For large installs when you view the ports page for a device, it builds a large number of queries to work out port / device relationship from IPs and interfaces (on my install this equates to 9k mysql queries - yes I'm not joking).
I've added this as a quick fix to disable the support of this until more time can be spent on it. We're running it on our installs. Cuts our page load times down by a half.
Added flag to disable port relationship in ports list for a device