Server hangs / doesn't respond

[noyainrain]

Very rarely the server stops answering requests despite the process still running.

[noyainrain]

To further investigate the problem, we need a stack trace of the hanging process. This can be achieved with gdb (which has Python support, available in Debian package python3-dbg).

First we need to attach to the running process:

gdb -p {pid}

Then we can get the stack traces for all threads with:

thread apply all py-bt