嵌入式Linux2.6的实时性能研究与优化

Reasearch and Optimization on Real-Time Performance of Embedded Linux2.6 System

以Linux2.6内核为对象,对Linux系统实时性进行了研究.针对Linux中时钟粒度过大、临界区的执行造成系统反应延迟的不确定性和进程调度算法在任务调度过程中的公平性体现不够等,提出根据实时应用的特点设计了一个并行高精度定时器以提高时钟精度;采用自旋锁双模块控制方式对临界区进行管理以减少时延;修改0(1)调度算法的双队列操作,同时增加时间片轮询装置和采用动态计算通用进程的优先级和时间片的方法以提高调度的公平性和系统快速响应时间.实验测试表明:改进方案有效提高了系统的实时性,扩充了Linux在嵌入式领域的应用性.

The paper analyzes the real time performance of Linux2.6 kernel, because the key restrict factors which are clock, critical section and process scheduling, a new method called high-resolution timer is designed and implemented, spin-lock twin module-control method for critical section be adopted,and modify the 0（1） scheduling algorithm, all which are in order to improve the real-time performance of the Linux system efficiently. The test result indicates the improvements are successful to inprove the real-time performance of the Linux system, and the application range in embeded field is expanded.