System latency search

AMD FX(tm)-6100 Six-Core Processor
CPU max MHz:         3300,0000
Mem:       12'003'464
2.8.4 on new ISO installed on new 128Gb SSD
Linux 4.19.0-21-rt-amd64 x86_64
And yet:
Servo thread 435830
Base thread 238313
How do I identify the source of my problems?

While writing the previous post, already 2979037 and 258006 respectively.

uname -a
Linux INVENTOR 4.19.0-21-rt-amd64 #1 SMP PREEMPT RT Debian 4.19.249-2 (2022-06-30) x86_64 GNU/Linux

If ACPI Function is set to [Disabled], the computer hangs at the "Loading initial ramdisk..." loading stage. What should I fix?

The thing is that the problems with the delay started after some update, maybe from 2.7 to 2.8 or something like that. Before that everything was fine, on the same BIOS settings, on the same computer.
Until recently, I didn't pay attention to the messages about the delay at startup and worked quietly. But now the machine has a frequency converter and I can't set the PWM. When I change the spindle speed, the pulse rate does not change. Maybe the delay is the reason for that?

If you updated from an older 2.7 version using a RTAI kernel to an newer version of 2.8 and a Preempt-RT kernel. That is a big change and a lot of hardware that works well with one may not work very well with the other. You may need to look into switching back to an RTAI verion (if that is what you had before.)

Yes, I've already thought about it. In that case, do I have to reinstall the system again or can I somehow roll back to the previous version?

If you installed the newer Linux version beside the old one instead of overwriting it, then yes, but that is very unlikely, unless you purposely chose to do that when installing the new OS.

You should at least be able to make backup copies (or have them already) of your machine's configuration files. Saving them back to the new "old" Linuxcnc installation should at least save you from having to remake them.

However reinstalling older obsolete versions of Linux can be an arduous task because the old Linux (Debian or Ubuntu) repositories for them are no longer available on the internet. So installing or updating any programs other than are included on your installation media can be difficult or impossible.