Momentary (but consistent) CPU lock-ups when manually touching-off

Any idea why one (of my 4 [with the 4th core set with isolcpus]) CPU maxes out during manual touch-off setting?

Gmoccapy consistently becomes unresponsive for ~30 secs every time X, Y or Z offset is set.

Is this a known behaviour or do I have something set-up incorrectly?

I also get a lock-up when loading a 8MB G-code file. Does 8MB really take that long to process?

What is so CPU intensive about setting touch-offs? And why only 1 CPU; isn't Gmoccapy multi-threaded?

Any help would be gratefully received.

isolation of power supply required (complete isolation.... don't connect the and connections together) would be my suggestion

The larger the g-code program is loaded, the longer the touchoff takes. Don't know why.
30 seconds sound a long time, many seconds for a long program anyways,

Gmoccapy should honour these commands in the gcode:
linuxcnc.org/docs/2.8/html/gui/axis.html#axis:preview-control

If it's the loading of the large program that should help.
When you touch off linuxcnc must reload the program in the display.
It is not done in the background.

Not sure what you're trying to say @robertspark.

Ah okay, it makes sense about the larger program.

So long as it doesn't start locking up as I'm cutting, I guess I can live with it.

Doing touch-offs before loading larger programs makes a more pleasant experience, or at least that's true with the old computers I run.
Practical with my work flow most times, for others maybe less practical.