Enhancing the real-time capability of the Linux kernel

Linux has become one of the most popular UNIX operating systems. Commercial support for Linux and adoption of Linux in real world applications have now started to emerge. Some of the applications have strict real-time requirements. We discuss how to make Linux a real-time operating system. The real-time capability is achieved by three new kernel mechanisms. We port a microtimer into the kernel. We adopt the time-driven scheduling paradigm and implement a time-driven scheduler in the Linux kernel. Finally, we insert preemption points in the kernel to make it more preemptable so that real-time jobs may experience shorter blockings. Our approach is general and may be used to enhance the real-time capability of other non-real-time operating systems as well.