Abstract
Clock precision directly affects that if tasks can be timely responded and scheduled or not. As a time-sharing system, Linux cyclical time granularity can not achieve microsecond response precision. Simply raising clock frequency means that the clock interrupt's process will take up too much time of processor. And it makes the system's effective utilization decline. This paper introduces some ways of improving clock's precision for real-time Linux, analyses the theory of MontaVista Linux high resolution timer (HRT) mechanism, implements a high-precision clock in current popular embedded operating systems through modifying Linux kernel to design a Linux high-precision timer to raising the Linux clock precision effectively.