JPH02211545A - Job execution control system - Google Patents

Abstract

PURPOSE:To reduce overhead due to swapping in a high load state by first starting a virtual space stopped in the high load state when a system resource is in a low load state. CONSTITUTION:When the system resource is in the low load state, and a job waiting for an execution exists in a job group 4a, the job in an execution class at the highest priority is selected, a virtual space C for the execution class is newly prepared, and a job 1c is executed. At the time of the high load, the virtual space where the job is not executed is stopped, the job in the execution class at the lowest priority is selected, and after the job is completed, the executed virtual space is stopped. When the load of the system resource is in an allowable range, the virtual space stopped at the time of the high load is started, and in the low load state, the newly prepared virtual space is erased. Thus the overhead due to the swapping in the high load state can be reduced, and the idle state of the system resource in the low load state can be canceled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a job execution control method in a control program for a computer system.

[Prior Art] FIG. 3 is a block diagram showing a conventional job control method. Figure 3 shows the central processing unit (CPU).

This figure shows a conventional job control method using swapping when the load on system resources such as the main storage device and channels is high. In the figure, 1 is a virtual storage device, 1a is a job being executed in virtual space A, 1b is a job being executed in virtual space B, 2 is a main storage device, 2a is a group of jobs being executed, and 3 is an external storage device. , 3a is a group of jobs being swapped out to the external storage device 3.

Next, the operation of the conventional job control method described above will be explained. If the system resources are under high load, the job that has the greatest impact on the system resource load is selected from the currently executing job group 2a and swapped out to the external storage device 3. Also, job group 3a that is being swapped out
In order to prevent system resources from being distributed unbalanced to job group 2a that is currently being executed, job group 3a that is being swapped out
An exchange swap is performed between a and the job group 2a that is being executed.

However, even when system resources are under low load, a new virtual space for batch jobs is created and jobs are not executed in the virtual space.

[Problem to be Solved by the Invention] In the conventional job control method as described above, the sum of the number of jobs in the job group 2a that is being executed and the number of jobs in the job group 3a that are being swapped out is the virtual space. If the system resources are under high load, swapping will occur among these jobs. In addition, if the number of virtual spaces is fixed, the overhead caused by swapping cannot be ignored if the system resources are under a high load at a certain time, and conversely, the system resources may be under a low load for a long period of time. If this continues, there are problems such as system resources becoming idle.

This invention was made to solve the above-mentioned problems. When system resources are under a high load, it is possible to reduce the number of virtual spaces and reduce the overhead caused by swapping. In some cases, the objective is to obtain a job execution control method that increases the number of virtual spaces and eliminates the idle state of system resources.

[Means for Solving the Problems] A job execution control method according to the present invention reduces the number of virtual spaces for batch jobs when system resources are in a high load state, and also reduces the number of virtual spaces for batch jobs when system resources are in a low load state. If there is a virtual space that was stopped when the resource was under high load,
These are started first, and if there is room and there are jobs waiting to be executed, the number of virtual spaces for batch jobs is increased.

[Operation] The job execution control method according to the present invention reduces the load on system resources by reducing the number of reflection spaces for batch jobs when system resources are under high load.
If the system resources are in a low load state and there are jobs waiting to be executed, increasing the virtual space for batch jobs will increase the load on the system resources.

[Embodiment] FIG. 1 is a block diagram showing a job execution control system according to an embodiment of the present invention. In the figure, 1 is a virtual storage device, 1a is a job being executed in virtual space A, 1b is a job being executed in virtual space B, 1c is a job being executed in a newly created virtual space C, and 2 is the main job. Storage device, 2a is a group of jobs being executed, 3 is an external storage device, 3a is a group of jobs being swapped out to the external storage device 3, 4 is a spool area, 4a
is a group of jobs waiting to be executed.

FIG. 2 is a flowchart for explaining the operation of the job execution control method shown in FIG. FIG. 2 is a flowchart showing a process for monitoring the load status of system resources and periodically controlling job execution. In the figure, 5 to 13
are steps showing the processing process.

Next, the operation of the job execution control method according to the embodiment of the present invention will be explained with reference to the flowchart shown in FIG. If the system resources are under low load, check whether there is a job waiting to be executed in the job group 4a waiting to be executed, and if there is a job waiting to be executed, the priority Select a job with a high execution class, create a new job 1c running in virtual space C for the execution class, and execute the job (
Steps 5-7).

If system resources are under high load, stop the virtual space in which no jobs are currently being executed, select the job with the lowest priority execution class from the currently executing job group 2a, and terminate the job. Afterwards, the virtual space in which the job was being executed is stopped (steps 5 and 8).

If the load on the system resources is within the allowable range, the virtual space that was previously stopped when the system resources were in a high load state is started (steps 5.9 to 11). Furthermore, when the system resources were previously in a low load state, if there is a newly created virtual space, that virtual space is deleted (steps 5 and 9, 10.12.13).

[Effects of the Invention] As described above, according to the job execution control method of the present invention, the number of virtual spaces for batch jobs can be reduced when system resources are in a high load state, and the number of virtual spaces for batch jobs can be reduced when system resources are in a low load state. If there are virtual spaces that were stopped when system resources were under high load, start them first, and if there is free space and there are jobs waiting to be executed, increase the number of virtual spaces for batch jobs. As a result, the overhead due to swapping can be reduced when system resources are under high load, and the idle state of system resources can be eliminated when system resources are under low load. be.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a job execution control method according to an embodiment of the present invention, FIG. 2 is a flowchart for explaining the operation of the job execution control method shown in FIG. 1, and FIG. 3 is a conventional job control method. FIG. In the figure, 1...virtual storage device, 1a...job running in virtual space A, lb...job running in virtual space B, 1c...job running in virtual space C, 2
...Main storage device, 2a...Group of jobs being executed, 3.
. . . External storage device, 3a . . . Job group being swapped out, 4 . . . Spool area, 4a . . . Job group waiting for execution, 5 to 13 . . . Steps. In addition, the same symbols in the figures indicate the same or equivalent parts. Figure 2

Claims (1)

[Claims] Batch jobs are divided into execution classes based on priority, the virtual space in which the job is executed corresponds to the execution class, and the job of the execution class corresponding to the virtual space that is not currently being executed is removed from the execution queue. In a computer system, the computer system includes means for searching and executing jobs in the virtual space, and means for periodically monitoring the load on system resources such as a central processing unit, main storage, and channels, and controlling job execution mainly by swapping. If the load on the above system resources is low for more than a certain period of time and there are jobs waiting to be executed, search for jobs waiting to be executed from the execution class with the highest priority and create a new virtual space for the execution class of the job. However, if the load on the system resources is high for more than a certain period of time and there are jobs being executed, the virtual space where no jobs are currently being executed is stopped and the current The virtual space will be stopped when the execution class job with the lowest priority among the running jobs has finished, and when the load on the system resources has recovered to an acceptable range,
The number of executable jobs is controlled according to the load status of the system resources by erasing a newly created virtual space when the load is low and starting a virtual space that was stopped when the load is high. Job execution control method.