https://wiki.bu.ost.ch/infoportal/ 2026-05-16T16:31:01+00:00 https://wiki.bu.ost.ch/infoportal/ https://wiki.bu.ost.ch/infoportal/lib/tpl/ntb2/images/favicon.ico text/html 2023-04-11T11:19:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.bu.ost.ch/infoportal/software/linux/realtime/benchmark?rev=1681204789&do=diff Benchmark Introduction There are many different tools available to measure the realtime performance of a system. The cyclictest is the simplest and most usefull benchmark. Tools Cyclictest Standard tool to measure the maximum jitter of a system. text/html 2023-04-11T10:57:09+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.bu.ost.ch/infoportal/software/linux/realtime/build_kernel?rev=1681203429&do=diff Building a Preemt-RT Kernel Introduction The kernel can be easily installed on a running system. During the boot process, the kernel is started with the latest version number by default. If you want to return to an old version, you can select the desired kernel version in the grub menu text/html 2023-04-11T11:07:02+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.bu.ost.ch/infoportal/software/linux/realtime/cyclictest?rev=1681204022&do=diff Cyclictest The Cyclictest starts several tasks, which are called periodically. The effective period duration is measured and the jitter is displayed. * Cyclictest website A presentation from the „Embedded Linux Conference 2013“ offers a good introduction to the use of Cyclictest. The presentation can be watched on text/html 2023-04-18T14:38:42+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.bu.ost.ch/infoportal/software/linux/realtime/preempt_rt?rev=1681821522&do=diff Preempt-RT Linux Preempt_RT [Preempt_RT] Projekt webseite Introduction Preempt_RT is a patch for the Linux kernel maintained by Ingo Molnar. It modifies the kernel so that it becomes (almost) completely preemptive. The classic kernel spinlocks are replaced by mutexes which support priority inheritance. In addition, the handling of all interrupts is outsourced to separate kernel threads. The presentation text/html 2023-04-11T11:21:54+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.bu.ost.ch/infoportal/software/linux/realtime/start?rev=1681204914&do=diff Realtime * PreemtRT * Build Preempt-RT Kernel * Tune BIOS Settings * Benchmark * Cyclictest * Tested Devices * Stress Tests text/html 2023-04-11T09:40:50+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.bu.ost.ch/infoportal/software/linux/realtime/stresstests?rev=1681198850&do=diff Künstliche Belastungen für ein RT-System Einleitung dd ist eine einfache Möglichkeit die CPU auszulasten. Es wird nur die Komandozeile und keine zusätzliche Software benötigt. stress ist eine Software, die die CPU gründlicher auslastet als dd text/html 2023-04-11T09:53:58+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.bu.ost.ch/infoportal/software/linux/realtime/testeddevices?rev=1681199638&do=diff Tested Devices Introduction The maximum jitter of a device roughly describes how well real-time requirements can be met.. If a device has a maximum jitter of 100us, then it must be expected that an event is handled up to 100us too late. Tips Use: text/html 2019-02-15T11:10:43+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.bu.ost.ch/infoportal/software/linux/realtime/tune_bios_settings?rev=1550225443&do=diff Tune BIOS Settings In order to achieve the best possible real-time performance, some options can be set in the BIOS menu. The options below are taken from a BIOS on a Dell machine. Computers from other manufacturers may contain similar options. Which options are ideal depends on the system. It is normally