Mixed-criticality system modelling with dynamic execution mode switching

In this paper, an executable system model for performing a functional simulation while observing the dynamic effects of mixed-criticality requirements regarding applications with different levels of assurance is proposed. The model provides the expression of dynamic execution modes and execution time estimates on each criticality level of the system. In a refinement step, it is possible to observe the effects of scheduling policies, dynamic criticality-, and execution mode switches on the functional behaviour of the system in a trace-based, simulative manner. An early evaluation of a quadrocopter platform consisting of a safety-critical flight control application and a video-based, performance-critical object detection is used to demonstrate the applicability of the design flow. Simulation results indicate that by defining multiple execution modes of the object detection algorithm, the run-time utilisation feedback allows the algorithm to run in a high-quality mode for more than 50% of the time, thereby increasing the overall system utilisation by two thirds compared to a static resource utilisation analysis.