiting the processing requests from clients based on the load state of a server.

[0005]

According to the present invention, a first index that changes in accordance with the load state of a server computer is stored in a storage device, updated by the server computer, and processed by the server computer from a client computer. The method is characterized in that a second index corresponding to the function program requested in response to the request is compared with the first index, and a reception restriction method of the server computer that determines whether to accept the processing request based on the comparison result.

[0006]

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

FIG. 1 is a configuration diagram of a client server system of the present embodiment. The system includes a server 2 and a plurality of clients 1 connected to the server 2 via a network 3. The client 1 is a computer such as a personal computer.
And the input device 12 are connected. The display device 11 displays buttons corresponding to various functions and information such as search results acquired from the server 2. The input device 12 is a device such as a keyboard and a mouse for instructing function buttons and inputting data such as search conditions. In the memory of the client 1, an application program 13, a reception request unit 14 as a common module, a login request unit 15
1, programs such as the list search request unit 15-2 are stored and executed by the processing device of the client 1. The reception request unit 14 is called from the application program 13 via the request unit 15 and
7 is called and a reception request is made. Login request unit 15-
1. The requesting unit 15 such as the list search requesting unit 15-2 is called from the application program 13, inquires of the server 2 via the reception requesting unit 14 whether or not reception is possible. The function-specific processing program is called to receive the service of the corresponding server function.

The server 2 is a computer such as a personal computer, a workstation, or a server dedicated machine that functions as a server. A disk storage device 21 is connected to the processing device, and a database 22 is stored on the disk storage device 21. In the memory of the server 2, data of the load state value 23 and a load determination table 24 are stored. Load state value 2
3 is an index value indicating the magnitude of the load applied to the server 2. The load determination table 24 stores a processing program for each function of the server 2 and an index value for load determination corresponding to the function. In the memory of the server 2, processing programs for respective functions such as a load detection unit 25, a load state value calculation unit 26, a server reception unit 27, a login processing unit 28-1, and a list search unit 28-2 are stored. Performed by the device. The load detecting unit 25 periodically measures the use status of the resources of the server 2 and stores the measured status in the memory. The load state value calculation unit 26 calculates the load state value 23 from the measured numerical value of the use state of the resource. Server reception unit 27
Determines whether the reception is OK or rejects the reception by comparing the load state value 23 with the index value on the load determination table 24 corresponding to the requested function when there is a reception request from the reception request unit 14. I do. The login processing unit 28-1, the list search unit 28-2, and the like are function-specific processing programs, and are called and executed by the client 1. List search unit 28-2, DB (database) update unit 28-3
Such a program accesses the database 22 on the disk storage device 21.

FIG. 2 shows the function buttons 16 on the display device 11.
FIG. 7 is a diagram illustrating a state in which each functional module is called in response to the above. When a function button displayed on the display device 11 is instructed via the input device 12, the application program 13 is notified via a graphical user interface (not shown). When the application program 13 calls the corresponding request unit 15, the corresponding request unit 15 first calls the reception request unit 14 with the function number. The reception requesting unit 14 transmits the server reception unit 2 by RPC (Remote Procedure Call).
Call 7 The server receiving unit 27 determines whether or not the function module can be received, and returns the result to the requesting unit 15 via the reception requesting unit 14. If the reception is OK, the request unit 15 calls the corresponding function-specific processing program of the server 2 and requests the service of the function.
The function-specific processing program generates a new process, performs the process, and returns a processing result to the requesting unit 15 of the caller. The requester 15 of the caller further returns a processing result to the application program 13 of the caller. The application program 13 performs processing such as displaying the processing result on the display device 11.

The load state value 23 is a numerical value indicating the load state of the server 2 and is calculated from the average resource utilization of the server 2. The average resource utilization of the server 2 is calculated by the following equation. Average resource utilization = weight 1 x C
PU usage rate + weight 2 x memory usage rate + weight 3 x
Disk usage rate + weight 4 x network usage rate + weight 5 x number of simultaneous database accesses + ... CPU, memory, disk, network, etc. are hardware resources, and the usage rate and usage rate are from 0 to 1.
It is a numerical value in the range up to 00. The number of simultaneous database accesses is a numerical value indicating the usage status of software resources, and is assumed to be converted to a numerical value with its upper limit being 100. The weights 1, 2, 3,... Are numbers in the range from 0 to 1, and the weights 1, 2, 3,.
・ ・ The sum of all weights is 1, etc. The load state value 23 is a numerical value converted so that the practical upper limit of the average resource utilization rate is normalized to, for example, 100. For example, the practical upper limit of the average resource utilization is 80
%, The average resource utilization rate is 0, 40, 80, 10
The primary conversion of 0 is the load state value 0, 50, 100,
125.

Generally, the average response time to the client 1 increases as the average resource utilization rate increases.
That is, the average resource utilization can be regarded as a monotonically increasing function related to the average response time. Therefore, the average resource utilization rate corresponding to the upper limit of the average response time beyond which it is unacceptable can be regarded as the practical upper limit.

A value exceeding the range of the load state value calculated from the average resource utilization rate, such as "999", is set as the load state value 23 indicating "stopping" for stopping the service of the server 2.

FIG. 3 is a diagram showing the data structure of the load determination table 24. The function number 31 is a number assigned corresponding to each function-specific processing program such as a function, that is, a login processing unit 28-1 and a list search unit 28-2. The load determination value 32 is an index value for load determination corresponding to the function. Generally, the load determination value 32 of the function to be subjected to the reception restriction based on the load state of the server 2 is a load determination value =
It is given by normalization constant × priority coefficient / load coefficient. The priority coefficient is a weight indicating the priority of the function, and the larger the coefficient, the higher the priority. The load coefficient is a number indicating the degree to which the execution of the function program increases the average resource utilization rate, and the larger the coefficient, the larger the load increase. The normalization constant is the priority coefficient ÷
The load judgment value of the function with the maximum load coefficient is set to 100, for example.
This is a constant introduced to normalize to, and is common to all functions that restrict acceptance. The load determination values 32 of all the functions for which the reception is restricted are the load state values 23
Must not exceed the practical upper limit of. Under this condition, the load judgment value 32 of any function subject to the reception restriction is:
The load state value 23 has a correlation that is larger, equal, or smaller than the load state value 23 calculated at the time of receiving the request. Note that the load coefficient may always be 1, and the load determination value of each function may be determined only by the priority coefficient. Conversely, the priority coefficient may be set to 1, and the load determination value of each function may be determined only by the load coefficient. Further, the load determination value may be fixed for all the functions for restricting the reception regardless of the priority coefficient or the load increment. In this case, a constant value that does not exceed the practical upper limit of the load state value 23 is set as the load determination value.

Regarding the function that is unconditionally accepted during the service of the server 2 irrespective of the load state of the server 2, the load judgment value 32 is always set to a numerical value larger than the load state value 23, such as "999". , Or 0, which is a numerical value identified and determined by the program of the server reception unit 27.

The load detecting unit 25 periodically measures the utilization rate and the numerical value indicating the utilization state of each resource for which the load state value is to be calculated, and stores a plurality of latest measured values for each resource in the memory. save.

FIG. 4 is a flowchart showing the flow of the processing of the load state value calculating section 26. Load state value calculator 26
Initializes the contents of a counter for counting the number of times the load state value 23 has been set to 0 after performing necessary initialization processing such as securing a memory (step 41). When the service of the server 2 is stopped, a termination processing program (not shown) is started via the input device 12, and the termination processing program is executed.
3 is set to a numerical value indicating “stop” such as “999”. The load state value calculation unit 26 refers to the load state value 23 in step 42 and determines whether or not an end instruction is indicated. If it is a termination instruction (YES in step 42), the processing of the load state value calculation unit 26 is terminated. If it is not an end instruction (NO in step 42), the latest numerical value indicating the utilization rate or the utilization state of the resource is obtained from the load detection unit 25 (step 43), and the utilization rate or utilization obtained by averaging the measured values of the resources for a plurality of times is obtained. The average resource utilization is calculated by applying the above average resource utilization formula to the numerical value (step 4).
4) The obtained average resource utilization rate is normalized and converted into a load state value (step 45). Next, the calculated numerical value is set as the load state value 23 (step 46). Next, 1 is added to the value of the set number counter of the load state value 23 (step 47). Next, the remainder is obtained by dividing the set number of the counter by the log interval (step 48). The log interval is an integer indicating how many times the counter is set to acquire one log. If the remainder is not 0 (step 49
NO), go to step 51; If the remainder is 0 (step 49YES), the time is displayed on a log file (not shown).
The average utilization rate, average utilization numerical value, and load state value of each resource are output (step 50). By using the obtained load state statistics log, the above formula of the average resource utilization rate can be tuned. Next, the process waits for a predetermined time (step 51), and thereafter returns to step 42 and repeats the above processing again.

FIG. 5 is a flowchart showing the flow of the process of the server receiving unit 27. The server receiving unit 27 receives the reception request from the client 1 (step 6
1) The load determination value 32 corresponding to the function number added to the reception request is read with reference to the load determination table 24 (step 62). Next, the latest load state value 23 is read (step 63). If the load state value 23 is a numerical value indicating a stop, such as "999" (step 64YE
S), the process returns to the client 1 with the stopped error code (step 65). When the server 2 is not stopped and the function number corresponding to the load determination table 24 cannot be found (NO in step 66), the process returns with an error code without a function number (step 6).
7). When there is a corresponding function number in the load determination table 24 (step 66 YES), the read load determination value 3
2 is compared with the load state value 23 (step 68). If the load determination value ≧ the load state value, the process returns with a code of acceptance OK (step 69). If the load determination value <the load status value, the time, the requested function number, and the load status value are output to a reception rejection log file (not shown) (step 70), and the process returns with a reception rejection code (step 71). . The degree of service to the client 1 can be known from the obtained rejection log. Also, by matching the contents of the load state statistical log, the correlation between the load state value and the load determination value of each function can be analyzed. Regarding the function that is unconditionally accepted, the load determination value can always exceed the load state value, so that the acceptance OK can be unconditionally returned. Alternatively, the load determination value of the function is set to a numerical value such as 0, and a determination step of determining whether or not the function is an unconditional reception function is provided between Step 64 and Step 66. It may be a return.

FIG. 6 shows the application program 13
4 is a flowchart showing a flow of processing of a request unit 15. The application program 13 calls one of the request units 15, for example, the list search request unit 15-2 according to the instruction from the input device 12 (step 81). As a result, if the return code is OK (step 8)
2YES), the search result stored in the contact area on the memory is displayed on the display device 11 (step 83). If the return code is rejected (NO in step 82), a message indicating the server overload state is displayed on the display device 11 (step 84).

The list search request unit 15-2 receives the call from the application program 13, sets the function number as an argument, and calls the reception request unit 14 (step 9).
1). As a result, the reception request unit 14 calls the server reception unit 27, the server reception unit 27 is executed, and the execution result returns to the list search request unit 15-2 via the reception request unit 14. As a result, if the return code is accepted (YES in step 92), the list search unit 28-2 is called using the search condition as an argument (step 93). As a result, the obtained search results are stored in the application program 1
3 (step 94), and returns to the application program 13 called with the return code as acceptance OK (step 95). If the return code is rejection (NO at step 92), the rejection is set as the return code, and the process returns to the application program 13 (step 96).

If the server 2 is stopped or returns an error due to no function number, a corresponding return code is returned when returning from the call in step 91. Therefore, the list search request unit 15-2 accompanies the return code. To return to the application program 13. The other request units 15 have the same processing procedure as described above.

[0021]

As described above, according to the present invention, the acceptability is determined directly according to the function requested by the client based on the load state of the server computer.
It is possible to overcome the problem of the reception restriction method based on the mere number of processing processes. In particular, since strict control is performed to ensure the response performance to the client, a stable response time is guaranteed. If the above-mentioned load determination value is set depending on the priority of the function, the control method is such that a function with a higher priority is more difficult to be rejected. If the load determination value is set depending on the load increment applied to the server by the function, the control method is such that the larger the load determination value is, the more difficult it is to reject the function. Further, when the load determination value is set near the allowable upper limit, the processing request is hardly rejected, and the response performance can be secured.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a client server system according to an embodiment.

FIG. 2 is a diagram illustrating a state where each functional module is called;

FIG. 3 is a diagram illustrating a data configuration of a load determination table 24 according to the embodiment.

FIG. 4 is a flowchart illustrating a processing flow of a load state value calculation unit 26 according to the embodiment.

FIG. 5 is a flowchart illustrating a process flow of a server reception unit 27 according to the embodiment.

FIG. 6 is a flowchart illustrating a processing flow of an application program 13 and a request unit 15 according to the embodiment.

[Explanation of symbols]

1: client, 2: server, 23: load status value, 2
4: load determination table, 26: load state value calculation unit, 2
7: server reception unit, 31: function number, 32: load determination value

Continued on the front page (71) Applicant 391002409 Hitachi System and Service Co., Ltd. 3-2-1-16 Omorikita, Ota-ku, Tokyo (72) Inventor Akira Tanikawa 8-4-17-1 Ginza, Chuo-ku, Tokyo Recruit GINZA8 (72) Inventor Atsushi Tanaga 8-4-17 Ginza, Chuo-ku, Tokyo Recruit GINZA8 (72) Inventor Minoru Matsushima 8-17, Ginza, Chuo-ku, Tokyo Recruit GINZA8 ( 72) Inventor Ikumasa Kogami 1-16-5 Dogenzaka, Shibuya-ku, Tokyo Inside Hitachi Information Systems Co., Ltd. Inventor Makoto Yoshida F-term (reference) 5B045 FF14 GG04 5B089 GA11 GA21 JB10 KA06 KB10 KB13 KC48 KC52 LB04 LB04 LB04 MA01 MA07 3-2-1-16 Omorikita, Ota-ku, Tokyo

Claims (1)

[Claims] 1. A reception restriction method for a client-server system, comprising: a client computer that makes a processing request; and a server computer that receives and processes the processing request and returns a processing result to the client computer. A first index that changes in accordance with the second index corresponding to a function program requested by the server computer in response to a processing request from the client computer; A reception restriction method for a server computer, comprising: comparing a first index with a first index; and determining whether to accept a processing request according to a result of the comparison.