JPH10326217A - Remote file inputting and outputting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an efficient inputting and outputting method by finding a transfer unit according to the size of data requested to be inputted and outputted, adjusting the transfer unit according to the success rate of data transfer, and also adjusting the constitution of transmit and receive date storage areas according to the distribution of transfer units of remote file input/output requests. SOLUTION: Each time a request to input or output a remote file is made, a transfer unit is determined according to the size of the data requested to be inputted or outputted and adjusted according to the success rate of data transfer, and the constitution of transmit and receive data storage areas is adjusted according to the distribution of remote file input/output requests that a client computer is processing. In this system, a transmit data storage area 131 and a receive data storage area 132 are controlled on a client 100 according to a transmit and receive data storage area control table 180. On a server 200, on the other hand, a transmit data storage area 231 and a receive data storage area 232 are controlled with a transmit and receive data storage area control table 280.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for inputting and outputting a remote file between computer systems.

[0002]

2. Description of the Related Art Distributed computing environments in which computer systems of various scales such as personal computers, workstations, and mainframes are connected by a network have been constructed. In such a distributed computing environment, various information is usually shared by a distributed file system. In particular, the specification of a distributed file system developed by Sun Microsystems (USA)
FS & NIS ”ASCII Publishing Bureau, pp. 183-21
8 (1992) (Original: Managing NFS and NIS, Original author: Hal Stern, Original publisher: O'Reilly & Associates, In
c.) is used for distributed file systems as an industry standard.

In this distributed file system, input / output requests from a client computer to a server computer are read / written in units called buffer sizes. This buffer size is independent of the physical packet transfer unit of the network and the disk input / output unit of the computer system. Version 2, released in 1985, had a buffer size limit of 8 kilobytes. With the availability of highly reliable networks and the transfer of large data of several megabytes, such as moving image data, this upper limit was removed in version 3 released in 1993. It is now possible to set an arbitrary value as the buffer size depending on the individual implementation.

In version 2, the buffer size is
Based on the performance of the network, client computer, and server computer, it is set when the file system is mounted by the computer administrator, not at the time when input / output processing is performed, and the buffer size once set is used when the file system is mounted. During that time it was constant. In version 3, the computer administrator sets the maximum value of the buffer size and a value considered preferable for the file system, and can know the values when the client performs input / output. However, these values are stored as static information of the file system and are not dynamically changed.

[0005]

In a file system, files of various sizes, such as a large file having a size of several megabytes such as image data and a relatively small file having a size of several kilobytes such as a program, are included. Mix. Therefore, if the buffer size is determined when mounting the file system, or if the preferred buffer size of the file system is statically determined, if the buffer size is set to a large value, it will Is too large, and if the buffer size is set to be small, it is too small for a large-sized input / output request.

For example, if a remote input / output request for small data occurs when the buffer size is set to be large, the processing of the input / output request is performed until the input / output request for data of the buffer size is accumulated, or This wait must be delayed until it times out. Also, for example, when a remote I / O request for large data occurs when the buffer size is set to be small, a number of small-sized I / O requests must be issued to process the I / O request. .

An object of the present invention is to provide an efficient remote file input / output method even when input / output of large data and small data is mixed.

[0008]

In order to achieve the above object, according to the remote file input / output method of the present invention, when a client computer issues a new remote file input / output request, the remote file input / output request is issued. If the size of the data to be transmitted is larger than a certain value, each remote file input request (remote file output request) can be written to the reception data storage area (transmission data storage area) at a time. Is hereinafter referred to as an input buffer size (output buffer size)) based on the size of the data requested to be input / output by the remote file input / output request.

The transmission / reception data storage area includes a plurality of types of lists of continuous areas (message buffers) having a certain size. The plurality of types of message buffer lists include a list of message buffers (default message buffers) of a size determined based on the memory management characteristics of the computer, and a multiple of the size of the default message buffer. It contains a list of message buffers that are large enough that they are less than or equal to the maximum possible data transfer size of the network.

The input / output buffer size of the remote file input / output request is set to the default message buffer size when the data size of the input / output request is smaller than a predetermined value, and If the size is larger than a predetermined value, it is set to the maximum value among the message buffer sizes that are smaller than the data size required for input / output. When processing each remote file input / output request, a list of message buffers having the same size as the input / output buffer size of the remote file input / output request is used.

The client computer sets the input buffer size (output buffer size) to a smaller message buffer size when reception (transmission) of the data of the input buffer size (output buffer size) fails more than a certain standard. If the reception (transmission) of the data of the input buffer size (output buffer size) succeeds by a certain level or more, the input buffer size (output buffer size) is set to a larger message buffer size.

If the usage rate of a certain message buffer size list is lower than a certain reference and the usage rate of another message buffer size list is higher than a certain reference, a message buffer list of an appropriate size is newly added. create.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a remote file input / output method according to the present invention will be described in detail with reference to the drawings.

[1] Outline of Configuration FIG. 1 shows an example of the configuration of a client server system that implements a remote file input / output method according to the present invention. 100 denotes a client computer (hereinafter, referred to as a client for simplicity), 200 denotes a server computer (hereinafter, referred to as a server for simplicity), 300 denotes a network, and 310 denotes a disk. The client and server are connected by a network.

On the client 100, under the control of the OS 110, a user program 120, a client remote file input / output processing program 130, an input / output buffer setting program 140, an input / output buffer update program 150, and a transmission / reception data storage area adjustment program 160 operate. The transmission data storage area 131 and the reception data storage area 132 are managed by a transmission / reception data storage area management table 180.

On the server 200, under the control of the OS 210, the remote file input processing program 23
0, the transmission / reception data storage area adjustment program 260 is running, and the transmission data storage area 231 and the reception data storage area 232 are managed by the transmission / reception data storage area management table 280.

When the client 100 issues a remote file output (write) request to the server 200, the output data is written to the transmission data storage area 132 and moves to the reception data storage area 231 of the server 200 via the network 300. Client 100 is server 200
When a remote file input (read) request is issued to the server 200, the input data is written to the transmission data storage area 232 of the server 200, and the data moves to the reception data storage area 131 via the network 300.

[2] Embodiment of Remote File Output Method Next, the flow of the remote file output method will be described with reference to a specific example. FIG. 2 shows a time chart of a main part of the remote file output method of the present invention in an example in which a user program requests remote file output on the client 100. Time chart is client remote file I / O processing program 1
30 (output) and the operation of the server remote file input / output processing program 230 (input).

(1) Remote File Output Request 400 When the user program 120 makes a remote file output request 400 in the client 100, the client remote file input / output processing program 130 is executed.

FIG. 3 shows a processing flow of the client remote file input / output processing program 130 (output).
The input / output buffer setting program 140 is executed (step 500), and the output buffer size of the remote file output request 400 is set. FIG. 4 shows the flow of processing of the input / output buffer setting program 140.

It is checked whether or not the output data size is smaller than a certain reference (step 600). If it is smaller, the output buffer size is set to the default message buffer size (step 610). If the output data size is equal to or larger than a certain standard, the transmission / reception data storage area management table 18
0, if there is a message buffer larger than the output data size, the minimum message buffer size is set as the output buffer size in the input / output buffer management table 170 as the output buffer size otherwise (step 620). The number of remote file output requests that use the message buffer list of the output buffer size in the transmission / reception data storage area management table 180 is increased by one (step 621).

(2) Data transmission 401 Client remote file input / output processing program 1
30 checks whether or not unoutput data exists (step 501). If no unoutput data exists, the client remote file input / output processing program 130 ends. If there is unoutput data, the output buffer size of the remote file output request 400 is referred to (step 502), and the data of the output buffer size is written to the message buffer of the output buffer size (step 503) and written. The data is transmitted to the remote file output request destination server 200 (step 504), and the message buffer usage rate and the message buffer list usage rate are updated for the message buffer list of the output buffer size in the transmission / reception data storage area management table 180 (step 504). Step 505). Then, the transmission / reception data storage area adjustment program 160 is executed (step 506), and the process waits until an output buffer transfer success / failure notification is received from the server 200 (step 507).

FIG. 5 is a transmission / reception data storage area management table 180.
This is an example. FIG. 5 shows that 80% of the remote file output requests of the client 100 use a message buffer of 60 kilobytes, and 60% in one data transmission.
This shows that the kilobyte message buffer uses only 8 kilobytes on average.

FIG. 6 shows the flow of processing of the transmission / reception data storage area adjustment program 160. It is checked whether there is a message buffer list whose usage rate is higher than a certain reference (step 700). If there is, a new message buffer list is created based on the message buffer usage rate of the message buffer list (step 71).
0). It is checked whether there is a message buffer list in which the usage rate is smaller than a certain reference and there is no remote file output request being used (step 701). If there is, the message buffer list is deleted (step 720).

(3) Data reception 402, data transfer success / failure notification transmission 403 Upon receiving the write data, the server 200 executes the server remote file input / output processing program 230.

FIG. 7 shows a server remote file input / output processing program (input). Referring to the transmission / reception data storage area management table 280, it is checked whether there is a message buffer larger than the size of the received data (step 80).
0). If not, the transfer failure is notified to the client 100 (step 820), and the server remote file input / output processing program 230 ends. If there is a message buffer larger than the size of the received data, the data is read out to the smallest one of the message buffers (step 810), and the message buffer usage rate and the message buffer list usage rate in the transmission / reception data storage area management table 280 are checked. Update (step 811). Then, the transmission / reception data storage area adjustment program 160 is executed (step 812), and the transfer success is notified to the client 100 (step 813).

(5) Data transfer success / failure notification reception 40
4 When the client 100 receives the data transfer success / failure notification, the transfer success rate is updated for the remote file output request 400 in the input / output buffer management table 170 (step 508), and the input / output buffer update program 150 is executed (step 509). ). If all of the transmitted data of the output buffer size has not been received, the transfer is considered to have failed. After executing the input / output buffer update program, the process returns to step 501.

FIG. 8 shows an example of the input / output buffer management table 170. FIG. 8 shows that the input / output buffer size of the remote file input / output request 400 is 4 kilobytes and the transfer success rate is 95%.

FIG. 9 shows an input / output buffer update program 15.
0 shows the flow of processing. The input / output buffer update program 150 checks whether the transfer success rate of the input / output buffer is smaller than a certain standard (step 900). If the size is smaller, the I / O buffer size is set to a smaller message buffer size than the current one by referring to the I / O data storage area management table 180 (step 901). It is checked whether the success rate of the transfer of the input / output buffer is higher than a certain reference (step 902). If so, the input / output buffer size is set to the size of the message buffer larger than the current one by referring to the input / output data storage area management table 180 (step 903).

[3] Embodiment of Remote File Input Method Next, the flow of the remote file input method will be described with reference to a specific example. FIG. 10 is a time chart of a main part of the remote file input method of the present invention in the case where the client 100 issues a remote file input request. The time chart shows the operation of the client remote file input / output processing program 130 (input) and the server remote file input processing program 230 (output).

(1) Remote File Input Request 1000 When the user program 120 of the client 100 issues a remote file input request 1000, the client remote file input / output processing program 130 is executed.

FIG. 11 shows the flow of processing of the client remote file input / output processing program 130 (input). The input / output buffer arbitration program 140 is executed (step 1100), and the remote file input request 1000 is executed.
Set the input buffer size of It is checked whether or not uninput data exists (step 1101). If there is no uninput data, the client remote file input / output program 130 is terminated. If there is uninput data, the input buffer size of the remote file input request 1000 is referred to in the input / output buffer management table 170 (step 1102), and the input request / input buffer size is transmitted to the remote file input request destination server 200. The data is transmitted (step 1103).

(3) Remote file input request / input unit reception 1002 When the server remote file input / output processing program 230 receives the remote file input request / input buffer size transmitted from the client 100, the server remote file input / output processing program 230 Execute 230.

FIG. 12 shows the flow of processing of the server remote file input / output processing program 230. Referring to the transmission / reception data storage area management table 280, the client 100 that has issued the remote file input request uses the largest message buffer that is smaller than the received input buffer size.
(Step 1200). The message buffer usage rate and the message buffer list usage rate in the transmission / reception data storage area management table 280 are updated (step 1).
201), transmission / reception data storage area adjustment program 260
Is executed (step 1202).

(5) Receipt of data and data transfer success / failure notification 1004 When the client 100 receives the data and data transfer success / failure notification, the received data is read into the message buffer of the input buffer size (step 110).
5) For the message buffer list of the input buffer size of the remote file input request 1000 in the transmission / reception data storage area management table 180, the message buffer usage rate and the message buffer list usage rate are updated (step 1105), and the transmission / reception data storage area adjustment is performed. The program 160 is executed (Step 1106). Then, the transfer success rate of the remote file input request 1000 in the input / output buffer management table 170 is updated (step 1107),
The input / output buffer update program 150 is executed (Step 1108). If the size of the received data is smaller than the input buffer size, the transfer is considered to have failed. After executing the input / output buffer update program 150, the process returns to step 1102.

[0036]

According to the present invention, each time a remote file input / output request occurs, the transfer unit is determined based on the size of the data requested to be input / output, and the transfer unit is adjusted based on the data transfer success rate. By adjusting the configuration of the transmission / reception data storage area in accordance with the distribution of the transfer unit of the remote file input / output request being processed by the client computer, efficient remote file input / output is possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a client server system according to an embodiment of the present invention.

FIG. 2 is a time chart of a remote file output example.

FIG. 3 is a flowchart of a client remote file input / output processing program (output).

FIG. 4 is a flowchart of an input / output buffer setting program.

FIG. 5 is an explanatory diagram showing the structure of a transmission / reception data storage area management table.

FIG. 6 is a flowchart of a transmission / reception data storage area adjustment program.

FIG. 7 is a flowchart of a server remote file input / output processing program (input).

FIG. 8 is an explanatory diagram showing the structure of an input / output buffer management table.

FIG. 9 is a flowchart of an input / output buffer update program.

FIG. 10 is a time chart of a remote file input example.

FIG. 11 is a flowchart of a client remote file input / output processing program (input).

FIG. 12 is a flowchart of a server remote file input / output processing program (output).

[Description of References] 100: Client computer, 110: OS, 120:
User program, 130: client remote file input / output processing program, 131: transmission data storage area, 132: reception data storage area, 140: input / output buffer setting program, 150: input / output buffer update program, 160: transmission / reception data storage area adjustment Program, 170: Input / output buffer management table, 180: Transmission / reception data storage area management table, 200: Server computer, 210 ...
OS, 230: remote file input processing program,
231, a transmission data storage area, 232, a reception data storage area, 260, a transmission / reception data storage area adjustment program,
280: transmission / reception data storage area management table, 300: network, 310: disk.

Claims (7)

[Claims] In a client-server system comprising a client computer for requesting remote file input / output and a server computer for processing the request, the client computer receives a remote file input of data of a predetermined size or more (remote file input). File output)
When a new request is made, the input buffer size (output buffer size), which is called the input buffer size (output buffer size), is set at once in the reception data storage area (transmission data storage area) set for each remote file input request (remote file output request). A remote file input / output method, wherein the size of writable data is set based on the size of data requested by each remote file input request (remote file output request). 2. The remote file input / output method according to claim 1, wherein the transmission / reception data storage area has a plurality of types of lists of continuous areas having a certain size, which are called message buffers. 3. The computer has a list of message buffers, called a default message buffer, of a size determined based on the memory management characteristics of the computer,
2. The remote file input device according to claim 1, wherein there is a list of message buffers having a size that is a multiple of the default message buffer size and that satisfies a condition that it is equal to or less than a maximum transfer buffer size of an available network. output method. 4. The input / output buffer size of each remote file input / output request is set to a default message buffer size when the data size requested for input / output is smaller than a predetermined value. If the data size to be input is larger than the predetermined value, if there is a message buffer larger than the data size required for input / output, the message buffer size larger than the data size required for input / output 2. The remote file input / output method according to claim 1, wherein if there is no message buffer size, the maximum message buffer size is set. 5. The method according to claim 1, wherein, when processing each remote file input / output request, a list of message buffers having a size equal to the input / output buffer size of the remote file input / output request is used. Remote file I / O method. 6. When the client computer fails to receive (transmit) data of the input buffer size (output buffer size) at a certain level or more, the client computer reduces the input buffer size (output buffer size) according to a certain level. 2. The remote file input according to claim 1, further comprising the step of increasing the input buffer size (output buffer size) according to a criterion when the reception (transmission) of the data of the input buffer size (output buffer size) is more than a criterion. output method. 7. If the usage rate of a certain message buffer size list is lower than a certain reference and the usage rate of another message buffer size list is higher than a certain reference, a message buffer list of an appropriate size is set. 2. The remote file input / output method according to claim 1, wherein the remote file input / output method is newly created.