22 06 2023 E TS

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Advanced Operating Systems - Part A, June 22nd, 2023 Exercises and solutions Exam finalization Question 1.1 This is part A of the AOS’s exam and today you are finalising your entire grade. You must express now how you have finalised part B. The answer is mandatory for the entire exam. Exercise 2 — Open and closed questions (Points 15) Question 2.1 (Points 5) Describe the following concepts related to concurrency in the Linux kernel. Please USE CAPITAL LETTERS and respect the space allocated to each class. Solution Question 2.2 (Points 5) Describe the following concepts related to IO management in linux. Please USE CAPITAL LETTERS and respect the space allocated to each concept. Question 2.3 (Points 3) Describe a reader/writer lock by using pseudocode for the readers’ and writers’ locking and unlocking operations. Solution Question 2.4 (Points 2) Describe the Linux load balancing scheduler in the context of a NUMA machine. Solution Exercise 3 — Scheduling (Points 7) Question 3.1 (Points 7) Given the following task set: Task Arrival time ( Ai) Computation time ( Ci) T0 3 5 T1 2 4 T2 6 5 T3 2 8 1. Draw the Gantt diagram of the schedule obtained by applying the Highest Response Ratio Next. In case of tasks with the same ratio value, pick from the queue the one with the shortest computation time. 2. Compute the turnaround time Z and waiting time W for each task i in the schedule and then the average values of those. Solution Exercise 3 Given the following task set, you are asked to draw the Gantt diagram of the schedule obtained by applying the Highest Response Ratio Next (HRRN) algorithm. In case of tasks with the same ratio value, pick from the queue the one with the shortest computation time. Task Arrival time Computation time 0 3 5 1 2 4 2 6 5 3 2 8 0 xxxxx 1 xxxx 2…