? RTAPI: ERROR: Unexpected realtime delay on task 1 ?

Hello everybody,

I have an IBM Thinkpad 2668.
Pentium M
1.86 GHz
2GB of memory

On linuxcnc.org I downloaded the live image and installed it on the laptop.

I was able to set up my machine well on Linuxcnc and it also runs.
However, I have 2 problems:

1) Every now and then the program Linuxcnc simply hangs, then nothing works.
2) Almost always the following error message appears: "RTAPI: ERROR: Unexpected realtime delay on task 1. This Message will only display once per session. Run the Latency Test and resolve before continuing."

Latency test shows a value of approx. 6000 at idle.

I've tested all sorts of configuration values, no change.


can it be that these problems hang together?

There are no USB devices or other external hardware connected.

I did 5 tests without connecting the parallel port, also without a machine. -> 1x it stuck, 4x came the error message, once ran through without problems.


I hope you have a tip for me!

In a forum I read that one should install a smaller Linux with old computers and Linuxcnc manually install, that runs then better !?

Thank you!

Now i got a cheap i5 PC with serial interface.
Someone told me, that Laptops often have Problems with the realtime Kernel.

Now it works perfectly without Problems!