Real-Time scheduling and analysis of parallel tasks on heterogeneous multi-cores

Heterogeneous multi-cores and parallel architectures have recently gained much attention owing to utilizing the strength of different architectures for offering higher performance. In this paper, we study the real-time scheduling of the directed acyclic graph (DAG) tasks upon the heterogeneous multi-core platform, i.e., a task contains different types of vertices, and the workload of each vertex must execute on its particular type of cores. Traditional researches use the work-conserving scheduling strategy to schedule such a typed DAG task and lead to pessimistic schedulability tests. To this end, we propose a novel scheduling algorithm for typed DAG tasks, which assigns each vertex a varying criticality that depends on the remaining workload of the vertex, and moreover, the vertex with higher criticality is more urgent to be executed. Under this scheduling strategy, we propose a new worst-case response time (WCRT) bound to verify the schedulability of DAG task supporting heterogeneous computing. Experiments with randomly generated workload show that the accuracy of our new WCRT is about 20% higher on average than the existing bounds.