Multiprogramming Operating System Research Articles

Comparative analysis of the essential CPU scheduling algorithms

CPU scheduling algorithms have a significant function in multiprogramming operating systems. When the CPU scheduling is effective a high rate of computation could be done correctly and also the system will maintain in a stable state. As well as, CPU scheduling algorithms are the main service in the operating systems that fulfill the maximum utilization of the CPU. This paper aims to compare the characteristics of the CPU scheduling algorithms towards which one is the best algorithm for gaining a higher CPU utilization. The comparison has been done between ten scheduling algorithms with presenting different parameters, such as performance, algorithm’s complexity, algorithm’s problem, average waiting times, algorithm’s advantages-disadvantages, allocation way, etc. The main purpose of the article is to analyze the CPU scheduler in such a way that suits the scheduling goals. However, knowing the algorithm type which is most suitable for a particular situation by showing its full properties.

CPU Scheduling Techniques: A Review on Novel Approaches Strategy and Performance Assessment

The operating system (OS) is now being widely used in many of the various modern applications in recent years, ranging from diabetic monitoring to other strategic planning. The main function of any OS is to control and coordinate all hardware resources among the commands of the same/different user, which increases the efficiency of advanced comprehensive applications. In an autonomous computer system, the CPU is one of the important resources to manage and process all activities which require scheduling techniques on a processor. Since the early days of computing and other multi-programming OS, various studies have been assigned to CPU scheduling techniques based on processes management and performance evaluation. Thus, outlining the many issues related to scheduling methodologies and the weaknesses that need to be addressed. This review paper is organized based on two distinct perspectives: the implement strategies of CPU scheduling technique and criteria-based measures used, which assess how the strategies are analyzed and used under performance evaluation.

A Neural Net-Based Approach for CPU Utilization

CPU scheduling is an important subject to maximize CPU utilization in the context of operating systems. Multiprogramming operating systems need CPU scheduling for organization of processes to be executed. The order of process execution is determined by a CPU scheduling policy in use. The utilization of CPU depends on the selection of scheduling algorithms. There are several scheduling policies in the literature such as First-Come, First-Served scheduling, Shortest-Job-First scheduling, Last-Come, First-Served scheduling, Priority scheduling. On the other hand, there are some criteria (waiting time, throughput number, turnaround time, response time) to measure the eficiency of these policies. It is important that we choose the scheduling policy which has the minimum waiting time as this is crucial stage of utilizing CPU efficiently. This paper explores an alternative, neural network approach to build a CPU scheduling model to obtain the waiting time measure. In this paper, we will show that neural networks can be used to model scheduling policies and can predict the waiting time of processes. Three learning algorithms and three different neuron numbers in the hidden layer of the network are studied to boost the eficiency of neural network model for waiting time prediction. A comparison between Neural-Network Based Model and First-Come, First-Served scheduling, Shortest-Job-First scheduling, Last-Come, First-Served scheduling are provided. The results reveal the effectiveness of neural networks in predicting waiting times, and thus suggest that it can be useful and practical addition to the framework of operating systems.

Time Quantum based CPU Scheduling Algorithm

The objective of this paper is to introduce a new CPU Scheduling Algorithm called time quantum based CPU Scheduling Algorithm which acts as preemptive based on the arrival time. The algorithm helps to improve the average waiting time of Round Robin algorithm in real time uniprocessor-multi programming operating system. CPU Scheduling is the basis of multi-programmed operating system. The scheduler is responsible for multiplexing processes on the CPU. There are many scheduling algorithms available for a multi-programmed operating system like FCFS, SJF, Priority, Round Robin etc. The proposed algorithm is based on Round robin scheduling . In this paper, the results of the existing Round Robin algorithm is compared with the proposed algorithm General Terms CPU Scheduling Algorithms, Context Switching.

CAPS: A TOOL FOR PROCESS SCHEDULING

A multiprogramming operating system allows more than one process to be loaded into the main-memory at a time and allows the loaded process to share the CPU using time-multiplexing. CPU scheduling is the method of determining when processors should be assigned and to which processes. CPU scheduling in distributed system can be defined as allocating processes to processors so that total execution time will be minimized, utilization of processors will be maximized and load balancing will be maximized. This paper presents a simulating behavior of CPU scheduling in distributed environment using the proposed and developed Computing Analyzer and Process Simulator (CAPS) tool. Symmetric multiprocessor scheduling technique has been implemented in the presented CAPS tool and the selection of the processes from the ready queue is done through the FCFS scheduling policy. The hard affinity mechanism has been implemented where processes are restricted to migrate among processors. Once a process has been allocated to a CPU, it will complete its execution on that processor only. The implementation of CAPS tool is done through Microsoft Visual Studio 9.0.

CPU Scheduling Visualization

Scheduling is a key concept in computer multitasking and multiprocessing operating system design, and in real-time operating system design. CPU scheduling is the basis of multiprogramming operating systems by switching the CPU among process; the operating system can make the computer more productive, scheduling algorithms are widely used in communications networks and in operating systems to allocate resources to competing tasks. In this paper, visual interfaces for CPU scheduling algorithms were designed by using Visual Basic6 language. They may use to learn users about this algorithms and how they work

An Optimized Approach to CPU Scheduling Algorithm: Min-max

CPU scheduling is the basis of multi-programmed operating systems. The scheduler is accountable for multiplexing processes on the CPU. By switching the CPU among processes, the operating system results in the computer more prolific. Various CPU scheduling algorithms exist for a multi-programmed operating system like First Come First Served (FCFS), Shortest Job First (SJF), Shortest Remaining Time Next (SRTN) and Round Robin (RR) scheduling algorithm. This paper has threefold objective. Firstly, it throws light on a new-fangled CPU scheduling algorithm called MIN-MAX whichbehaves as both preemptive and non-preemptive algorithm basis on the burst time. Secondly, it would helps to understand how MIN-MAXalgorithm improves the CPU efficiency in multi programming operating system and also trims down the starvation problem amongprocesses. Thirdly, it focuses on the comparative study of the existing algorithms on basis of various scheduling parameters with the proposed algorithm MIN-MAX.

An Improved CPU Scheduling Algorithm

In multiprogramming systems i.e. in systems where several processes reside in memory, organization of processes is very important so that CPU always has one to execute. CPU scheduling is the base of multiprogramming operating systems. CPU executes one process at a time and switches between processes to improve CPU utilization. CPU scheduling strategies help in selecting the next process to be executed by the CPU. CPU scheduling is one of the most important activities performed by operating system which helps in increasing the throughput of the computer system therefore if the performance of scheduling will improve then our computer system will become more productive. In this paper, CPU scheduling algorithm with improved performance has been proposed. The technique which is used for increasing the speed up factor is ‘Pipelining’. This technique can be applied to any CPU scheduling algorithm to improve its performance. The analysis shows that the proposed algorithm is better than the existing scheduling algorithms. The performance is improved by 40-50%. General Terms CPU Scheduler, Scheduling algorithm, Process, etc.

A New Method to Improve Round Robin Scheduling Algorithm with Quantum Time Based on Harmonic-Arithmetic Mean (HARM)

One of the most important concepts in multi programming Operating Systems is scheduling. It helps in choosing the processes for execution. Round robin method is one of the most important algorithms in scheduling. It is the most popular algorithm due to its fairness and starvation free nature towards the processes, which is achieved by using proper quantum time. The main challenge in this algorithm is selection of quantum time. This parameter affects on average Waiting Time and average Turnaround Time in execution queue. As the quantum time is static, it causes less context switching in case of high quantum time and high context switching in case of less quantum time. Increasing context switch leads to high average waiting time, high average turnaround time which is an overhead and degrades the system performance. With respect to these points, the algorithms should calculate proper value for the quantum time. Two main classes of algorithms that are proposed to calculate the quantum time include static and dynamic methods. In static methods quantum time is fixed during the scheduling. Dynamic algorithms are one of these methods that change the value of quantum time in each cycle. For example in one method the value of quantum time in each cycle is equal to the median of burst times of processes in ready queue and for another method this value is equal to arithmetic mean of burst times of ready processes. In this paper we proposed a new method to obtaining quantum time in each cycle based on arithmetic- harmonic mean (HARM). Harmonic mean is calculated by dividing the number of observations by the reciprocal of each number in the series. With examples we show that in some cases it can provides better scheduling criteria and improves the average Turnaround Time and average Waiting Time.

OS project implementation

This paper describes the implementation of a Multi-Programming Batch Operating System (MOS) project [3] using threads. Two other papers [7, 8], both of which include issues from earlier implementat...

Simulation-based comparison of scheduling techniques in multiprogramming operating systems on single and multi-core processors

The operating systems course is one of the essential courses in the computer science curriculum, and CPU scheduling is a crucial component of this course. Multi-core processors have become the norm...

CPU SCHEDULING SIMULATION

CPU scheduling is the basis of multiprogrammed operating system. By switching the CPU among processes, the operating system can make the computer more productive. The objective of multiprogramming is to have some process running at all times, in order to maximize CPU utilization. This paper presents a simulator that uses graphical representation to convey the concepts of various scheduling algorithms for a single CPU. It allows the user to test and increase his understanding of the concepts studied by making his own scheduling decisions, through the very easy graphical user interface of the simulator. It graphically depicts each process in terms of what the process is currently doing against time. Using this representation it becomes much easier to understand what is going on inside the system and why different set of processes are candidate for allocation of the CPU at different time.In this paper, we introduce the basic scheduling concepts and present several different CPU – scheduling algorithms in visual way.

Multichannel real-time data acquisition system using dual ported FIFO buffers

In contrast to real-time data acquisition systems employing a minicomputer with a real-time multiprogramming operating system, this paper describes the design and development of a high throughput data acquisition system using an IBM compatible PC/AT, high speed sampling A/D converter, and dual ported FIFO RAM buffers, in the MS-DOS environment. Data acquisition software is developed in Turbo Pascal with a few in-line machine language procedures.

Flow control for limited buffer multicast

Analyses a multiround flow control algorithm that attempts to minimize the time required to multicast a message to a group of recipients and receive responses directly from each group member. Such a flow control algorithm may be necessary because the hurry of responses to the multicast can overflow the buffer space of the process that issued the multicast. The condition that each recipient directly respond to the multicast prevents the use of reliable multicast protocols based on software combining trees or negative-acknowledgments. The flow control analysed algorithm directs the responding processes to hold their responses for some period of time, called the backoff time, before sending them to the originator. The backoff time depends on the number of recipients that respond, the originator's available buffer space and buffer service time distribution, and the number of times that the originator is willing to retransmit its message. This paper develops an approximate analysis of the service time distribution of the limited-buffer preemptive queuing process that occurs within the protocol processing layers of a multiprogrammed operating system. It then uses this model to calculate multicast backoff times. The paper reports experimental verification of the accuracy of this service time model and discusses its application to the multicast flow control problem. >

Simulation of process and resource management in a multiprogramming operating system

Simulation of process and resource management in a multiprogramming operating system

MPX-PC: an operating system project for the PC

This paper describes a student operating system project, MPX-PC, that can be implemented on an IBM PC-compatible computer. Seven modules make up the project, with the seventh module being the completion of a “stand-alone” student multiprogramming operating system. The project is implemented in Turbo C.

A priority queue with interruptions of service permitted after a time quantum

The queueing theory is applied to analyse a model of a multiprogramming operating system in which preemptive priorities are used for scheduling the service of concurrent streams of requests. Preemptions are permitted at the end of each service quantum. Mean waiting times and higher statistical moments in the M/G/1 system analysed are computed.

The Control System for the Dedicated Synchrotron Radiation Storage Ring Bessy

BESSY is a 800 MeV electron-storage ring dedicated to research with synchrotron radiation in the VUV and soft X-ray region. The storage ring is fed by a 800 MeV separated function synchrotron with a clasical 20 MeV microtron as preinjector. The machines are remotely controlled by four minicomputers which are linked by a local network. The computers are connected to a commercially available electronic interface system. The general philosophy for the system design was determined by boundary conditions such as reliable processor hardware, reliable and powerful multi-user multi-programming real-time operating systems, well developed software tools, a ready-to-use distributed network with high throughput, compatibility of the electronic interface system, locally available service shops, and, if possible, the avoidance of assembly coding. This paper describes in detail the system which ultimately met these criteria and was subsequently implemented at BESSY.

Using the cyber 205

The CYBER 205 is a new computer systems produced by Control Data Corporation at Arden Hills, Minnesota. The CYBER 205 is a large scale vector processor with substantial capabilities in scaler processing, one-to-four million words of main memory and concurrent I/O facilities. The CYBER 205 is available to potential users now in the last half of 1981. These facilities are found in Control Data CYBERNET Centers as well as in several installations throughout the world. The technology employed in the construction of the CYBER 205 emphasizes the latest advances in large scale integration of both logic and memory. The CYBER 205 system concept exploits the CDC Loosely Coupled Network (LCN). Standard FORTRAN is supplemented by various extensions imbedded with the provided FORTRAN compiler. Arithmetic properties of the computer are designed to support the functional requirements of FORTRAN in 32-bit and 128-bit formats. A multiprogramming operating system based on the CYBER 205 virtual memory isalso provided by Control Data Corporation. A variety of programs have now been run on the CYBER 205. The results of some of these runs are shown in tabular form for parametric study purposes. Analysis of these tables is converted to (tentative) timing formulas applicable to the specific algorithms described. The net effect of the algorithm development, the language support, the CYBER 200 libraries, the input/output support system and the CYBER 200 operational system is to extend the utility of supercomputers in a user environment. This system is now operational (in 1981).

A multiprogramming system for a microcomputer

AbstractA multiprogramming operating system nucleus has been constructed for a microcomputer. An account is given of the implementation, analysing the problems encountered, the magnitude of the effort required and the performance characteristics. The aim is to aid other implementors by drawing attention to those aspects of the work likely to be characteristic of microcomputer implementations in general.