A Grouped HalfLife Quantum Time Round Robin Scheduling

A Grouped Half-Life Quantum Time Round Robin Scheduling (GHLVQTRR) Algorithm for CPU Process YUSUF Salisu Ibrahim, S E Abdullahi Ph. D Computer Science Department, BAZE University, Nigeria. Computer Science Department, Nile University of Nigeria, Nigeria. 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

Operating System and CPU process Scheduling • Intermediary between the computer resources and computer users. • CPU is the most scarce computer resource. • CPU Scheduling algorithms are used to coordinate the processing activities. 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

CPU Scheduling Algorithms 1. First-In-First-Out (FIFO)/First-Come-First-Serve (FCFS). 2. Shortest-Job-First (SJF). 3. Longest-Job-First (LJF). 4. Priority Based Scheduling. 5. Round Robin (RR). 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

Evaluation Criteria • CPU Utilization. • Throughput. • Turnaround Time. • Waiting Time. • Response Time. • Context Switching. 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

Round Robin Algorithm • Processes take turns based of a TIME SLICE aka QUANTUM TIME. Traditionally uses the average of the processes burst times. • Very effective in a multiprogramming environment. Challenges in determining QT • Small QT large context switching. • Large QT system behaves like FCFS 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

Variations Round Robin Algorithm • Dynamic Round Robin with controlled pre-emption (DRRCP) (Ashiru, et al. , 2014). • Priority based Round Robin CPU scheduling algorithms for real time system (Singh & Deepa, 2012). • Variable Quantum Time (VQT) algorithm which is based on averaging technique (Yashasvini, 2013). • In Even Odd Round Robin (EORR), there are two QT (QT 1 and QT 2). • … 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

Variations Round Robin Algorithm • Average Mid Max Round Robin (AMMRR), • Ascending Quantum Minimum and Maximum Round Robin (AQMMRR). (Dawood, 2012). • The Half Life Variable Quantum Time Round Robin (HLVQTRR) (Ashiru, et al. , 2014). ▫ Takes ½ of the individual burst time of process as QT for the process. ▫ Limitation observed: relatively very large processes will spent very long time executing 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

A Grouped HLVQTRR • An optimization of HLVQTRR • Recursively grouped group processes based on their burst times. • ½ of the average of the processes is made to be the QT of process less than or equal to the half of the average. 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

Comparing G-HLVQTRR and HLVQTRR Case 1: 7 processes, range: 84 – 93 average: 88 Criteria HLVQTRR G-HLVQTRR Average Waiting Time 398. 29 398. 86 Number of context Switching. 7 7 Average Turn Around Time 486. 71 487. 29 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

Comparing G-HLVQTRR and HLVQTRR Case 2: 20 processes, range: 3 – 21 average: 9. 4 Criteria HLVQTRR G-HLVQTRR Average Waiting Time 127. 33 108. 15 Number of context Switching. 20 15 Average Turn Around Time 133. 53 127 3 rd Big Data Analytics and Innovation Conference, 22 -25 November, NDC, Abuja, Nigeria

Discussion • When the range of the process difference is wide. HLVQTRR algorithm was slight better • With a wider range the proposed algorithm much better

Other Applications of Scheduling algorithm. • Parallel computing: task sharing. • Military: Optimal use of scarce resource. • Personal: time management.