How to deal with “java.lang.OutOfMemoryError: PermGen space” ?

How to deal with “java.lang.OutOfMemoryError: PermGen space” error?

Common mistakes people make is thinking that heap space and permgen space are same, which is not at all true. You could have lot of space remaining in the heap but still can run out of memory in permgen.

Common causes of OutofMemory in PermGen is ClassLoader. Whenever a class is loaded into JVM, all its meta data, along with Classloader, is kept on PermGen area and they will be garbage collected when the Classloader which loaded them is ready for garbage collection. In Case Classloader has a memory leak than all classes loaded by it will remain in memory and cause permGen outofmemory once you repeat it a couple of times. The classical example is Java.lang.OutOfMemoryError:PermGen Space in Tomcat.

Now there are two ways to solve this:
1. Find the cause of Memory Leak or if there is any memory leak.
2. Increase size of PermGen Space by using JVM param -XX:MaxPermSize and -XX:PermSize.

You can also check 2 Solution of Java.lang.OutOfMemoryError in Java for more details.


Refer to:

Some Useful -XX Options
 
Default values are listed for Java SE 6 for Solaris Sparc with -server. Some options may vary per architecture/OS/JVM version. Platforms with a differing default value are listed in the description.

Boolean options are turned on with -XX:+<option> and turned off with -XX:-<option>.
Numeric options are set with -XX:<option>=<number>. Numbers can include 'm' or 'M' for megabytes, 'k' or 'K' for kilobytes, and 'g' or 'G' for gigabytes (for example, 32k is the same as 32768).
String options are set with -XX:<option>=<string>, are usually used to specify a file, a path, or a list of commands