JP2001331331A - Unique process multithread operating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in the conventional systems that throughput or a response is poor because process switching occurs during the execution of an application process and a system process. SOLUTION: An IPL part 100 which is an initial setting when a computer is started has a unique process generation means 101 and a resident system thread generation means 102, and a unique process shutdown part 130 to be shut down, when the computer is halted has a unique process halt means 131. Thereby a unique process in the system is generated when the computer is started, and the constitutional elements of an operating system are realized as threads in the process. A process management part 120 has an application thread start means 121, and an application program also is executed as a thread in the unique process so that switching of processes is not generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for improving overhead caused by process switching, and more particularly to a single process multithread operating system in which a program including an operating system operates as a thread under a single process in a system.

[0002]

2. Description of the Related Art An example of a conventional operating system has been commercialized as "Inside Win".
dowsNT (registered trademark of Microsoft Corporation) "and, as a special case," JP-A-10-055284 "which relates to efficient thread scheduling in a multiprocessor configuration.

As shown in FIG. 9, a conventional process scheduler of an operating system includes a process switching unit (process dispatcher), a process generation unit, and a process deletion unit.

A conventional operating system having such a configuration operates as follows with reference to FIG.

That is, when the computer is started, the IP
In L900, a resident system process is generated, and when an interrupt occurs due to a time slice, the interrupt handler 910 switches the process by the process switching unit 945. Here, after the process is switched, the thread is switched next, and the logical space is also switched. In addition, the application was started by the program management 920 as a single process by the process generation unit 945.

This prior art has the following advantages because the address space of the logical (virtual) memory is independent for each process.

A first advantage is that the entire address space of the logical (virtual) memory can be used for each process. That is, a large logical space can be occupied for each application.

[0008] The second advantage is that since no other process space can be accessed, it is strong against unauthorized access and highly reliable.

However, these advantages are effective when an unspecified number of applications are used, and are unnecessary when the computer is used as a machine dedicated to executing a specific completed application. In addition, there is the following problem in trade-off with this advantage.

[0010]

The problem is that the throughput and the response are poor. Reason,
With the increase in functions required of the system, the number of applications that operate simultaneously continues to increase, and process switching between application processes that execute applications and process switching between application processes and system programs (system processes) frequently occur. That's why.

In general, since the overhead required for thread switching is smaller than that of process switching, the present invention eliminates process switching, and uses operating system processes and application programs as the only thread under the process prepared in the system. It is an object of the present invention to solve the above-mentioned problem by causing the operation to be performed so that the process switching is eliminated and only the thread switching is performed.

[0012]

According to a first aspect of the present invention, there is provided a unique process / multithread operating system comprising: a unique process generating means for generating a unique process as a unique process; An IPL that operates at system startup including a resident system thread generating unit that generates as a resident system thread resident in the main memory only under the process, an interrupt request processing unit that performs processing when an interrupt occurs, and an interrupt by a time slice. An interrupt handler including a thread preemption means for changing the assignment of the CPU to another thread when detected, and an application program specified to be started is loaded into a free memory, and is executed as a thread under the sole process. Program management including an application thread starting means to be executed, a shutdown including a unique process terminating means for terminating the sole process in response to a computer stop request, a thread generating means for creating a thread for executing a requested program, and a current The thread scheduler includes thread switching means for interrupting the thread being executed and executing the thread having the highest priority ready for execution and thread deletion means for deleting the thread whose execution has been completed from the system.

[0013] The sole process multi-thread operating system according to the second invention of the present application is the method according to the first invention, wherein a system process constituting the operating system is generated as a thread under the sole process.

A third embodiment of the present invention provides the unique process multi-thread operating system according to the first invention, wherein the application program requested to be started is generated as a thread under the unique process.

The sole process multi-thread operating system according to the fourth aspect of the present invention, in the first aspect, comprises switching only a thread without switching a process.

The sole process multi-thread operating system according to the fifth aspect of the present invention, in the first aspect, does not have a process scheduler for switching a process but only has a thread scheduler for switching a thread under a process. It is prepared.

According to a sixth aspect of the present invention, in the computer according to the first aspect, wherein the computer operates in a real memory space having no virtual storage device, the unique process multi-thread operating system includes: It does not include only the process termination means.

[0018]

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

Referring to FIG. 1, an embodiment of an operating system according to the present invention is an IPL (Initial Program) for performing initial settings at the time of starting a computer.
(Loader) 100, an interrupt handler 110 that analyzes an interrupt and performs an appropriate interrupt process, a program management 120 that starts a requested program as a thread, and a shutdown 1 that stops the computer.
30 and a thread scheduler 140 for controlling the execution of threads in the system.

The IPL 100 includes a unique process creating means 101 for creating a unique process which is a unique process in the entire system, and a resident system thread creating means 102
And

Each of these means operates roughly as follows.

The unique process generating means 101 generates a unique process which is a unique process in the entire system,
Create a logical memory space that is the operating environment for all threads.

The resident system thread generating means 102
Each element constituting the operating system is generated as a resident system thread resident on the main storage memory.

The interrupt handler 110 includes an interrupt request processing unit 111, a thread preemption unit 112
And

Each of these means operates as follows.

The interrupt request processing means 111 generates a thread for processing when the interrupt is the completion of I / O.

The thread preemption means 112
Interrupt is time slice (CP of currently executing thread)
In the case of switching of the thread due to the expiration of the consumption time of U), a request to switch the thread to be executed by the CPU to another thread is made to the thread switching means 142.

The program management 120 includes an application thread starting means 121.

Application thread starting means 121
Generates a thread that loads the application program requested to be started into a free memory and executes it.

The shutdown 130 includes only one process termination unit 131.

The sole process termination means 131 terminates only the process when the system is shut down in response to the request to stop the computer.

The thread scheduler 140 includes a thread generation unit 141, a thread switching unit (thread dispatcher) 142, and a thread deletion unit 143.

Each of these means operates as follows.

The thread generating means 141 generates a thread for executing the requested program or a thread derived from the threaded program.

The thread switching means (thread dispatcher) 142 includes a thread preemption means 112
, The currently executing thread is suspended, and the thread with the highest priority on the Ready queue ready for execution is executed.

The thread deletion means 143 deletes a thread for which program execution has been completed from the system.

Next, the operation of the embodiment of the present invention will be described with reference to the drawings.

The overall operation of this embodiment will be described in detail with reference to FIG. 1 and the flowcharts of FIGS.

First, when the computer is started, the IPL 100 for initializing the system is executed. IPL
In the system initialization process 100, the unique process creation means 101 creates a unique process which is a unique process in the entire system (step A21). Next, the resident system thread generation unit 102 generates, as a thread, a function constituting an operating system including functions such as a memory load control function, a GUI control function, and a communication control function (step A22). Here, the “thread constituting the operating system” conventionally corresponds to a system process, and is not a process but a thread as it is. A program that has been executed as a process can easily be threaded unless the memory is used at a fixed address.
The resident system thread generating means 102 generates a resident system program registered in advance as a system thread resident in the main memory by the thread generating means 141.

When the initialization of the system is completed and the application program is to be started next, the application thread starting means 121 of the program management 120 sets only one thread for executing the application program designated to be started. It is generated under the process (step A31). Again, if the application program, which was previously run as an independent process, does not use memory at fixed addresses,
It is easy to make it the only thread in the process.

When an interrupt occurs, the interrupt handler 1
10 analyzes the cause of the interrupt, and in the case of a time slice (thread switching request) interrupt, the thread that is being executed is interrupted by the thread preemption unit 112 and the thread switching unit 142, and the Ready that accumulates the threads waiting to be executed is stored. The thread with the highest priority in the queue is taken out of the queue and is being executed (step A41). At this time, there is no need to switch the process (switch the logical space). Also, I /
If it is an O-interrupt or an interrupt of a processing request of the other system, the interrupt request processing means 111 generates a thread for processing the request by the thread generating means 141, and sets the thread to a Ready state (step A42).

If the newly created thread has a higher priority than the currently executing thread, the thread generating means 141 switches the execution of the thread by the thread switching means 142.

Finally, when the computer is terminated, the shutdown 130 terminates the only process in the system by the process termination means 131 (step A5).
1).

Next, a specific example will be described.

As shown in FIG. 6, it is assumed that a thread A 604 and a thread B 602 already exist in the system, and a new application program is started there. Application thread starting means 1 of program management 120
21, a thread for executing the application program is generated.
Assuming that the thread B 602 is in the Ready queue 601 of the system and that the thread B 602 is being executed, a newly created application thread 603 is added thereto. Next, when the currently executing thread A 604 causes a time slice and the control is transferred to the interrupt handler 110, the interrupt is detected by the time slice and the control is transferred to the thread preemption means 112.
The thread preemption unit 112 interrupts the running thread A 604 by the thread switching unit 142 and executes the thread with the highest priority in the Ready queue 601. If this is the newly created application thread 603, the application thread 603 is executed. At this time, as shown in FIG.
Is allocated and loaded to a memory not used by the thread A program 702 or the thread B program 704.

Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

This embodiment is different from the first embodiment in that only the process generation means 101 and the only process termination means 13 are provided.
1 is omitted. This assumes a computer that is a multi-programming operating system, but operates in a real memory space without virtual storage. The operation in this case is different from the first embodiment (FIG. 1) in that the process of generating only one process in the IPL 800 and terminating the only process in the shutdown is unnecessary.

[0048]

An advantage of the present invention is that a system with high throughput and high response can be constructed. The reason is that process switching does not occur between application execution and system program (system process) execution.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a first exemplary embodiment of the present invention.

FIG. 2 is a flowchart illustrating a first embodiment of the present invention.

FIG. 3 is a flowchart illustrating a first embodiment of the present invention.

FIG. 4 is a flowchart illustrating a first embodiment of the present invention.

FIG. 5 is a flowchart illustrating a first embodiment of the present invention.

FIG. 6 is a diagram for explaining thread switching under only one process of the present invention.

FIG. 7 is a diagram illustrating allocation of a newly created thread to a logical memory space according to the present invention.

FIG. 8 is a block diagram illustrating a configuration of a second exemplary embodiment of the present invention.

FIG. 9 is a block diagram illustrating a case where a process is switched in a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 100 IPL 101 Only process generation means 102 Resident system thread generation means 110 Interrupt handler 111 Interrupt request processing means 112 Thread preemption means 120 Program management 121 Application thread activation means 130 Shutdown 131 Only process termination means 140 Thread scheduler 141 Thread generation means 142 Thread switching Means 143 Thread deletion means

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoshitaka Marutani 5-3-1 Takatsukadai, Nishi-ku, Kobe-shi, Hyogo F-term (reference) in NEC Corporation 5B098 GA02 GA05 GA08 GC03 GC05 GC14 GD02 GD14

Claims (6)

[Claims] 1. A resident system thread generating means for generating a unique process as a unique process in a system as a unique process creating means and a resident system thread resident in a main storage memory under each unique process under the unique process. And an interrupt request processing means for performing processing when an interrupt occurs, and a thread preemption means for changing the assignment of the CPU to another thread when an interrupt due to a time slice is detected. A program management including a handler, an application thread starting means for loading an application program specified to be started into an empty memory and generating the thread as a thread under the sole process, and a computer stop request. Shutting down the sole process, including the only process termination means, the thread generation means for generating a thread for executing the requested program, and suspending the currently executing thread to prepare the highest execution ready A single process multi-thread operating system, comprising: a thread scheduler including thread switching means for executing a thread having a priority and thread deletion means for deleting a thread whose execution has been completed from the system. 2. The single process multi-thread operating system according to claim 1, wherein a system process constituting the operating system is generated as a thread under the single process. 3. The single process multi-thread operating system according to claim 1, wherein the application program requested to be started is generated as a thread under the single process. 4. The single process multi-thread operating system according to claim 1, wherein only the thread is switched without switching the process. 5. The single-process multi-thread operating system according to claim 1, wherein there is no process scheduler for switching processes, and only a thread scheduler for switching threads under a process is provided. 6. The unique process according to claim 1, wherein the computer operating in a real memory space without a virtual storage device does not include said unique process generating means and said unique process ending means. -Multi-thread operating system.