Real Time PREEMPT_RT Kernel Tuning including Networking

My latest video is 28 minutes of pure gold for those needing to minimize network and system latency on Debian Bookworm and Trixie

The info assembled here is scattered and its never been available in one place. Also, many articles on the internet refer to obsolete applications no longer in Debian Bookworm or Trixie (for good reasons).

This video covers how to:
1. Configure the GRUB kernel settings
2.  CPU Governor set to performance
3. NIC coalescence disabled for Intel network cards
4. Network driver correctly installed and configured
5. CPU core isolated for LinuxCNC Real time process.
6. IRQ for Network card identified and set to Isolated core
7. Outlines why irqbalance should NOT be installed

Also, whilst kernel documentation states energy efficient ethernet is disabled by default but this is not always the case. Whilst some NIC's allow it to be disabled with GRUB parameters, there is no standard so different network interfaces need different treatment with hard to find parameters. We show how to create a service that disabled all NIC's. This requires a configuration file attached (to be used in conjunction with the video) that I have attached as a convenience here.

This has been one of the hardest LinucCNC tutorials I have ever put together. Please provide feedback here and as comments on the Youtube video. Enjoy!

 

You might also want to disable IPv6 on the card, otherwise there are
some discovery packets sent. After the card is up, I use the following
command to turn of IPv6:

sysctl -w net.ipv6.conf.eth1.disable_ipv6=1