what does the "Allocated" mean in the hover card?

[makesimple]

Hi, here is the explanation about the "Allocated" in this page : "Allocated: Current capacity of the heap is typically slightly larger than total size of all heap objects." I have some questions about this explatnation:

1. Does the heap mean flutter heap?
2. If it's flutter heap, Is it a part of RSS or Virt ? which one?
3. If it isn't flutter heap, what is it compose of? Allocated=Dart/Flutter + Dart/Flutter Native ?

Thanks