Performance issues after switching from LCNC 2.8.4 Buster to 2.9.3 Bookworm

Aciera wrote:

Thanks Rod, I find it rather unfortunate that somebody like you does not seem be offered write access to the 'official' install documentation. The pull request process is so sluggish that by the time new install docs might actually make it through they're already outdated.

I have tried to keep my doc current but I have not installed on a problem PC for quite a while. It has been suggested the install ISO should install the R8168 driver as it should not get in the road. Not sure on that. (I built the ISO and the Pi images for Linuxcnc).

At one stage I was asked to edit the getting Linuxcnc docs and it included most of my documentation notes you refer to. This was accepted and was published in the 2.9 docs. However, when 2.9.1 was released, this was all blown away and replaced with content based on 2.8 docs.

I think there should be a new document added that might be called something like "System Optimisation for Linuxcnc", perhaps a seperate doc for the raspberry Pi it links to. If somebody was to have a go at that from my material, I would not have a problem. Asciidoc and I are not good friends.
I almost know enough about git to be trusted with write access... but time is an issue

Ok, I got a setup running with 2 EtherCAT drives without problems. I've now added a third EtherCAT drive and the problem has returned, occurring about once every hour or so. I check the tmax write plus the tmax read for the lcec which combined to max 23.5% of my servo loop time.
I would really like to turn off the r8168.aspm=0 or r8168.eee_enable=0 functions to see if that helps as rodw suggested, but I do not know how. The grub customizer does not allow me to save those, throwing a "not found" error.

Ok, it seems r8168.aspm=0 or r8168.eee_enable=0 cannot be set with the grub customizer, but found another way:

sudo geany /etc/modprobe.d/r8168-dkms.conf

add the following:

# Disable Energy Efficient Ethernet
options r8168 eee_enabled=0

# Disable Active State Power Management (ASPM)
options r8168 aspm=0

Then save and close geany, then run the command:
sudo update initramfs -u

Then reboot
sudo reboot

After the reboot you can verify that the energy efficient ethernet is indeed disabled with
sudo ethtool --show-eee enp2s0
replace enp2s0 with the name of your Ethernet interface. You can get the name of your interface with the "ip a" command
If ethtool is not installed do:

sudo apt update
sudo apt install ethtool

I'm now running an endurance test with EEE disabled. Will report back here.

Ah yes! After switching off EEE and aspm, I ran the machine for over 3 hours straight without encountering any servo following errors. I captured everything I did in order to do a full problem free installation in this procedure for my customers, this might be useful for others as well:

baxedm.com/linuxcnc-installation-for-edm...-on-linux-debian-12/

BaxEDM wrote:

Ah yes! After switching off EEE and aspm, I ran the machine for over 3 hours straight without encountering any servo following errors. I captured everything I did in order to do a full problem free installation in this procedure for my customers, this might be useful for others as well:

baxedm.com/linuxcnc-installation-for-edm...-on-linux-debian-12/
 

Nuce writeup. I hope you don't mind but I added it to my Debian 12 document
docs.google.com/document/d/1jeV_4VKzVmOI...diY/edit?usp=sharing