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wellenvogel
Avnav/O-Charts collides with OpenCPN
I have the suspicion that Avnav using the O-Charts plugin collides with OpenCPN if both run on the same system.
Observation: I start Avnav at system startup up with the systemd service file. After the system is booted I start OpenCPN. It lags and eats up CPU and finally complains that something is wrong with the O-Charts (license, system changes, whatever). As soon as I stop the Avnav service OpenCPN immediately continues to work fine. After OpenCPN runs I can start the Avnav service again. Finally both seem to work in parallel but I'm not 100% sure since some lags occure in both programs with time.
Is it possible that the O-Charts servers of Avnav and OpenCPN try to use the same ports or whatever? I don't know how the communication between the software and O-Charts server works that I could further investigate that.
Currently there is not much I can do about this issue. The decoder for o-charts uses a (fixed) pipe at /tmp - and running 2 decoders at the same time could lead to problems. Basically from my tests it seems to work in most cases if you run both in parallel - but there could be problems as you see. As I do not control the code that is dealing with this part there is no chance... I'm working on a rewrite of the o-charts part - and this will also solve the parallel work problem. But this still takes time.
Ok, good to know.
I'll add PrivateTmp=yes to the systemd service file and report my result after testing.
yes, this seems to be a nice idea. If it works we can add this to the AvNav openplotter installer.
I have the suspicion that Avnav (or the AvnavOchartsProvider) may hang or misbehave if charts are updated within OpenCPN while Avnav is running. I know that this is somewhat vague. Since I discovered this first, I usually stop and restart the Avnav service when I update charts within OpenCPN.
But I can observe this more closely the next time when I update charts. Is there something specific where I could/should look at?
For sure this is not going to work without a restart of the ocharts provider (typically no need to restart AvNav). Just trigger the restart on the charts tab of the provider GUI.