Architecture and Real-Time Systems (ARTS) Laboratory

 Architecture and Real-Time Systems (ARTS) Laboratoryclock

Power Aware Fault-Tolerance

Real-time systems with space constraints have tight low-power requirements and must operate correctly in the presence of faults. This provides the motivation to explore the relationship between fault tolerance techniques and energy consumption. In particular, we established the energy efficiency of Application Level Fault Tolerance (ALFT) schemes over other software-based fault tolerance methods. In ALFT, task sets consist of primary and secondary tasks. Secondary tasks may be identical to the primary tasks or they can be a scaled down version of the primary tasks. We developed sensible energy-aware heuristics for ALFT schemes which either schedule the primary copies as early as possible or the secondary copies as late as possible. In the steady-state fault-free case, the heuristics decrease the need to run the secondary copies which result in up to 40% energy savings. Parts of this research appear in the 2002 International Symposium on Low Power Electronics and Design (ISLPED 2002)