Скачать или смотреть Java Heap Memory Internals - Interview Cracker Concepts

The JVM has a heap that is the runtime data area from which memory for all class instances and arrays are allocated. It is created at the JVM start-up.
Also, the JVM has memory other than the heap, referred to as non-heap memory. It is created at the JVM startup and stores per-class structures such as runtime constant pool, field and method data, and the code for methods and constructors, as well as interned Strings.
Most of the newly created objects are located in the Eden memory space.When Eden space is filled with objects, Minor GC is performed and all the survivor objects are moved to one of the survivor spaces.
Minor GC also checks the survivor objects and move them to the other survivor space. So at a time, one of the survivor space is always empty.Objects that are survived after many cycles of GC, are moved to the Old generation memory space.