@rodw
Don't think that is the problem. Could be it is fixed. I've had another day without a problem. Will let it run a week or so.
Could be I've fixed it by uncommenting the hardware−irq−coalesce−rx−usecs 0 line. (Can't remember why I commented it out before?) I've also turned turbo off.
,.,.
OT:
(not sure how turbo works? It is described by Intel as:
"Intel® Turbo Boost Technology 2.0 accelerates processor and graphics performance for peak loads, automatically allowing processor cores to run faster than the rated operating frequency if they’re operating below power, current, and temperature specification limits. Whether the processor enters into Intel® Turbo Boost Technology 2.0 and the amount of time the processor spends in that state depends on the workload and operating environment."
What it doesn't say is if it uses the ME processor (this is a separate processor in the same chip) to check current/temperature in a way that preempts. I've had AMT off in the BIOS (ME(Management Engine)) - but it seems possible that turbo uses the management engine processor? - which would be bad. (Management engine work preempts other tasks).
What is clear is that not only linuxCNC - but video/audio production, VoIP, etc need uninterrupted processor support - there was a time when Intel produced industrial mother boards with this in mind. What changed is 'secure-boot' (which is the OPPOSITE of what it sounds like) seems to have been mandated by three letter folks without public knowledge or consent.
It would be nice to find a platform that supports core-boot on modern hardware - clean of binary blobs.
coreboot.org/status/board-status.html
Beyond coreboot - it is important to understand that modern systems just don't execute instruction in knowable clocks - even with simple ARM core chips - you can't trust that a flash read will happen in the same time twice. Same with setting up PCI-e transfers. This shouldn't matter in a system (like MESA) that uses hardware counters - but breaks software loop timing of I/O.
So the actual processing power to run LinuxCNC is quite modest - it is the preemption latency problems caused by the ME and binary blobs that cause problems.
