PREEMPTIVE SCHEDULING ON PARALLEL PROCESSORS WITH DUE DATES

Preemptive Scheduling with Variable Profile, Precedence Constraints and Due Dates

This paper is concerned with the problem of scheduling preemptive tasks subject to precedence constraints in order to minimize the maximum lateness and the makespan. The number of available parallel processors is allowed to vary in time. It is shown that when an Earliest Due Date rst algorithm provides an optimal nonpreemptive schedule for unit-execution-time (UET) tasks, then the preemptive pr...

Integer preemptive scheduling on parallel machines

We consider preemptive machine scheduling problems on identical parallel machines. It is shown that every such problem with chain-like precedence constraints, release dates and a regular unit-concave objective function has the following integer preemption property : for any problem instance with integral input data there exists an optimal schedule where all interruptions (as well as starting an...

Online Preemptive Scheduling on Parallel Machines

We consider an online version of the classical problem of preemptive scheduling on uniformly related machines. We are given m machines with speeds s 1 ≥ s 2 ≥. .. ≥ s m and a sequence of jobs, each described by its processing time (length). The actual time needed to process a job with length p on a machine with speed s is p/s. In the preemptive version, each job may be divided into several piec...

Preemptive on-line scheduling for two uniform processors

This paper considers the problem of preemptive on-line scheduling for two uniform processors in which one of the processors has speed 1 and the other has speed s¿1. The objective is to minimize the makespan. A best possible algorithm with competitive ratio of (1+s)=(1+s+s) is proposed for this problem. c © 1998 Elsevier Science B.V. All rights reserved.

Preemptive Scheduling on Dedicated Processors: Applications of Fractional Graph Coloring