preempt-rt with kernel 3.12


I did some tests with the linux-stable 3.12.6 kernel with the rt9 patch on a beagleboard.
Finally I did some latency tests which shew some strange results.

Testing with cylictest from the rt-tests I get an average latency at about 65us.
But max latency is about 4!

I am very interested if anybody got an 3.12-rt system up and running at much better


Hello Matthias,
do you still work with Kernel 3.12 and PREEMPT_RT ?
The question is, how you built the Kernel,
because I’m not shure how to inject the PREEMPT - Patch into Robert Nelson Kernel
if it is Cross Compile on Ubuntu.
Could it be done by the following lines:
#cd bb-kernel

#patch -p1 <[patch-3.12.24-rt37.patch](

I’m not shure what happend because there is no PREEMPT option in the following configuration menue

Thank you in advance