Why gnome restart has delay after update gdm configuration?
 

Sorry for my english!

I want to update gdm configuration with signal SIGUSR1 (kill -SIGUSR1 `cat /var/run/gdm.pid`), then i restart the system by gnome exit menu, the system is not restart immediately and bring me back to the gdm login UI, after about 30s delay, the system just restart, Why!!

My OS is Ubuntu.