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Unformatted text preview: (or you have failed to meet your deadline). In real-time systems, the load must stay < 1 or tasks will not complete in time. Rate monotonic Pre-emption is allowed. Without pre-emption, it is possible for task deadlines not to be met because one process might hold the processor causing another job not to complete in time Rate monotonic scheduling relies on the following assumptions: 1. Tasks are periodic and T i is the period for task t i 2. Tasks do not communicate with each other 3. Tasks are scheduled according to priority, and task priorities are fixed (static priority scheduling) (C i , T i ) => (CPU time, period) Then 3 tasks (1,4) (3,9) and (1,2) then priorities from highest to lowest are (1,2), (1,4), (3,9) 1) Given a set of tasks how do we determine if the jobs can be run in a feasible manner? 2) Is this optimal? Is the scheme cannot be scheduled, is there another algorithm that can be used to schedule the tasks?...
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- Fall '08
- Operating Systems, Greedy algorithm, Central processing unit, Computer multitasking, Real-time computing, Real-time operating system, Earliest deadline first scheduling