Summary: IEEE Real­Time and Embedded Technology and Applications Symposium (RTAS),San Jose, California, 2002 1
A Measurement­Based Analysis of the Real­Time Performance of Linux 
Luca Abeni y , Ashvin Goel, Charles Krasic, Jim Snow, Jonathan Walpole
luca@sssup.it, fashvin, krasic, jsnow, walpoleg@cse.ogi.edu
Department of Computer Science and Engineering
Oregon Graduate Institute, Portland
Abstract
This paper presents an experimental study of the latency
behavior of the Linux OS. We identify major sources of la­
tency in the kernel with the goal of providing real­time per­
formance in a widely used general­purpose operating sys­
tem. We quantify each source of latency with a series of
micro­benchmarks and also evaluate the effects of latency
on a time­sensitive application. Our analysis shows that
there are two main causes of latency in the OS: timer res­
olution and non­preemptable sections. Our experiments
show that in the standard Linux kernel the timer resolu­
tion latency is predominant, and generally hides the non­
preemptable section latency. We use accurate timers to
reduce timer resolution latency and then analyze the non­

Source: Abeni, Luca - Dipartimento di Ingegneria e Scienza dell'Informazione, Università di Trento

Collections: Computer Technologies and Information Sciences