Issue No. 03 - March (1995 vol. 44)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/12.372041
<p><it>Abstract</it>—In many real-time systems relative timing constraints are imposed on a set of tasks. Generating a correct ordering for the tasks and deriving their proper start-time assignments is an NP-hard problem; it subsumes the Non-preemptive Scheduling Problem. Even when the application imposes a total order on the tasks, generating proper start-times is still nontrivial if execution times may range between upper and lower bounds.</p><p>We present the technique of <it>parametric dispatching</it> to enforce such timing constraints. During an off-line component, we check if the constraints can be guaranteed. If so, a calendar is produced that allows our on-line algorithm to generate upper and lower bounds on the start time of each task, based on the start times and execution times of previous tasks. A suitable start time for the task may then be selected taking into account the presence of other non-critical tasks in the system.</p>
Real-time, scheduling, dispatching, operating systems, linear constraints, variable elimination, programming languages.
M. Saksena, W. Pugh and R. Gerber, "Parametric Dispatching of Hard Real-Time Tasks," in IEEE Transactions on Computers, vol. 44, no. , pp. 471-479, 1995.