Anyone using Odroid H3?

I have 5 Odroid H3s (not H3+)......got pretty excited once i saw they were released and picked up a couple. I was probably the first person around here using an H2 for LinuxCNC.

I just got around to rebuilding the system on the H3 and RT performance is abysmal. I use Manjaro as it's alot easier to build LinuxCNC 2.8.4 and everything else I use as my buddy maintains the AUR packages. Manjaro has a pre-packaged 5.15 and 5.19 RT kernel.....both worked fine on previous tiny X86 PCs. I'm trying to figure out what's going on with the latency now, then I saw this thread...

The H3(+) requires a 6.x kernel to allow the graphics to work,

That's the first I heard that. I can't find any info about this on Odroid's forums. Graphics seem to work fine but I haven't spent any measureable time with it since LinuxCNC dies pretty quick from latency. Do you have a link? I don't have any indication that the display is running in software mode but I suppose that could explain the latency.

I also didn't see the thing about the RTL8125, my other H2's used the 1gb NIC except my router H2, the netcard uses the 8125. I'm gonna have to try that driver as I'm also getting alot of "HM2...Error finishing read" stuff but I figured it was just an overall latency issue. The AUR probably already has that driver in a PKGBUILD
 

blazini36 wrote:

I have 5 Odroid H3s (not H3+)......got pretty excited once i saw they were released and picked up a couple. I was probably the first person around here using an H2 for LinuxCNC.

So you are the one who got me onto the H2+  

isolcpus=2,3 will probably fix your RT problems
If you have the 5.19 kernel, I would try building the realtek driver whch the Odroid forum says is 15-30% faster than debian. Realtek don't say it supports the 6.x kernel
www.realtek.com/en/component/zoo/categor...pci-express-software

If you need the 6.x kernel you could try my kernel but I don't think you can use a.deb file on Manjaro.
forum.linuxcnc.org/9-installing-linuxcnc...dware-eg-realtek-nic
IN the folder on Drive there is a rough recipe. You could just change the command line switches to build and install.

Or retreat to Debian like me!

 

Manjaro just dropped a 6.0 rt kernel so I tried that which I was a bit hesitant to do because I had to update alot of packages. I typically don't update machines once they're setup....

And that killed it lol. Same problem I had when I setup the system from scratch. LinuxCNC will try to start  and get "USERMOT:Command Time out" errors all over the place. If I run latency-test it doesn't do anything, just starts with all the values staying at 0. I know this is due to some updated package, the only reason I got it to run in the first place is I used an image from a 4-month old setup on a similar PC. Any idea where to start to figure this out? No errors in dmesg or linuxCNC debug log other than the running terminal with the Usermot error.

I'm not a fan of Debian at all. Everytime I try to setup debian on this machine I abandon it because I need other outdated packages to run things besides LinuxCNC and they're gone from Debian and it's stuck in dependancy hell. Manjaro has everything on the AUR and up until now I could always get Manjaro running.

If I can't figure out what package broke LinuxCNC I may have to try Debian again anyway.

Just download a CD iso for Debian Bookworm non-free and install it specifyong the XFCE desktop (mandatory)
That will give you the 6,x kernel
cdimage.debian.org/cdimage/unofficial/no...builds/amd64/iso-cd/

Then type 
sudo apt install linuxcnc-uspace
sudo apt install linuxcnc-uspace-dev

And preempt_rt and linuxcnc will be installed by Debian magic!

I used to avoid Debian too but eventually found it was th eonly one that worked. Time to Surrender I think

I don't think I realized LinuxCNC was packaged as debs yet, though I don't use anything Debian based much.

I'll give it a try, hopefully Debian actually has a working installer now.

Looks like LinuxCNC has only been packaged for bookworm and it's 2.9.....I need 2.8.4, so looks like I'll be building it either way which I don't think will be easy for bookworm

If you use a 6.x kernel, you won't have any Python2 support so running Linuxcnc V 2.8 will be problematic on any platform
You need kernel version 5.9 and above to get support for your network card.
Linuxcnc 2.8 was built for kernel 4.9
You are between a rock and a hard place.

Debian Bullseye on kernel 5.10 is the first version of Debian that qualifies for your NIC.
There will be a number of hardware features that won't have full support on lower version of kernels.
You could use Bullseye but there ar no debs for it so you need to compile from source.

Bite the bullet and go to V 2.9 and leave all of the Python 2 incompatibilities behind. Bookworm is only a few months short of becoming the Debian release version.