Preemptive Scheduling with Release Times, Deadlines, and Due Times

Given n jobs, each of which has a release time, a deadline, and a processing requirement, the problem of determining whether there exists a preemptive schedule on m uniform machines which completes each job in the time interval between its release time and its deadline is examined. An o(m/sup 2/n/sup 4/+n/sup 5/) algorithm is presented which uses a generalisation of network flow techniques to construct such a schedule whenever one exists. This algorithm is then used with search techniques to find a schedule which minimises maximum lateness. 10 references.