lcnc2.9 latency-test bug ?

It is after launch the latency-test, and of course the values are not possible.

I suspect a bug, that causes "rtapi error" messages after run axis or other gui.

Are you sure you are running a realtime enabled kernal?
What result does the command "uname -a" show in a terminal?

Todd Zuercher wrote: Are you sure you are running a realtime enabled kernal?

This is 4.14.148-rtai-amd64 patched from github.com/NTULINUX/RTAI/ and compiled myself.
It is of course realtime and gives extremely low latency, not exceed 5000 on my hardware.
Picture I attached shows not impossible situation, because max_interval=base+max_jitter.
If jitter is 25000 and base is 25000 than max interval should be 50000.
So, at start, jitter measure must be bad, I suppose.
Maybe it is the same reason to "rtapi error" message at start of linuxcnc gui ?


This is a good measure, after "Reset Statistics" :

I'm not so sure the Max Interval needs to necessarily be equal to sum of the Max Jitter and thread time, because the time intervals before and after the Max Jitter point may have been significantly shorter than planned.

Regardless, perhaps running the Latency-histogram or Latency-plot might be more telling (specifically the Latency-plot.)

Another curiosum - interval=210ns
This is Ryzen5 3400G/Gigabyte A320M-S2H V2, kernel 5.2.21-rt13, Xubuntu 18.04