Reboot, does it wait for processes to finish?

Because I can't tell/see nlbwmnon commit the database on reboot I'd like it to save it on reboot. I've added below to the init script and can see it get processed in the log but want to know if it's a bigger database to save does the reboot command wait until the database is finished saving. I can see the database gets a new timestamp after reboot but using watch on reboot it doesn't appear to save without this in the init file.

shutdown() {
	# save to database
    /usr/sbin/nlbw -c commit
    logger -t nlbwmon "commit database before reboot"