Linux实时抢占补丁研究及实时性能测试

Research of Linux Real-time Preemption Patch and Real-time Performance Measure

准确的量化数据可作为评测及选择实时Linux系统的参考依据。研究实时Linux系统中实时抢占补丁的关键特性,提出一种代码插桩的实时性能评测方法。在增加实时抢占补丁的Linux操作系统上加载运行测试程序,利用测试程序关键位置的代码探测段来获取运行系统中的重要信息,以完成实时性能的评测。对基于数控平台上该实时系统的中断响应时间和上下文切换时间等评测指标进行测试,结果表明,与标准Linux系统的评测指标相比,该系统的中断响应时间和上下文切换时间分别约减少10%和99%,达到了硬实时系统的要求,满足数控应用的实时需求。

To obtain accurate quantitative data as a reference for evaluating and selecting real-time Linux system,this paper researches several more critical characteristics of the real-time preemption patch of real-time Linux operating system in-depth,and proposes a method of program instrumentation for real-time performance evaluation. In the evaluating process,it loads and runs the test program on the Linux operating system with Preempt-RT patch, gets the important system information data by testing the key position of program with code probe to evaluate its real-time performance,and does the comparison test of the interrupt response time and context switch time as the most important criteria between Linux system with Preempt-RT patch and standard Linux system based on the numerical control system platform. Experimental result shows the interrupt response time on the patch system decreases by about 10% compared with standard Linux system,while context switch time decreases by about 99%,which satisfies the hard real-time system and meets the real-time demand of numerical control applications.