Maybe it is also worth mentioning that I am using "remote debugging". The IDE is on the host system, while PHP and Xdebug are on the Guest system. Host is Ubuntu 14.04 64 bit, Guest is Ubuntu 14.04 32 bit

I am not sure if that was the problem, but it seems the HTML was loading too many files (around 1200), all with the debug session and maybe it caused some overflow or something. As I reduced them to around 40, it stopped crashing.

Not sure if that was a bug or a feature

Crashing is never a feature of course... I'd like to get to the bottom of this, but I'm going to need a way to reproduce this. That means code, and the exact ways how to get into this situation. I guess that means a remote debugging log (xdebug.remote_log=/tmp/remote.log) as well.

I had the same thing happening to me. I switched to apache-mod instead of fpm and it no longer times out after 30 seconds, but it still doesn't work right (stepping through the will jump around almost like two debugging processes are happening simultaneously).

I'm marking this as resolved/suspended as I can not reproduce this problem. I don't have the code to go with the remote debug log.

Please only reopen once you can provide the information as is outlined in https://xdebug.org/support.php#remote