"MCU 'mcu' shutdown: Timer too close" error

Basic Information:

Printer Model: Biqu B1
MCU / Printerboard: Raspberry Pi 3A + SKR V1.4 Turbo
klippy (9).zip (1.9 MB)

Describe your issue:

I recently ran into a new error (I’d hoped I’d seen them all by now) about 9 hours into my 11 hour print

MCU 'mcu' shutdown: Timer too closeThis often indicates the host computer is overloaded. Checkfor other processes consuming excessive CPU time, high swapusage, disk errors, overheating, unstable voltage, orsimilar system problems on the host computer.Once the underlying issue is corrected, use the"FIRMWARE_RESTART" command to reset the firmware, reload theconfig, and restart the host software.Printer is shutdown

Setup is a Raspberry pi 3A and SKR V1.4 Turbo, klipper is a brand new install as of this week, so it’s up to date, installed via kiauh on raspberry pi os lite. No webcam, no input shaper, only 16 microsteps, pretty stock setup. I am using Obico, but the ai detection is off (because no webcam).

Anything I can check on the linux side to see what happened?

Edit: Also I obviously wasn’t watching top when this happened, but as it’s printing right now I can’t see the CPU usage go above 30% and memory has at least 100MB free out of 500 total. It doesn’t seem to be stressed.

Hello @jblack !

You can zip a log.

Not everyone does pastebin…

FYI, I’m not sure what the root cause was, but the log does indicate the host cpu got overloaded. The klippy python program was unable to get cpu time for about 400ms during the event.