hw04(1)

hw04(1) - 300ms. Task Round 1 Round 2 Arrival Run Activity...

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EE 4770 Homework 4 Due: 24 April 1998 Problem 1: The table below describes tasks on an otherwise empty processor. Show the CPU activity and the task states from time zero until tasks E and F finish or until task B first runs, whichever is later. Assume that the scheduler is called at t =0 . The system uses a two-level scheduler. The first round uses round-robin scheduling with class sequence { α, β, γ, β } ,c la s s α will be chosen at time zero. (Note that β appears twice in the class sequence so class β tasks get twice as many opportunities to run.) Class α tasks are chosen using a priority scheme, class β are chosen using deadline scheduling, and γ are chosen using first
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Unformatted text preview: 300ms. Task Round 1 Round 2 Arrival Run Activity Name Class Info Time Time A α Prio 2 0ms ∞ Repeats: 15ms, wait until multp of 100ms. B α Prio 1 0ms 200ms C β 235ms deadline 215ms 10ms D β 265ms deadline 205ms 30ms E γ FCFS 5ms 70ms F γ FCFS 10ms 90ms Problem 2: The scheduling used above does not guarantee that deadline-scheduled tasks will run as soon as they arrive. Modify the scheduling so that tasks C and D will not have to wait for any of the others, while maintaining the round-robin relationship between tasks in classes α and γ , and the priority and FCFS used within those classes. Problem 3: Compute the worst-case latency and response time for the one-shot events listed in the table below. Event Strong Weak Handler Name Prior. Prior. Run Time A 2 2 2 μ s B 2 1 3 μ s C 1 3 4 μ s D 1 2 5 μ s E 1 1 100 μ s...
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This note was uploaded on 11/28/2011 for the course EE 4770 taught by Professor Staff during the Fall '99 term at LSU.

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