Research And Improvement Of Real-Time Operating System μC/OS-II Task Scheduling Mechanism

The real-time operating system widely applies in the field of communication and information, playing the vital role. The well-known real-time operating system has VxWorks, WinCE,μClinux,μC/OS-II and so on. The paper choosesμC/OS-II to take the object of study is because its source code is public and its kernel is small.μC/OS-II as a priority-based preemptive kernel,its task scheduling algorithm efficiency is high and the task cuts quickly. But the real-time operating systemμC/OS-II also has some insufficiencies: the priority of any task can not be same; the tasks that need to run simultaneously can only be achieved through the task synchronization, increasing the complexity of program development.In this paper, it makes the improvement to operating system's task scheduling based on the insufficiency stated above. After the improvement, the operating systemμC/OS-II can create the same priority task. Tasks with the same priority use the time piece rotation scheduling, and tasks with different priority still used priority-based preemptive scheduling. In this paper, it first studiesμC/OS-II operating system's architecture, especially the task scheduling mechanism, then solves the question needing to be solved when the time piece rotation scheduling is added, and then realizes the time piece rotation scheduling strategy of the same priority task, as well as the related function. Finally the paper analyses and validates the result after improving.