CS 471: Operating System Concepts

• mémoire
• cours magistral

CS-471 OPERATING SYSTEM CONCEPTS HW2 - 1 - CS 471: Operating System Concepts Spring 2009 Lecture: T 1910-2150 HW _1 Points: 20 Due: Jan 27, 2009 Question 1 [Points 10] Exercise 5.12 using the following data (with RR Quantum = 4 instead of 1 as in the textbook) Process Arrival time Burst time Priority P1 10 10 2 P2 15 4 1 P3 20 12 4 P4 5 8 3 P5 25 6 5 Solution: FCFS: 0-5 Idle 5-13 P4 13-23 P1 23-27 P2 27-39 P3 39-45 P5 Turnaround time = Process finish time – Arrival time Waiting time = Turnaround

• cpu
• finish time turnaround time
• burst time
• io1
• 22.6-22.8 cs 22.8-23.8 io3 23.8-24.0 cs 24.0-25.0 io4 25.0-25.2 cs
• 45.4 45.4 35.4 io3 49.4 49.4 39.4 io4
• cs
• 3 cs
• 2 cs
• idle 37.4-37.6 cs