How do you fully kill an ARSession?

I have an ARSCNView running an ARSession. You can pause the session with session.pause() sure, but that still in effect, leaves the session running. I have tried deallocating the ARSCNView by removing it from its superview. The ARSCNView indeed deallocates but the ARSession is still running afterwards!! You can't assign nil to ARSession either. I can see the ARSessionDelegate's

func session(_ session: ARSession, didUpdate frame: ARFrame)

is still being called!


How do you completely wipe the slate clean with ARKit once you have finished with it? I want it deallocated & gone.


Does anyone know?