RPI4 Raspbian 64 bit & LinuxCNC

Hi All

I have "succesfully" installed the image that Elovalvo mentioned above on a RPI4B-8G unit, but my values are not very good, not to say terrible.
Trying to speed up the boot process, I installed the system on the SD card, and then moved it to a 128GB SSD M.2 disk, running it from there.

Running "top" from command line - I'm barely getting below 2.50 and have seen numbers of 4.60.
Latency tests don't go below 100000ns - But i have seen values above 250000!
That said, latency is not my biggest concern, since I am going to use a 7i76e to control my mill,- but even then - numbers as big as 250000 - would that even work ?

I haven't connected the mesa board yet, since my dell 2418HT touch monitor is also bugging me. It's a very fine monitor, but I have a 1/2 inch black frame all way around the desktop, and I can't auto adjust the monitor, no to talk about thew flickering i sometimes get on the lower 1/4 part of the screen (but that's only when I use the attached mouse - which will be disconnected once touch is fully working).
According to this link - Dell 2814HT with Raspberry Pi 4 - the 2418HT should be working with RPI4, but maybe it's the LinuxCNC distro that needs tweaking..?
Also still working on getting the touch screen calibrated to actually point where I touch.

My biggest concern at the moment is the performance of the system though.
Aside testing different IsolCPUs settings, what else could i tweak on to get better performance ?

Any input is highly valued!

Thanks in advance

jnp1968 wrote:

Latency tests don't go below 100000ns - But i have seen values above 250000!
That said, latency is not my biggest concern, since I am going to use a 7i76e to control my mill,- but even then - numbers as big as 250000 - would that even work ?

250,000 is getting a bit marginal, but 100,000 is workable. 

I was able to lower my latency a good bit by disabling Bluetooth and wifi. And if you need more turn off audio.
My latency also got a bit better after giving it an overclock.

Disabling wifi and bluetooth really helped.
I am now getting numbers steady at 105000,- with 7 x glxgears running.
Starting youtube pushed it straight to 250000, but hen again - I won't be running youtube on this machine when its done. It pure CNC.
Without glxgears and youtube, I'm steady below 80000 - which should be fine accoring to Andypugh's comment
Enabling overclock actually just made it a lot worse - so i'm sticking with the above.
Thanks for the help
Also found a thread about the black border. It suggested that disabling overscan could solve it.
Gonna check that out later today.

interesting that the overclock made it much worse.
did you not only increase the clock but also voltage and gpu clock?
Also the RPi4 runs hot stock so a small 1" heatsink plus fan helps a ton.

Hello, 

I have successfully built the 5.10 RT kernel as well as compiled linuxcnc on a RPi with 64bit Raspbian. Axis GUI is working as well. However when I try to start Gmoccapy I get the following error: 

This looks to me like the python-gtksourceview2 module is missing. So I tried to install it with

This fails with the following message: 
But on the the 32bit version of Raspbian the package is available. 

Is the problem really linked to this missing package. If so, how can I solve this?

Best regards, 

Marc