QLC PI becoming non-responsive

[cheltgar]

Hi

New to QLC+. I have it installed and running on a Raspberry Pi3, and used it at a gig for the first time on Saturday night.
I have my pedalboard (Line 6 HX Effects) sending midi into the pi to trigger the virtual console.

It was all running fine, then partway through the gig - stopped responding. I went to the web interface from my Mac, and that wasn't responding either. I rebooted the pi (I added a PSU with a switch to reboot, so a bit of a blunt was to do it), and it ran for another hour, then froze again. Again rebooted.

Now im not at the gig, I want to have the system running and hopefully diagnose what is going wrong - but dont really know where to start.

I have had the pi running for a couple of hours.... and its frozen again. If I go to the web interface (after freeze - was working when I started the pi) it says 'Can't reach the server', however I can ping and ssh onto the pi in this state.

Could you please give me any advise on how to diagnose, and I guess the first question is - where are the logs on the Pi
All I have been able to see so far (and only know the basics of unix) is using systemctl list-units --type=service the entry for qlcplus.service had state Loaded : Active : Exited -> Does this mean that it has crashed?
When I reboot the pi, it has the status Loaded : Active : Running

BTW - apart from the crashes - totally loving QLC+ !!!!

Kind regards

[SPOPATT]

Could you share your file so we can take a look?

[cheltgar]

Would love to, but that’s my first question. Where are the relevant logs located

[cheltgar]

Hi
Sorry for the nudge, but could someone please tell me where the qlc+ logs are located on a Raspberry Pi - any help would be really appreciated

[mcallegari]

There is no log. QLC+ is built in release mode so no logs are produced.
To debug an issue you need a debug build which is not provided unless you build QLC+ yourself.
We could help if you provide more details, otherwise you're on your own.
First thing that comes in my mind is overheating.
Try another Pi or keeping it colder.

[markzvo]

I had this issue and how I solved it was to use SATA SSD storage vs the microSD card (available with the Pi4).

[shad]

I have the same issue described above. The only clue about why it crashes is when I run it from the command line: /usr/bin/qlcplus -platform eglfs --nowm --web --web-auth --operate --open /root/.qlcplus/autostart.qxw
Within anywhere from 30 to 90 minutes I get: free(): invalid next size (fast)

[GGGss]

Your project does not look over complicated, whilst you have some CPU-intensive EFX running.
My eggs in your basket: a thermal problem where the CPU protects itself by shutting down cores (?)
There are some nifty aluminum cases available with passive cooling. I don't trust those with those mini blowers myself.
Even with the passive cooling case, built in a small flightcase, the Raspi still gets hands-friendly warm. Imagine the state of the CPU inside...

[shad]

Thanks for checking my project. I am running a raspberry 4B 4GB with an GeeekPi Thin ICE heatsink & Fan. /usr/bin/vcgencmd measure_temp reports temp=29.2'C, never seen it get above 32'C. I don't think it is over heating and shutting down cores. Other process remain running. Googling "free(): invalid next size (fast)" is some sort of memory error cause by an error in the code.

[GGGss]

To be honest, I didn't run the 4.12.7 yet on my raspi's...
What version do you run? Did you compile it yourself?

[mcallegari]

Usually when I need to debug this type of issues, I try to cut the problem in slices.
Since there are many factors influencing the outcome, I check each one of them one by one.
For example:
- try another raspberry (so validate your RPi)
- try your project on a PC (validate your project)
- try another power supply (validate external causes)
- try without IO connected (validate peripherals)
- start to remove pieces of your project until it doesn't hang (validate project quality)
- etc

I think you get the idea.