A memory pool from which you can suballocate resources.
- iOS 10.0+
- macOS 10.13+
- UIKit for Mac 13.0+Beta
- tvOS 10.0+
You suballocate resources from a heap and make them aliasable or non-aliasable. A sub-allocated resource is non-aliased by default, preventing future resources allocated from the heap from using its memory. Resources are aliased when they share the same memory allocation on a heap.
All resources sub-allocated from the same heap share the same storage mode and CPU cache mode. You can make heaps purgeable, but not the resources allocated from the heap; they can only reflect the heap’s purgeability state.