A measurement-based analysis of the responsiveness of the Linux kernel

Abstract

Linux is not a real-time operating system, however it has been often recently used to implement soft real-time systems such as home multimedia centers. A quantitative study of the Linux kernel responsiveness to hardware interrupts has shown a huge variance in experimental results, however, we argue that a careful selection of the modules inserted in the kernel can greatly reduce this variance and produce a much more predictable system. In this paper, we focus on one of the major sources of unresponsiveness in the kernel, namely the presence of non-preemptible code sections, and we quantify its effects with a series of micro-benchmarks. Our extensive set of experiments allowed us to identify which Linux kernel's modules can cause erratic behavior with respect to the responsiveness of the Linux kernel to hardware interrupts