Jitter control in tiine-triggered systems

This paper addresses thejitter control issue in time-triggered real-time systems where tasks are activa.ted according to time. Our model is based on the dem.po-raldistance constrained task model (DCTS). However, many real-time systems hrave tasks that do not fit the simple assumptions of th,le DCTS model because tasks may occasionally access shared resources, and certain tasks may arrive irregularly. In this paper, We address the issues that cawe jitters in DCTS. We first review the algorithm developed for DCTS and present an extension for an optimal algorithm. Three jitter issues are then discussea!: sharing resources between tasks, handling tasks that have fixed and unchangeable periods, and handling ta.sks that arrive aperiodically. We present so1ution.s that can prevent jitters, as well as other solutions that may result in m.inor jitters.