- There are two kinds of memory used in Java. These are called stack memory and heap memory. Stack memory stores primitive types and the addresses of objects. The object values are stored in heap memory.
- The primitive variables (local method variable) are allocated in the stack, but if they are member variables (i.e. fields of a class), they will be stored in the heap.
- In Java methods local variables are pushed into stack when a method is invoked and stack pointer is decremented when a method call is completed.
- In a multi-threaded application each thread will have its own stack but will share the same heap. The stack is threadsafe (each thread will have its own stack) but the heap is not threadsafe unless guarded with synchronisation through your code. This is why care should be taken in your code to avoid any concurrent access issues in the heap space.
stack and heap memory
why java is slow
http://www.itec.uni-klu.ac.at/~harald/CSE/Content/performance.html
http://www.phptr.com/articles/printerfriendly.asp?p=31755&rl=1
