JPH1031592A - Method and system for managing memory - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a memory managing system capable of evading the deadlock of a program due to the reduction of memory resources, the malfunction of a computer and the decrease of processing speed due to memory swapping without caring about an application program. SOLUTION: The system is provided with an operating system 20 for performing an execution control of tasks or processes based on the application program 100 including plural tasks or processes set as an independent unit of program operation in a software of a real time processing computer in program groups 101, 102 and a memory 10 used by the task or the process, and the operating system 20 is provided with a memory consumption counting means 20a as a memory monitoring means for monitoring memory resources, a mode for changing a schedule of the task or the process and a mode for waiting the execution control for the tasks or the processes according to the monitoring result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a memory management method for controlling a memory resource used by a task or a process executed and controlled by an operating system of a real-time processing computer, and a memory management system to which the method is applied.

[0002]

2. Description of the Related Art Conventionally, in a memory management system of this type, an operating system for controlling execution of a task or a process based on an application program including a task or a process which is an independent unit of a program operation by software of a real-time processing computer. , Memory used by the task or process.

When memory management is performed by such a memory management system, an operating system can dynamically use a memory by an application program including tasks or processes.

[0004]

In the above-described memory management method using the memory management system, when the operating system dynamically uses the memory by an application program including tasks or processes,
If the application program is not involved in the amount of memory consumption at all and there is an input that cannot keep up with the processing speed, there is a problem that the processing speed is likely to be reduced due to program deadlock, computer inoperability or memory swap.

[0005] Further, even when the application program considers the memory consumption, programming that is conscious of the memory consumption is required, and complicated processing is required.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and its technical problems are that a program deadlock due to a decrease in memory resources, computer inoperability and computer inoperability can occur without the application program being conscious of it. An object of the present invention is to provide a memory management method and a memory management system capable of avoiding a reduction in processing speed due to a memory swap.

[0007]

According to the present invention, an operating system for controlling execution of a task or process, which is an independent unit of program operation, by software of a real-time processing computer is dynamically used by the task or process. Monitoring the memory resources
Rescheduling the task or the process, or consuming the memory, until the memory consumption related to the memory resource exceeds a preset first alert threshold and recovers to a first recovery threshold. The second quantity is preset
A memory management method is provided in which the execution control of the task or the process is suspended until the alarm reaches the second recovery threshold after exceeding the alarm threshold.

On the other hand, according to the present invention, an operating system for controlling execution of a task or a process based on an application program including a task or a process which is an independent unit of a program operation by software of a real-time processing computer; In a memory management system having a memory used by a process, a memory management system having a memory monitoring means for an operating system to monitor memory resources is obtained.

Further, according to the present invention, in the above-mentioned memory management system, the operating system allows the memory recovery amount to exceed the first alarm threshold value set in advance according to the monitoring result by the memory monitoring means, and to perform the first recovery. A rescheduling mode for rescheduling a task or a process until the threshold value is restored, and a rescheduling mode for resuming the memory consumption to a second recovery threshold value after exceeding a preset second alarm threshold value. A memory management system having an execution control standby mode for waiting for execution control of a task or a process is obtained.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

First, the outline of the memory management method of the present invention will be briefly described. This memory management method uses a memory of a real-time processing computer as a result of an operating system that controls execution of a task or a process, which is an independent unit of a program operation, dynamically monitoring a memory resource used by the task or the process. Rescheduling a task or process until the memory consumption for the resources of the first or second resource exceeds a first preset alarm threshold and recovers to a first recovery threshold,
Alternatively, the execution control of the task or the process is waited until the memory consumption exceeds the preset second alarm threshold and recovers to the second recovery threshold.

This makes it possible to avoid a deadlock of a program due to a decrease in memory resources, an inoperability of a computer, and a reduction in processing speed due to a memory swap, without the application program being conscious of it.

FIG. 1 is a block diagram showing a basic configuration of a memory management system according to an embodiment to which the memory management method is applied.

This memory management system controls the execution of a task or a process based on an application program 100 including a plurality of tasks or processes, which are independent units of the program operation, in software groups of a real-time processing computer in program groups 101 and 102, respectively. An operating system 20 and a memory 10 used by a task or a process. The operating system 20 includes a memory consumption measuring unit 20 as a memory monitoring unit for monitoring a memory resource.
a.

Further, the operating system 20 includes:
The task or process schedule is changed until the consumption of the memory 10 exceeds the preset first alarm threshold and recovers to the first recovery threshold according to the monitoring result by the memory consumption measuring unit 20a. Wait for the task or process execution control until the schedule change mode (method 1) and the consumption of the memory 10 exceeds the preset second warning threshold and recovers to the second recovery threshold. An execution control standby mode (method 2).

Of these, the application program 1
Each task or process in the program group 101 of 00 is mainly caused by consumption of the memory 10 due to an event from the outside, and each task or process in the program group 102 is finalized in a series of processing. The processing is performed and the contents of the memory 10 are mainly released. Incidentally, the application program 100 and the operating system 20
The operation program can be regarded as computer software.

FIG. 2 shows the characteristics of the memory consumption ΔM with respect to the transition of the time t shown for explaining the memory resource control by the operating system 20.

Here, when a task or process dynamically issues an acquisition request to the memory 10, the first alarm threshold (M 1) in the memory consumption △ M is determined with respect to the physical capacity M _max of the memory 10. , A larger consumption, the second
Alarm threshold (M2), a first memory recovery threshold (M3) that can determine that the first alarm threshold (M1) has recovered, and a second memory threshold that can determine that the second alarm threshold (M2) has recovered. A memory recovery threshold (M4) is provided, and each time the operating system 20 receives a memory acquisition / release request for the memory 10 from the application program 100, the total amount of the memory 10 currently consumed is measured by the memory consumption measuring means 20a.

When the result of the memory consumption ΔM obtained by the memory consumption measuring means 20a becomes larger than the first alarm threshold value (M1), the operating system 20 executes each process or task in order to suppress the memory consumption. The method is switched to the method 1 in which the program group 102, which operates mainly with the release of the memory 10, is executed with priority over the program group 101.

The switching here is terminated when the memory consumption ΔM becomes smaller than the first memory recovery threshold value (M3), and thereafter the operation is switched back to the normal allocation method.

Further, the operating system 20 includes:
In the state of the execution allocation method 1, when the result of the memory consumption ΔM by the memory consumption measuring means 20a becomes larger than the second alarm threshold (M2), the program group 101 is set to stop the memory consumption. Is switched to method 2 in which execution is not assigned to.

In this switching, the memory consumption is the second.
Is terminated when the memory recovery threshold value (M4) is smaller than the memory recovery threshold value (M4).

[0023]

As described above, according to the present invention, an operating system that controls the execution of a task or process, which is an independent unit of program operation, by software of a real-time processing computer is dynamically used by the task or process. The task or process schedule is changed or the execution control of the task or process is changed according to the result of monitoring the memory resources to be executed. Deadlock, inoperability of the computer, and reduction in processing speed due to memory swap can be avoided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of a memory management system according to an embodiment to which a memory management method of the present invention is applied.

FIG. 2 is a time transition characteristic of memory consumption shown for explaining memory resource control by an operating system of the memory management system shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Memory 20 Operating system 20a Memory consumption measuring means 100 Application program 101,102 Program group

Claims (3)

[Claims] An operating system that controls execution of a task or a process, which is an independent unit of a program operation, by software of a real-time processing computer dynamically monitors memory resources used by the task or the process. Changing the schedule of the task or the process, or the memory consumption, until the memory consumption related to the memory resource exceeds the preset first alarm threshold and recovers to the first recovery threshold. Memory management method, wherein the execution control of the task or the process is suspended until the data exceeds the second alarm threshold set in advance and recovers to the second recovery threshold. 2. An operating system for controlling execution of a task or a process based on an application program including a task or a process which is an independent unit of a program operation by software of a real-time processing computer, and used by the task or the process. Memory management system having a memory
A memory management system, wherein the operating system includes a memory monitoring unit for monitoring resources of the memory. 3. The memory management system according to claim 2, wherein the operating system determines that the memory consumption exceeds a first alarm threshold set in advance according to a monitoring result by the memory monitoring means. A schedule change mode for changing the schedule of the task or the process until the recovery to the recovery threshold, and the memory consumption recovers to the second recovery threshold beyond the second alarm threshold set in advance. An execution control standby mode for waiting for execution control of the task or the process until the execution of the memory management system.