[bootlin/training-materials updates] master: Real-time lab: explain why we're testing with load first before using chrt (cf984e37)

Thomas Petazzoni thomas.petazzoni at bootlin.com
Fri Oct 29 10:46:38 CEST 2021

Repository : https://github.com/bootlin/training-materials
On branch  : master
Link       : https://github.com/bootlin/training-materials/commit/cf984e37b5ce5ae4acd19abfb8143c292590ae5c


commit cf984e37b5ce5ae4acd19abfb8143c292590ae5c
Author: Michael Opdenacker <michael.opdenacker at bootlin.com>
Date:   Fri May 21 10:13:23 2021 +0200

    Real-time lab: explain why we're testing with load first before using chrt
    Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>


 labs/sysdev-real-time/sysdev-real-time.tex | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/labs/sysdev-real-time/sysdev-real-time.tex b/labs/sysdev-real-time/sysdev-real-time.tex
index d0f4ed1d..165d9887 100644
--- a/labs/sysdev-real-time/sysdev-real-time.tex
+++ b/labs/sysdev-real-time/sysdev-real-time.tex
@@ -170,13 +170,20 @@ Now, do the following tests:
   \code{99}, using the \code{chrt} command.
+The above tests should confirm that once your program is no longer
+alone in the system, if you don't run it with the top real-time
+priority, the worst case latencies can really be unbounded.
+Therefore, in all the next tests, the program will be run under
+heavy load and through \code{chrt}.
 \subsection{Testing the preemptible kernel}
 Recompile your kernel with \kconfig{CONFIG_PREEMPT} enabled, which
 enables kernel preemption (except for critical sections protected by
-Run the \code{rttest} program again, with workload, under this new
+Run the \code{rttest} program again under this new
 preemptible kernel and compare the results.
 \subsection{Compiling and testing the PREEMPT\_RT kernel}

More information about the training-materials-updates mailing list