Skip to Main Content

Java APIs

Announcement

For appeals, questions and feedback about Oracle Forums, please email oracle-forums-moderators_us@oracle.com. Technical questions should be asked in the appropriate category. Thank you!

JConsole Question: What is Eden Space?

843798Oct 20 2008 — edited Dec 5 2008
I'm studying memory use of my app with JConsole. The docs (http://java.sun.com/javase/6/docs/technotes/guides/management/jconsole.html) say:

Eden Space (heap): The pool from which memory is initially allocated for most objects.
Survivor Space (heap): The pool containing objects that have survived the garbage collection of the Eden space.
Tenured Generation (heap): The pool containing objects that have existed for some time in the survivor space.
Permanent Generation (non-heap): The pool containing all the reflective data of the virtual machine itself, such as class and method objects. With Java VMs that use class data sharing, this generation is divided into read-only and read-write areas.
Code Cache (non-heap): The HotSpot Java VM also includes a code cache, containing memory that is used for compilation and storage of native code.

What is the difference between "eden space" and "survivor space"? The above descriptions don't make this clear.
Comments
Locked Post
New comments cannot be posted to this locked post.
Post Details
Locked on Jan 2 2009
Added on Oct 20 2008
2 comments
6,919 views