1. A non-preemptive scheduling problem

2. Non-preemptive scheduling qA job: (a, e, d) arrives at instant a deadline at instant d must execute non-preemptively for e time units qSet of such jobs: {(a 1, e 1, d 1 ), (a 2, e 2, d 2 ),...,(a n, e n, d n )} –feasible? NP-C in the SSis NP-C in the SS (transform from 3-partition) qSet of such jobs + a deteministic scheduling algorithm (deterministic sch alg: e.g., EDF + ties broken by job-ID) –feasible? polynomial-time for reasonable algs (simulate the algorithm)

3. Robust Robust Non-preemptive scheduling (thanks, Al) qA job: (a, e, d) arrives at instant a deadline at instant d must execute non-preemptively for at most e time units qSet of such jobs: {(a 1, e 1, d 1 ), (a 2, e 2, d 2 ),...,(a n, e n, d n )} –robust feasible -- feasible for any set of execution requirements satisfying [e 1 ’  e 1, e 2 ’  e 2,..., e n ’  e n ] –robust feasibility is also NP-C in the SS qSet of such jobs + a deteministic scheduling algorithm –an algorithm for robust feasibility?

4. Problem Statement Given a system of non-preemptable jobs {(a 1, e 1, d 1 ), (a 2, e 2, d 2 ),...,(a n, e n, d n )} determine whether this system of jobs is robust- feasible when scheduled using EDF with ties broken by job-index