OpenIoT & ELC Europe 2016

Linux became the fastest growing platform in the embedded sector. One reason for this success is the huge number of supported hardware platforms. In addition it became very easy to get hard realtime capabilities to Linux. The PREEMPT_RT patch became the de-facto standard for Linux and realtime. It is available for every second kernel release and will be included in the mainline kernel in the near future. This talk gives an overview of the history of realtime Linux, the different approaches and the advantages of the PREEMPT_RT patch in comparison to other approaches. Furthermore it shows the latency results on a modern Cortex A9 platform for PREEMPT_RT and Xenomai (a so called dual-kernel approach). These measurements prove, that PREEMPT_RT is much easier to use and it can achieve latencies which are comparable to the latencies of dual kernel approaches like Xenomai or RTAI.