Proportional Weighted Round Robin: A Proportional Share CPU Scheduler inTime Sharing Systems

Abstract

In time sharing systems, many processes reside in the ready queue and compete for execution by the processor. Therefore, scheduling these processes on CPU as it can run only one process at a time is needed. In this paper, a modified version of RoundRobin (RR) called proportional weighted round robin (PWRR) is proposed. The proposed scheduler is a proportional share scheduler designed explicitly for time sharing systems. The proposed scheduler improves some scheduling criteria by minimizing turnaround times, waiting times, and context switches for the running processes. A threshold is considered to determine whether the system cannot take away the CPU from the process until it finishes or the process is interrupted due to the expiration of its time slice assigned by the RR policy. According to evaluation results, the proposed scheduler minimizes some scheduling criteria (turnaround times, waiting times, and context switches in this context)..