Partitioned Schemes And Implementation On Multi-Core Mixed-criticality Real-time Systems

With the development of science and information technology, the multi-core hybrid critical real-time system is widely used in the design and implementation of embedded system, such as automotive electronic systems and aerospace electronic systems. How to make the system to ensure that higher safety and reliability and ensure real-time will be of mixed criticality real-time system is an indispensable issue.Based on the test method proposed by Baruah, the division strategy BF and WF are improved, and the new partition strategy WF_NEW and BF_NEW is obtained. The traditional partition strategy is only suitable for the execution time of a task, and the scheduling of the mixed criticality tasks is not adaptive. But the improved partition strategy is based on the all key level execution time utilization of mixed criticality tasks, so the improved partition strategy improves the schedulability of tasks in largely. According to the idea of WF, the division strategy WF_MY is designed, and the main idea of this division strategy is to reserve a larger processor space for the next task. Therefore, it has the predictability, increases the accuracy of the task partitioning, and improves the schedulability of the task set.By modifying the kernel, the hybrid criticality scheduling algorithm MC-P-EDF is realized, and the partition strategy FF, BF, WF, WF_NEW, BF_NEW, HYBRID and WF_MY are implemented respectively. By comparing the scheduling rates under the different mutation rate in each partition strategy, it is found that the partition algorithm improves the task set schedulability rate to a large extent, especially in BF_NEW partition strategy. And through the analysis of the graph of the task preemption with the change rate under the fixed processor utilization, the higher the variation rate is, the less the preemption number is.