Any processor is said to be optimally performing if it has a higher throughput, low waiting time, low turn around time, and less number of context switches for the processes coming for execution. The scheduler is the component which is responsible for taking the decision on how and when to schedule the processes waiting in the ready queue for their chance to get the CPU. In this paper we have given a proposal for modifying the classical round robin scheduling algorithm. The proposal works by finding the left out burst time of the processes in the last but one turns of the quantum cycle. The left out burst time values in last but one turn of each process are processed to get an optimal threshold value. Based on this, we have divided the processes waiting in the ready queue in two categories. The processes in the first category are the one for which we will modify the time quantum and the processes in the second category will be processed as per the classical round robin algorithm. We have also compared our proposal with the classical round robin algorithm and the results are depicted in tabular form.

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Scheduling Turn Around Time Context Switches Waiting Time