ODroid as raplacement for Raspberry Pi

Running

I end up with

The max latency numbers are interesting because they are significantly higher than I was seeing before. I'm going to dig deeper because I'm not sure what would cause that.
 

I'm not really familiar with cyclictest but I see the average is very close to the min.
Do you see any 2 digit actual numbers flashing up?
I think the max figures are one off outliers otherwise the averages (3, 4 or 5) would be a lot higher.
maybe at startup or something.
 

> I see the average is very close to the min.

I noticed the same thing. The max is > 10x the avg which seems odd. The max does climb slightly over time, so it's not related to startup.

I'm going to do some reading and try to figure out how to capture some data on whatever may be causing these spikes.

you could try old schooland see where the spikes are...

The numbers from latency-histogram are basically the same. I started just running cyclictest because there's usually not much difference.

It may be worth building the kernel with ftrace enabled. Apparently cyclictest will record a trace of what the kernel was doing when there is a latency spike if you add `--breaktrace= 50 --tracemark`

stackoverflow.com/questions/52033624/ena...acteristic-of-system

Apparently we can also look for latency introduced by things happening within ARM TrustZones by enabling the Hardware Latency Tracer:

access.redhat.com/documentation/en-us/re...ow-latency-operation

rodw wrote:

We got an early result!
The PREEMPT_RT kernel has been kept seperate from the image as its quicker to just build the kernel at this stage when trying
Go to my drive
drive.google.com/drive/folders/1yZJ1_14W...CekVJOER?usp=sharing
download the image and install it to an SD card (not eMMC at this stage) with Balena Etcher
Download and install the 4 debs with: sudo dpkg -i kernel-name.deb
Install linuxcnc with:
sudo apt install linuxcnc-uspace linuxcnc-uspace-dev mesaflash

Optionally play with isolcpus as thats not optimised yet.
Edit /boot/armbianEnv.txt
Enter: extraargs=isolcpus=2,3,4,5

Let us know how you got on
 

I am getting my butt kicked. I got the image burned to SD with Balena, SD installed and I can SSH in to the odroid and get it configured however it doesn't launch the desktop and I can't get it to. 
I get this

ckcplasmaodroid@odroidn2:~$ startxfce4
/usr/bin/startxfce4: Starting X server
/usr/bin/startxfce4: 122: exec: xinit: not found

Secondly when I try to install the 4x debs I have them  on a USB but I can't figure out via command line how to move them, then install them. 
If I could get the desktop to work I won't be so helpless. 
 

Something is odd here.

Did you use my image or one from the Armbian site?
Maybe I had the wrong image in drive.
Try this image of mine.
drive.google.com/file/d/1QyaiQRC5UeyPJix...vQk/view?usp=sharing
It should give you the xfce desktop
The USB will just open in the file explorer.

You can make  a new top level folder on the SD card while its on the host (reinsert after burning) and copy the debs there. You might need to use Sudo on the droid.
I've also created the user and put the SD back into the host and copy files to the home directory

you can install the debs with sudo  dpkg -i mydeb.deb
this is where the tab auto complete is useful

eg. sudo dpkg -i linux-header(tab)
I'll have a look tonight.


 

rodw wrote:

Something is odd here.

Did you use my image or one from the Armbian site?
Maybe I had the wrong image in drive.
Try this image of mine.
drive.google.com/file/d/1QyaiQRC5UeyPJix...vQk/view?usp=sharing
It should give you the xfce desktop
The USB will just open in the file explorer.

You can make  a new top level folder on the SD card while its on the host (reinsert after burning) and copy the debs there. You might need to use Sudo on the droid.
I've also created the user and put the SD back into the host and copy files to the home directory

you can install the debs with sudo  dpkg -i mydeb.deb
this is where the tab auto complete is useful

eg. sudo dpkg -i linux-header(tab)
I'll have a look tonight.


 

The image I used was "Armbian_23.02.0-trunk_Odroidn2_bookworm_edge_6.2.0_xfce_desktop.img"  
It has the desktop in the file name like it should?

I am going to try the new one now. 
Thanks for looking into this. 

I can't get the desktop to load on this image either, it says "loading desktop environment" but nothing I do gets it to load.

I don't really have the skills to do ALL that it takes via terminal..

I am using ssh to log in, that shouldn't matter right?
I create a root password and a user, startxfce4 gives me the no init file error same as I posted above..