about MaxPermSize of jvm option.

Document ID : KB000111486
Last Modified Date : 30/08/2018
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Question:
API Gateway 9.2 (Appliance).
The current java version is "1.8.0_102".

"- XX: MaxPermSize = 256 M" is set as the Java startup option.
Howerver, the corresponding memory area was changed from JDK 8 to metaspace.
So, it seems this option is not enable.

Is the Java option("- XX: MaxPermSize = 256 M") correct?
If it is incorrect how should it be changed?
Environment:
API Gateway 9.2
API Gateway 9.3
Answer:
In JDK 8.0 the Permanent Generation (PermGen) space has completely been removed and is kind of replaced by a new space called Metaspace.
The consequences of the PermGen removal is that obviously the PermSize and MaxPermSize JVM arguments are ignored and you will never get a java.lang.OutOfMemoryError: PermGen error.
The JDK 8 HotSpot JVM is now using native memory for the representation of class metadata and is called Metaspace.
So no need to use Java option("- XX: MaxPermSize = 256 M") for above JDK 8.0 versions

Alos, as of now there isn't a need to set a Metaspace size. 
Considering the major reason that Java made this change was to allow the JVM to dynamically adjust its size during runtime. 

for more info on metaspace https://dzone.com/articles/java-8-permgen-metaspace