Priority-Based Scheduling
Priority-Based Scheduling
Define scheduling and scheduler.
Differentiate static and dynamic priorities.
Explain Rate Monotonic Scheduling (RMS).
Explain Earliest Deadline First (EDF).
Calculate task priorities.
Perform basic schedulability analysis.
Compare RMS and EDF advantages.
Priority-Based Scheduling: For the set of periodic processes P1 (Execution Time = 1, Period = 3), P2 (Execution Time = 1, Period = 4), P3 (Execution Time = 2, Period = 6): (a) Schedule the processes using the Rate Monotonic Scheduling (RMS) algorithm over a time interval equal to the Least Common Multiple (LCM) of their periods. Assign priorities according to RMS policy, compute CPU utilization and perform the bound test. (b) Schedule the same task set using the Least Slack Time (LST) algorithm and construct the schedule until the slack time of any process becomes zero.
A smart phone service centre receives service requests represented by periodic real-time tasks: A(Period=3, Execution Time=1), B(5,1), C(6,1), D(8,2), E(10,1). Construct schedules using Rate Monotonic Scheduling (RMS) and Earliest Deadline First (EDF). Compare the resulting schedules to analyse which algorithm utilizes the CPU more efficiently. Assume all tasks arrive at time 0 and each deadline equals its period.
A car manufacturing industry has Task 1 (Execution Time = 2 s, Period = 4 s), Task 2 (Execution Time = 3 s, Period = 8 s), and Task 3 (Execution Time = 4 s, Period = 24 s). Assume all tasks arrive at time 0. Schedule the tasks using any two scheduling models and analyse CPU utilization and constraints with a timeline graph.
Using two sample datasets of your choice, demonstrate one case where Rate Monotonic Scheduling (RMS) fails and another where it succeeds. Identify the causes of scheduling success and failure, and provide suitable remedies with proper justification.
Using the dataset T1(Execution Time=5, Period=15), T2(Execution Time=7, Period=10), T3(Execution Time=10, Period=20), show that RMS creates a feasible schedule. If the execution times do not allow a feasible schedule, modify them appropriately, perform RMS scheduling again, and draw the task timeline graph for at least three cycles.
List any five Hard and Soft Real-Time Systems. Compare RMS and EDF. Schedule the following task set using RMS: P1(Period=3, Execution Time=1), P2(Period=5, Execution Time=3), P3(Period=6, Execution Time=1).
Compare RMS and EDF. Schedule the following task set using both RMS and EDF: P1(Period=4, Execution Time=1), P2(Period=6, Execution Time=3), P3(Period=5, Execution Time=1).