Scenario-Based Meta-Scheduling for Power Performance Optimization Supporting Core and Router Frequency Scaling in Time-Triggered Multi-Core Architectures

Abstract:
Complex electronic systems are used in safety-critical applications (e.g., aerospace, nuclear stations), for which the certification standards demand the use of assured design methods and tools. Meta-scheduling is a way to manage the complexity of adaptive systems via predictable behavioural patterns established by static scheduling algorithms. This paper proposes a meta-scheduling algorithm for adaptive time-triggered systems based on Networks-on-a-Chip (NoCs). The meta-scheduling algorithm computes an individual schedule for each dynamic event of slack occurrence. Each dynamic slack occurrence triggers the shift to a more energy-efficient schedule. Dynamic frequency scaling of cores and routers is used to improve the energy efficiency, while preserving the temporal correctness of time-triggered computation and communication activities (e.g., collision avoidance, timeliness). Mixed-Integer Quadratic Programming (MIQP) is used to optimise the schedules Experimental results for an example scenario demonstrate that the presented meta-scheduling algorithm provides on average a power reduction of 34%. Our approach was able to deploy 93 dynamic slack schedules compared to the single slack schedule of using static slack scheduling.