How come my app is killed for mem pressure but all heap + VM doesn't grow?

If I profile my app with Instruments on my iPad Air (iOS 12.4), choose the Leaks instrument or the Allocations instrument, run it for a while, my app is killed due to memory pressure.


I'm trying to find my bug (it's possibly something to do with looped playback of videos), but i'm stymied: "All Heap & Anonymous VM" does not grow. It stays nice and low (about 110MB). Since the app keeps getting killed for memory pressure, I suppose i'm causing a leak outside of my app somehow (and i'm assuming this is my bug as i'm not doing anything unusual).


Where do I go from here? Can someone spot my faulty assumption / misunderstanding?

thanks.