If I download on-demand-resources during an app session, either calling endAccessingResources() or dealloc'ing the triggering NSBundleResourceRequest will mark the content as "surplus to requirements", effectively. That content may be purged.
I'm trying to understand when that would occur.
WWDC'2015 session 214 discusses this at around 32minutes in. They say resource packs are only purged when the system is low on space. They also say that asset packs are selected for deletion based on the time of last usage and preservation priorities.
I didn't hear anything about which apps are examined and in what order. Is it like memory, where the apps are ranked and examined based on highest consumption of apps not presently running first?
Or is it just about the max 2GB of ODR data in use at any given time, so per app?