Monitor Latency while running linuxcnc?

Hi all!

As I allready mentioned in my other thread, I am getting totally different latency values in latency-test and latency-plot.

Is it possible to run linuxcnc and monitor latency? I would like to see which of the tools shows the correct values...

Thanks
DomCa

Do you get the realtime error while running Linuxcnc?
Leave it running and watch youtube or surf the web or do whatever to load the computer, if something is wrong you get the delay error for base and servo thread.

Hi tommylight,

thanks for the tip. I am building my CNC at the moment and do not have a machine to test with. And I am new to LinuxCNC...

Can I select the simulation when starting LinuxCNC? Will this also show the error? If yes, can I see/set the jitter limits set for the simulation?

Or do I hace to setup a machine with stepconf? Will this work if nothing is attached?

I want to get the PC with LinuxCNC running while I build my machine. That's why I am allready asking without the machine being finished...

Thanks for the support!
DomCa

There is sort of a way, there are some instructions in this thread.
forum.linuxcnc.org/38-general-linuxcnc-q.../31323-hal-histogram

I would be more inclined to trust the results from the latency plot or latency-histogram. There has been some discussion in the past about the ordinary latency test being slightly flawed, and not giving true real world results.

Hi Todd,

thanks for the info. I will have a look at the thread.

If the latency-plot is the correct one, I am in trouble...

Thanks,
DomCa

DomCa wrote: Can I select the simulation when starting LinuxCNC? Will this also show the error? If yes, can I see/set the jitter limits set for the simulation?

Yes, using a sim-config and the realtime core is just as valid a test as running with actual hardware attached.

Hi andy and Todd,

thanks for the info.
I now run linuxcnc and monitor latency as shown in the thread linked to by Todd.

I can run the sim with constant max latency of 13000. That seem ok to me for a start with linuxcnc.

However, I think it is important to notice that latency-test and latency-plot show totally different values than the HAL histogram (which I take as the correct)...

Now I have to build my CNC...

Thanks for the support and keep up the good work!

Domca