分析了 Linux 的實時性，針對其在實時應用中的技術障礙，在參考了與此相關研究基礎上，從三方面提出了改善Linux 實時性能的改進措施。為提高嵌入式應用響應時間精度,提出兩種細化Linux 時鐘粒度方法；為增強系統內核對實時任務的響應能力,采用插入搶占點和修改內核法增強Linux 內核的可搶占性；為保證硬實時任務的時限要求，把原Linux 的單運行隊列改為雙運行隊列,硬實時任務單獨被放在一個隊列中,并采用MLF 調度算法代替原內核的FIFO 調度算法。
關鍵詞：Linux；實時性；調度策略；搶占
Abstract: The real-time performance of Linux is analyzed, and its disadvantage is pointed out when applied to the embedded system. Inspired mostly by some real time improvements of Linux, this article gives rise to three aspects to improve the real-time capability of Linux. To improve the time precision for embedded applications, two methods for creating accurate timer are proposed. To enhance the response ability of real-time task, inserting preemption points and the preemption kernel methods are adopted to enhance the preemptability of Linux kernel. To ensure the requirements of the hard real-time tasks, a double run queue is used instead of the original single run queue, these tasks are organized in one run queue and MLF schedule strategy is used for them.
Key word: Linux；Real-time；Schedule strategy；Preemption