Running on a Linux server, yes?
Something is interrupting the system call. Could be that it's trying to perform an invalid call. What else is running at the same time as the server?
It's also not finding your Linux home directory via getpwuid().
Because of both those issues I'm wondering if it's a problem in your Linux server OS, but it could also be a bug in the Avorion server running on Linux, since you don't appear to be using the Steam authentication, so maybe it's a bug with the TCP/UDP method.
This is just what I briefly gleaned from the thread data there and the signals being sent. Nothing that you can fix if it's in the server.