Development of scheduling algorithms is directly related with the development of operating system which brings difficulties in implementation. Any modification on the scheduling algorithm will appear as modification on the operating system kernel code. Processor is an important source of cpu scheduling process, so it becomes very important on accomplishing of the operating system design goals. A delicate problem of the well-functioning of SO is the case when in CPU comes two or more processes which wants to be executed. Scheduling includes a range of mechanisms and policies that SO has to follows in order that all processes take the service. In this Paper we will discuss about two main batches algorithms, such as FCFS and SJF, and i will show a manner how to improve these algorithms in the future work.

 

Published In : IJCSN Journal Volume 3, Issue 6

Date of Publication : December 2014

Pages : 444 - 449

Figures : 08

Tables : 02

Publication Link : Simulation of First Come First Served (FCFS) and Shortest Job First (SJF) Algorithms

 

 

 

Nevila Xoxa : University of Tirana, Faculty of Natural Science

Marjo Zotaj : Polytechnic University of Tirana, Faculty of Information and Technology

Igli Tafa : Polytechnic University of Tirana, Faculty of Information and Technology

Julian Fejzaj : University of Tirana, Faculty of Natural Science

 

 

 

 

 

 

 

CPU-Scheduling

Scheduler

FCFS

SJF

After execution of simulation codes of FCFS and SJF I come to the conclusion that SJF algorithm is more competitive than FCFS If we talk about performance because It has minimal average waiting that is very important.SJF main flaw is : a very long process to be not executed at the time required, thing that does not happen to FCFS algorithm.

 

 

 

 

 

 

 

 

 

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