This short article will provide you with a high level overview of the different Java Heap memory spaces of the Sun Java HotSpot VM. This understanding is quite important for any individual involved in production support given how frequent memory problems are observed such as OutOfMemoryError.



Future articles will cover more advanced topics such as the different Java Heap spaces such as Young Gen and Old gen associated to each particular garbage collection policy.





Please feel free to also visit the other posts below for case studies on real production system OutOfMemoryError problems.

HotSpot VM: 3 memory spaces





The JVM HotSpot memory is split between 3 memory spaces:





· The Java Heap

· The PermGen (permanent generation) space

· The Native Heap (C-Heap)