JPH02196359A - Data processing system - Google Patents

Abstract

PURPOSE:To improve the overall throughput of a program having a high priority rank by using an input/output schedule control means to set an input/output schedule which decide the input/output process priority based on the priority of tasks which produce the input/output requests. CONSTITUTION:An input/output schedule control means 5 sets an input/output schedule to decide the input/output process priority based on the priority of tasks which produces the input/output requests. For this purpose, the means 5 decides the processing order of input/output requests based on the priority of a task control table 6 to the input/output request of each program. The table 6 stores the task priority at generation of tasks. When each input/output request is produced and accepted, the priority of input/output request processes is decided based on the task priority of the table 6. In such a way, the input/ output schedule process is carried out. Thus it is possible to improve the overall throughput of a program having a high priority rank.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a data processing system capable of scheduling the processing order of input/output requests, and in particular to a data processing system capable of accepting input/output requests and creating a queue for each input/output request. The present invention relates to a data processing system having an input/output control mechanism that performs an input/output schedule and processes each input/output request according to the order of the input/output schedule.

[Conventional technology]

A data processing system includes a control program for managing and controlling input/output devices in a control program for controlling the system. The control program for this input/output processing is also called an input/output supervisor, and is responsible for accepting input/output requests.

It handles all processes related to input/output processing, such as execution of input/output operations, processing upon completion of input/output, and handling of input/output errors. In this way, the input/output supervisor has a request schedule processing function that accepts input/output requests from processing programs, etc., creates a queue for each input/output request, and schedules the input/output requests. , determine the input/output device and channel path, and select Star 1-I.
It has an input/output processing function that executes the O instruction, a function that performs completion processing using an input/output operation completion interrupt, and an error processing function that performs input/output error analysis processing 2 recovery processing. The functions of these input/output supervisors are e.g.
Toyotaka Tobita, Keigaku Publishing, published May 15, 1987, Introduction to Information Processing Series "Operating System" 15
The outline is explained on pages 2 to 157. The priority order of processing of input/output requests in such an input/output supervisor is determined, for example, as follows.

The request scheduler that receives a request from the supervisor interrupt program checks whether the environment for the input/output request is ready, and if all the control blocks that process the input/output request are available, the control block The actual page containing the data transfer area, etc.
Fix it to prevent it from happening. Then, the input/output request is sent to the input/output device as RQ E (request queue
e element). Registered queue elements are taken out and processed in order from the head of the queue as input/output devices and channels become available. RQEs registered as queue elements are normally retrieved in the order of the first registered RQE, first in, first out FIF○: f
j, rst j, n fr], st out) method.

In addition, for example, Japanese Patent Application Laid-Open No. 61-28291 proposes a method for speeding up processing of programs with high priority by setting priorities in a table for registering input/output requests.
There is a technique described in Publication No. 8. This is a technology related to a disk control method that speeds up the processing of high-priority programs by setting priorities in a table for registering input/output requests for disk files.

[Problem to be solved by the invention]

By the way, in the above-described control method, each input/output request is processed in the order in which it was registered first, using a FIFO method. Therefore, even if a processing program (job) has a high priority, if this processing program has a large number of input/output processes, the input/output requests will be processed in the order in which the input/output requests are registered. Therefore, even if the data processing part is processed at high speed, the throughput of the entire program is not improved due to the low throughput of input/output request processing.

Therefore, it is desirable to determine the processing priority of input/output requests based on, for example, the priority of a program (job) given from the outside, without changing the existing program.

On the other hand, as in the disk control method described in Japanese Patent Application Laid-Open No. 61-282918, priority is given to input/output processing by setting priorities in channel controller 1 to roll block (CCB). There is a method of performing processing early, but since this is for input/output processing requests for disk files, there is a problem in that the user's program must be changed in order to perform priority scheduling.

The present invention has been made to solve the above problems.

An object of the present invention is to provide a data processing system that can schedule the processing order of input/output requests without changing the user's program.

Another object of the present invention is to provide a data processing system that can perform an input/output schedule that determines the processing priority of input/output requests based on the program priority already set in the user's processing program. .

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Means to solve the problem]

In order to achieve the above object, the present invention performs an input/output schedule that receives each input/output request, creates a queue for each input/output request, and processes each input/output request according to the order of the input/output schedule. The data processing system has an input/output control mechanism that performs a scheduling process that determines the priority of input/output processing according to the task priority of a task that issues an input/output request.

In addition, the input/output schedule control means here performs a schedule process that determines the order of input/output processing based on the order in which input/output requests are accepted, or issues input/output requests, depending on the initial settings at the time of system generation. Select whether to perform schedule processing that determines the priority of input/output processing according to the task priority of the task. The input/output schedule is changed by the input/output schedule control means by changing the priority of user tasks using an external command.
Change the priority of input/output processing.

[Effect]

According to the above means, the data processing system is provided with an input/output schedule control means for performing an input/output schedule that determines the priority of input/output processing according to the task priority of the task issuing the input/output request. The data processing system performs an input/output schedule that accepts each input/output request and creates a queue for each input/output request;
It has an input/output control mechanism that processes each input/output request according to the order of the input/output schedule.

The input/output schedule control means here performs a human output schedule that determines the priority of input/output processing according to the task priority of the task that issues the input/output request. The processing order of input/output requests is determined based on the priority of the control table. The task priority is stored in the task control table when a task is created, and when each input/output request occurs and is accepted, the priority of input/output request processing is determined based on the task priority in the task control table. Ranking is determined. In this way, human output is scheduled, so high-priority programs can be given high priority in processing input/output requests, improving the overall throughput of high-priority programs. can do.

〔Example〕

Hereinafter, one embodiment of the present invention will be specifically described using the drawings.

FIG. 1 is a block diagram showing the system configuration of main parts of a data processing system according to an embodiment of the present invention. In FIG. 1, 1 is a central processing unit, and 2 is an input/output device.

A plurality of input/output devices 2 are connected to the central processing unit 1 via a channel device (not shown) to constitute one data processing system. The central processing unit 1 is equipped with a control mechanism for processing input/output requests. For example, a priority change processing unit 3 receives a priority change request from an external device such as the operator console 28 and changes the priority set in the task control table 6; An input/output controller (input/output control mechanism) 5 that receives input/output requests and processes the input/output requests is provided as a main component.

The input/output request issued from the user program 4 is accepted by the input/output controller 5, and if the input/output request has a priority schedule, the input/output request is received by the input/output controller 5.
refers to the task control table 6, sets the task priority of the task as the priority of the input/output request, schedules the input/output request, and ranks the input/output request in a predetermined order in the input/output request management table 7 according to the ranking according to the schedule processing. set. In the scheduling process of input/output requests, if input/output requests are accepted in the order of first-in, first-out, a predetermined priority code that specifies the first-in, first-out method is used as the input/output priority. Schedule processing of input/output requests using the method. Examples of the task priority and input/output priority codes used here are shown in FIGS. 2a and 2b.

The input/output request management table 7 set here is as follows:
It is chained from the physical device table 8 and physical device expansion table 9 corresponding to each input/output device 2. The physical device table 8 is a control table for managing operations of input/output devices, and the physical device expansion table 9 is a control table for managing error states of input/output devices.

FIG. 3 is a diagram illustrating the reference relationship of each control table when processing an input/output request.

Continuing the explanation with reference to FIG. 3, the input/output control mechanism (input/output controller 5) sequentially inputs/outputs from the input/output requests in the input/output request management table 7 chained to the top of the physical device expansion table 9. Processes output requests.

The process of registering input/output requests in the input/output request management table 7 performed by the input/output controller 5 is performed based on the priority of each input/output request that has already been sent to the cellar I as the input/output request management table 7. Physical device expansion table 9
Compare the input/output coupler priority of the input/output request management table 7 that is chained from the input/output request management table 7 with the accepted input/output request, and follow the chain until the input/output coupler priority of the input/output request management table is higher than the accepted input/output request. . If an input/output request management table that registers an input/output request with a lower input/output priority than the accepted input/output request is found, the accepted input/output request will be set in the input/output request management table at the immediately previous rank. Change the chain to . Furthermore, if an input/output request table with a lower input/output priority than the input/output priority of the received input/output request is not found, the input/output request management table of the input/output request received at the end of the chain is chained.

The task control table 6 is used by the input/output controller 1-controller 5 to process priority schedules.

The task control table 6 is a control table that is generated when a task is generated for executing a processing program, and has priorities set for the task. The priority of the task control table set here is
It can be updated by the priority change processing section 3 in response to a priority change request from the operator console 2a). For example, when a priority change request from an operator is input from the operator console 2a, the priority change processing section 3 receives it and updates the task priority in the task control table 6 based on the requested priority.

Next, another embodiment of the present invention will be described. The input/output schedule performed here depends on the initial settings at the time of system generation, and either the reception of input/output requests is performed in a schedule that determines the order of input/output processing, or the task that issues the input/output request has priority. It may be possible to select whether to perform a schedule process that determines the priority of input/output processes according to the order. In the input/output schedule processing in which input/output requests are accepted in order, input/output processing is performed to create channel queues.

FIG. 4 is a block diagram showing the main structure of a data processing system according to another embodiment of the present invention, mainly showing processing elements. In FIG. 4, 31 is an operator console;
32 is a task priority control process, 33 is a processing program, and 34 is a task control block (TCB)
, 35 is a task dispatcher. The task dispatcher 35 performs dispatch processing to give control of the processing device to each task according to the priority set in the task control block 34. The dispatched processing program 33 gains control of the processing device and executes the processing. In the task priority control process 32, the priority set in the task control block 34 is changed in response to a priority change request from the operator console 31 or the processing program 33. When an input/output processing request occurs in the processing program 33, the processing program issues EXCP
A macro instruction is issued to a control program (not shown);
The input/output controller 40 is a control program that controls processing.
Move to.

The input/output controller 40 receives an input/output request (EXCP macro command) from the processing program 33 in a process 41, and schedules input/output processing for the received input/output request. In the next input/output request queue reorganization process 42, the priority set in the task control block 34 is referred to, and the input/output request is scheduled in the corresponding input/output order. That is, reorganization processing of the set input/output request queue is performed. Then, for example, when the activation conditions for the input/output device are met, an input/output request activation process 43 is performed to activate the input/output device 44. When the predetermined input/output processing is completed in the input/output device 44,
The input/output device 44 issues an input/output interrupt signal. When an input/output interrupt signal is generated from the input/output device 44, the input/output interrupt processing 45 performs the input/output interrupt processing, and depending on the content of the input/output interrupt signal, the control of the processing is directly transferred to the completion reporting processing 47, or Alternatively, after performing the error recovery process 46, proceed to the completion report process 47, or if a retry is to be performed based on the processing result in the error recovery process 46, control of the process is transferred again to the input/output request activation process 43,
Processing will proceed. In the completion report processing 47, a completion report is sent to the processing program 33 based on the processing result of the input/output request processing.

FIG. 5 is a flowchart showing the processing flow of input/output request queue reorganization processing for scheduling input/output requests. This process is a process flow performed by the input/output request queue reorganization process 42 in FIG. This will be explained with reference to FIG. In the input/output scheduling process here, first, in step 50, an entry for an input/output request queue is created. In this entry creation process, the address of the CCB, the input/output priority of the input/output request, etc. are stored in order to refer to the preset priorities. Next, the process proceeds to step 51, in which the scheduling method set at the time of system generation is determined, and it is determined whether scheduling processing is to be performed using the priority scheduling method based on task priority order, or scheduling processing based on the FIFO method where reception is sequential. If the scheduling process is based on the FIFO method, in step 52, in order to chain the current input/output request queue to the end of the chain of input/output request queues, the relevant input/output request is set at the end of the input/output request queue. Finish schedule processing.

If the determination in step 51 is that the schedule processing is based on the priority scheduling method, then in step 53, the head of the input/output request queue chained to the physical device table and physical device extension table corresponding to the device to which the input/output request has been issued is demand. Next, in step 54, it is determined whether the input/output request of the input/output queue determined in step 53 is being executed. If it is running, step 55 asks for the next input/output request queue, and the next step 56
to determine whether there is a next I/O request queue. If it is determined in step 56 that there is no next input/output request queue, the process proceeds to step 58, and in order to chain the current input/output queue after the obtained input/output request queue, a new input/output queue is added to the end of the input/output request queue. Set the output request and end the schedule processing.

On the other hand, in step 54, if the input/output request of the determined input/output queue is not being executed, priority comparison can be performed, so the process proceeds to step 57. However, step 55
In the process of step 56, if there is a next input/output request queue, the priorities can be compared, so the process proceeds to step 57, and the priority of the old input/output request queue that has already been scheduled is compared with the priority of the current input/output request queue. Compare the priority of the new I/O request to be scheduled. As a result of the priority comparison, if the priority of the new I/O request is not high, there is no need to change the priority settings of the old I/O request queue being compared here, so the process returns to step 55 and another old I/O request is Similar processing is repeated to determine whether or not there is a change in the priority setting for the output request queue. In the priority comparison determination process in step 57, if the new input/output request has a higher priority, in order to change the priority setting of the relevant input/output request queue, in step 59,
In order to chain the current input/output queue before the obtained input/output request queue, a new input request is inserted and set at the corresponding position, and the schedule processing is completed.

The present invention has been specifically explained above based on examples, but
It goes without saying that the present invention is not limited to the embodiments described above, and can be modified in various ways without departing from the spirit thereof.

〔Effect of the invention〕

As described above, according to the present invention, the input/output schedule control means controls each program in order to perform the input/output schedule that determines the priority of input/output processing according to the task priority of the task issuing the input/output request. Regarding input/output requests, the processing order of the input/output requests is determined based on the priority of the task control table. therefore,
The priority of input/output request processing is determined based on the task priority of the task control table, and input/output processing is performed, so a program with a high priority is given a high priority in the processing of input/output requests. This can improve the overall throughput of high-priority programs.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the system configuration of main parts of a data processing system according to an embodiment of the present invention, and FIGS. 2a and 2b show examples of codes for each of task priority and input/output priority. FIG. FIG. 3 is a diagram illustrating the reference relationship of each control table when processing input/output requests, and FIG. 4 shows the configuration of the main parts of a data processing system according to another embodiment of the invention.
FIG. 5 is a block diagram mainly showing processing elements. FIG. 5 is a flowchart showing a processing flow of input/output request queue reorganization processing for scheduling input/output requests. In the figure, 1... central processing unit, 2... input/output device, 2a...
- Operator console, 3...Priority change processing unit, 4...User program, death input/output controller (input/output control mechanism), 6...Task control table, 7
...I/O request management table, 8..Physical device table, 9..Physical device expansion table.

Claims (1)

[Claims] 1. Input/output control that receives each input/output request, performs an input/output schedule that creates a queue for each input/output request, and processes each input/output request according to the order of the input/output schedule. What is claimed is: 1. A data processing system comprising: an input/output schedule control means for performing a scheduling process that determines the priority of input/output processing according to the task priority of a task that issues an input/output request. 2. In the data processing system according to claim 1, the input/output schedule control means performs a scheduling process that determines the order of input/output processing based on the order in which input/output requests are received, according to initial settings at the time of system generation, or A data processing system that selects whether to perform scheduling processing that determines the priority of input/output processing according to the task priority of a task that issues an input/output request. 3. In the data processing system according to claim 1, the change of the input/output schedule by the input/output schedule control means is performed by changing the priority of the user task by an external command, and the priority of the input/output processing is changed. An input/output scheduling method for a data processing system characterized by: