Interpreting the contents of the hs_err_pid file

Question

Below is a part of the hs_err_pid

Heap
 PSYoungGen      total 13888K, used 9807K [0x8a330000, 0x8b140000, 0x914f0000)
  eden space 13504K, 69% used [0x8a330000,0x8ac67710,0x8b060000)
  from space 384K, 96% used [0x8b0e0000,0x8b13c6e0,0x8b140000)
  to   space 448K, 0% used [0x8b060000,0x8b060000,0x8b0d0000)
 PSOldGen        total 115456K, used 57684K [0x514f0000, 0x585b0000, 0x8a330000)
  object space 115456K, 49% used [0x514f0000,0x54d451c0,0x585b0000)
 PSPermGen       total 16384K, used 11253K [0x4d4f0000, 0x4e4f0000, 0x514f0000)
  object space 16384K, 68% used [0x4d4f0000,0x4dfed618,0x4e4f0000)

What are

1. PSYoungGen
2. eden space (from space, to space)
3. PSOldGen
4. PSPermGen (object space)

Answer 1

These are the memory regions used by the garbage collector.

See the memory management whitepaper from Sun (PDF) for more details.

Answer 2

This is your Java HotSpot Garbage Collection source of information.

HotSpot Generations

Memory in the Java HotSpot virtual machine is organized into three generations: a young generation, an old generation, and a permanent generation. Most objects are initially allocated in the young generation. The old generation contains objects that have survived some number of young generation collections, as well as some large objects that may be allocated directly in the old generation. The permanent generation holds objects that the JVM finds convenient to have the garbage collector manage, such as objects describing classes and methods, as well as the classes and methods themselves.