On-line scheduling of real-time tasks

Abstract

The problem of online scheduling of a set of n independent, real-time tasks on m>or=1 identical processors is addressed. An online scheduler is said to be optimal if it performs as well as the best offline scheduler. It is shown that no optimal online scheduler can exist if the tasks have more than one distinct deadline. An optimal online scheduler for tasks with one common deadline is given. An optimal online scheduler is also given for environments in which processors can go down unexpectedly.<>