Evaluation of Low Latency Kernel of Linux for Periodic Control

Abstract

It is difficult that to accurately run periodic process in cycle of less than a few tens of millisecond, using normal Linux distributions with normal scheduling policy in round-robin fashion. This article shows an easy way to resolve the problem by replacing the kernel with a low latency kernel. Its performance of latency without intentional load was evaluated using a frequently-used command at various interval and priority. It is possible that to design original software which runs on the soft-realtime OS. To evaluate its usability, we demonstrated positional control of a manipulator every 5 milliseconds. By running the control software on CUI environment, standard deviation of the time interval was suppressed compared to running the same software on GUI environment.