Analysis of Overrun Strategies in Periodic Control Tasks
Abstract
The paper considers period overruns in control tasks with variations in execution time (or response time). A simple model is used, where the input and output operations are assumed to be time-triggered, and the execution-time distribution of the task is assumed to be known. Three overrun strategies, called Abort, Skip, and Queue, are modeled as discrete-time jump linear systems and are analyzed with regard to control performance. The analysis is exemplified on an integrator process. It is argued that the Skip strategy has good performance, is simple to analyze, and is easy to implement in real-time operating systems. Some simple extensions are also considered.
