Joint WCET and update activity minimization for cyber-physical systems

A cyber-physical system (CPS) is a desirable computing platform for many industrial and scientific applications, such as industrial process monitoring, environmental monitoring, chemical processes, and battlefield surveillance. The application of CPSs has two challenges: First, CPSs often include a number of sensor nodes. Update of preloaded code on remote sensor nodes powered by batteries is extremely energy consuming. The code update issue in the energy-sensitive CPS must be carefully considered. Second, CPSs are often real-time embedded systems with real-time properties.Worst-case execution time (WCET) is one of themost important metrics in real-time system design. Whereas existing works only consider one of these two challenges at a time, in this article, a compiler optimization-joint WCET and update-conscious compilation, or WUCC-is proposed to jointly consider WCET and code update for CPSs. The novelty of the proposed approach is that the WCET problem and code update problem are considered concurrently such that a balanced solution with minimal WCET and minimal code difference can be achieved. The experimental results show that the proposed technique can minimize WCET and code difference effectively.