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HotSpot Internals

This wiki is written by and for programmers working on the HotSpot JVM system.

This wiki contains:

An architectural guide to the Runtime, Compiler, GC, Serviceability, etc.
Details on performance techniques.
A place to document likely future work (major refactorings or cleanups, new optimizations, etc.).
Quick links to similar information in other places on the web.
- http://java.sun.com/javase/technologies/hotspot ("Java SE HotSpot at a Glance")
- http://openjdk.java.net/groups/hotspot/ (OpenJDK HotSpot Project home)
- http://www.ssw.uni-linz.ac.at/Research/Papers/ (HotSpot-related research at the University of Linz)
Information which, once written, is expected to remain accurate and relevant, as long as the related code remains stable.

Please look for the following types of information elsewhere:

Not non-architectural or non-technical developer notes.
Not an introduction or quick-start for working on the JVM. (TO DO: Put links here.)
Not build instructions.
Not a substitute for comments in the source code.
Not a list of bugs or tasks.
Not a blog, forum, or the comments section thereof.

Extract links and info. from messages and blog postings, especially via hotspot-dev@openjdk.
Extract links and info. from historical Sun mailing lists and wikis. (Sun engineers have to do this!)
Write down understandings of major modules as they are (re-)acquired from trips through the code.