Raspberry Pi OS PREEMPT RT 6.13 Kernel Cookbook

Hi gene_weber,

Thank you for the info. Back in November, 2024, I did managed to build and install a PREEMPT_RT kernel to my Raspberry Pi 4B:

[
Linux picnc 6.6.59-rt45-v8-behai-rt-build+ #1 SMP PREEMPT_RT Sat Nov 2 10:20:46 AEDT 2024 aarch64 GNU/Linux
]

But I did not know how to make other configurations as you have done: I did not know we have different displays, etc.

I have also built LinuxCNC from source and installed it from the build: only last week, I have found out that I have done a simulated-realtime version of LinuxCNC. PnCConf reports:

[
"You are using a simulated-realtime version of LinuxCNC, so testing / tuning of hardware is unavailable."
]

I did not know we can install LinuxCNC from a prebuilt package to a Raspbian OS as you have done.

Might I have a question, please? You use -j6 in the command:

[
make -j6 Image.gz modules dtbs 2>&1 | tee make.log
]

On my Raspberry Pi 4B, nproc reports 4, I use -j4.

So is it true that later Pi 4B revisions have more cores? I bought mine back in middle 2023. I don't have Pi 5 yet.

Thank you and best regards,

...behai.

 

No always 4 cores.

For some reason the RPi docs say to use -j6.

unknown wrote:

No always 4 cores.

For some reason the RPi docs say to use -j6.
 

Thank you Rob.

Yes, RPi suggests that parallel processing 1.5x that number of cores works well. I had also always used the number of cores.

This setup is for sale.

Best,  Gene