Panel Caching Eviction Policy?

The only information about panel caching that I’ve found is here: Defer Data Load — Panel v0.13.1
and here:
Performance and Debugging — Panel v0.13.1

I’d like to understand how panel reacts when the system begins to run out of memory because there has been too much caching. what is the eviction policy? Can we increase the priority of some cached items so they do not get evicted while others do?

Thank you very much!