Issue No. 05 - May (2009 vol. 58)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TC.2008.206
Jupyung Lee , Korea Advanced Institute of Science and Technology, Daejeon
Kyu Ho Park , Korea Advanced Institute of Science and Technology, Daejeon
In this paper, we propose a novel scheduling technique to improve the responsiveness of a real-time process while maintaining relative execution rates of non-real-time processes, called the prediction-based micro-scheduler. It runs upon an existing macro-scheduler and it conditionally rearranges the scheduling pattern generated by the macro-scheduler based on urgent interval prediction and lock hold time prediction. The rearrangement occurs if one process seeks to enter a long nonpreemptible section and the operation is predicted to significantly disturb the future execution of a real-time process. We implemented the prototype on Linux 2.6.19. Experimental results show that the average OS latency of a real-time process is reduced up to 34 percent of the original one while still maintaining relative execution rates of non-real-time processes. Moreover, the performance degradation caused by the micro-scheduler does not exceed 5 percent.
Real-time operating system, Linux, scheduling, OS latency, kernel preemptibility, interrupt.
J. Lee and K. H. Park, "Prediction-Based Micro-Scheduler: Toward Responsive Scheduling of General-Purpose Operating Systems," in IEEE Transactions on Computers, vol. 58, no. , pp. 648-661, 2008.