Java Unsafe APIs provides various low-level APIs which could be used by programmers but we should be very careful when to use these APIs. These APIs provide a way to access off heap memory in java.
Java Unsafe APIs
Tag: Heap
Understanding Long GC Pauses with JVMs
In Applications keeping large caches, when the old generation is occupied by strong referenced objects, applications tend to do FULL GCs each time young generation gets fully occupied.