• International Journal of Computer Science & Network Security
• /
• v.23 no.7
• /
• pp.165-170
• /
• 2023

Scheduling algorithms plays a significant role in optimizing the CPU in operating system. Each scheduling algorithms schedules the processes in the ready queue with its own algorithm design and its properties. In this paper, the performance analysis of First come First serve scheduling, Non preemptive scheduling, Preemptive scheduling, Shortest Job scheduling and Round Robin algorithm has been discussed with an example and the results has been analyzed with the performance parameters such as minimum waiting time, minimum turnaround time and Response time.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.9
• /
• pp.2213-2221
• /
• 2015

The ondemand governor used in android-based smartphone platforms is a CPU frequency scaling technique. The ondemand governor sets the CPU operating frequency depending on the CPU utilization rate. Job scheduling affects the CPU utilization rate. The power consumption is proportional to the value of operating frequency. Consequently, CPU frequency scaling and CPU utilization rate have an effect on power consumption in a smartphone. In this paper, we evaluated the performance of job scheduling techniques incorporating the ondemand governor in terms of CPU utilization, power consumption, and job deadline miss ratio.

• International Journal of Computer Science & Network Security
• /
• v.21 no.1
• /
• pp.19-26
• /
• 2021

CPU is considered the main and most important resource in the computer system. The CPU scheduling is defined as a procedure that determines which process will enter the CPU to be executed, and another process will be waiting for its turn to be performed. CPU management scheduling algorithms are the major service in the operating systems that fulfill the maximum utilization of the CPU. This article aims to review the studies on the CPU scheduling algorithms towards comparing which is the best algorithm. After we conducted a review of the Round Robin, Shortest Job First, First Come First Served, and Priority algorithms, we found that several researchers have suggested various ways to improve CPU optimization criteria through different algorithms to improve the waiting time, response time, and turnaround time but there is no algorithm is better in all criteria.

• Journal of Information Processing Systems
• /
• v.13 no.4
• /
• pp.941-950
• /
• 2017

The round robin algorithm is regarded as one of the most efficient and effective CPU scheduling techniques in computing. It centres on the processing time required for a CPU to execute available jobs. Although there are other CPU scheduling algorithms based on processing time which use different criteria, the round robin algorithm has gained much popularity due to its optimal time-shared environment. The effectiveness of this algorithm depends strongly on the choice of time quantum. This paper presents a new effective round robin CPU scheduling algorithm. The effectiveness here lies in the fact that the proposed algorithm depends on a dynamically allocated time quantum in each round. Its performance is compared with both traditional and enhanced round robin algorithms, and the findings demonstrate an improved performance in terms of average waiting time, average turnaround time and context switching.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.4
• /
• pp.835-842
• /
• 2012

Operating Systems is a discipline which handles abstract concepts and techniques. However, most of OS courses have been textbook-oriented theoretical classes. Theoretical classes lead to the decline in the understanding of a lecture, and hurt their concentration. Many instructors have tried to make use of educational tools to help students understand lectures and arouse interests. This paper describes the design and implementation of a CPU scheduling simulator which shows the operation of process scheduling algorithms visually. The academic achievement evaluation for 2010's students and 2011's and t-test results show that the differences of the correct answer ratio for the exam about CPU scheduling algorithms are meaningful. The survey shows that the simulator is useful as an educational tool which causes the interests and enhances the understanding of a lecture, this teaching method is effective to develop problem solving skills.

• Journal of Korea Multimedia Society
• /
• v.14 no.3
• /
• pp.449-461
• /
• 2011

In the field of computer science, operating system concept is taught in university, but we now teach it in the middle and/or high school. Computer is also taught not only in college but also in middle and high school. If we look up the education of computer that is trained in school, basic principles or core techniques of computer science is educated only with its theory. If the theoretical education of computer science is just trained, sometimes students are not interested in it because of lack of shortage of mass media. Therefore, we could say that it is important that the computer education features a diverse range of media, including prints, paintings, sculpture, digital photographs, mixed media, and a simulation program. For all this reason, we design and implement a program for simulation with computer operating systems especially, CPU scheduling. There are many CPU scheduling algorithms we suggest to make students understand scheduling with some different examples in practical use. In this paper, we practically propose a new approach to be used with a study tool to make a motivation for students. We design a simulation program for teaching computer operation systems to show CPU scheduling and we implement a program to make use of comparison of FCFS, SJFS, PS, and RR scheduling algorithms. With our simulation program we present a comparative analysis between scheduling algorithms could be possible.

• Journal of Digital Convergence
• /
• v.12 no.3
• /
• pp.227-235
• /
• 2014

Mobile virtualization is an approach to mobile device management in which two virtual platforms are installed on a single wireless device. A smartphone, a single wireless device, might have one virtual environment for business use and one for personal use. Mobile virtualization might also allow one device to run two different operating systems, allowing the same phone to run both RTOS and Android apps. In this paper, we propose the techniques to virtualize the cores of a multicore, allowing the reassign any number of vCPUs that are exposed to a OS to any subset of the pCPUs. And then we also propose the real-time scheduling method to assigning the vCPUs to the pCPU. Suggested technology in this paper solves problem that increases time of real-time process when interrupt are handled, and is able more to fast processing than previous algorithm.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.7
• /
• pp.1653-1659
• /
• 2015

Operating Systems is a discipline which handles abstract concepts and techniques. However, most of OS courses have been textbook-oriented theoretical classes. Theoretical classes lead to the decline in the understanding of a lecture and hurt their concentration. Many instructors have tried various ways to help students understand lectures and arouse interests. This paper describes the design and implementation of a web-based educational CPU scheduling simulator which enables learners to set up various situations and simulate scheduling processes using a web browser or a smart-phone. After utilizing the implemented simulator for the class, the survey result for 2014's students shows that it is useful as an educational tool which enhances the understanding of a lecture and develops their problem solving skills.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.10
• /
• pp.1432-1440
• /
• 2022

Recently, as Virtual Desktop Infrastructure(VDI) is widely used not only in office work environments but also in workloads that use high-spec multi-core-based applications, the requirements for real-time and stability of VDI are increasing. Accordingly, the display protocol used for remote access in VDI and performance optimization of virtual machines have also become more important. In this paper, we propose two ways to configure desktop virtualization for multi-core-based application operation. First, we propose a codec configuration of a display protocol with optimal performance in a high load situation due to multi-processing. Second, we propose a virtual CPU scheduling optimization method to reduce scheduling delay in case of CPU contention between virtual machines. As a result of the test, it was confirmed that the H.264 codec of Blast Extreme showed the best and stable frame, and the scheduling performance of the virtual CPU was improved through scheduling optimization.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.16 no.5
• /
• pp.575-580
• /
• 2006

It is important matter that inflect well allocated frequency resource in cellular network and is still more serious element in environment that provide multimedia services. This paper describes model and algorithm that increase two elements that is frequency allocation and job scheduling that consider multimedia service traffic special quality by emphasis that do mapping present in CDMA cellular system. We proposed the model composed three parts (channel allocation algorithm, mapping algorithm and scheduling algorithm) and simulation results.