Tomcat – java.lang.OutOfMemoryError: PermGen space

Often time, Tomcat may hits the following java.lang.OutOfMemoryError: PermGen space error.

Java

java.lang.OutOfMemoryError: PermGen space        at java.lang.ClassLoader.defineClass1(Native Method)        at java.lang.ClassLoader.defineClass(ClassLoader.java:620)        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)

It’s usually happened after the Tomcat restarts a few times.

1. Solution

By default, Tomcat is assigned a very little PermGen memory for the running process. To fix it, increase the PermGen memory settings by using the following Java VM options.

Bash

-XX:PermSize<size> - Set initial PermGen Size.-XX:MaxPermSize<size> - Set the maximum PermGen Size.

In the next step, we will show you how to set the VM options in Tomcat, under Windows and Linux environment.

2. Windows

Tomcat is managed by this script file catalina.bat, dive inside the script, you will find out that catalina.bat always find and run the setenv.bat file to set the environment variables.

{$tomcat-folder}\bin\catalina.bat

Bash

//...rem Get standard environment variablesif not exist "%CATALINA_BASE%\bin\setenv.bat" goto checkSetenvHomecall "%CATALINA_BASE%\bin\setenv.bat"goto setenvDone:checkSetenvHomeif exist "%CATALINA_HOME%\bin\setenv.bat" call "%CATALINA_HOME%\bin\setenv.bat":setenvDone//...

2.1 To set the environment variable on Windows, create a setenv.bat manually, and put it into the ${tomcat-folder}\bin folder.

${tomcat-folder}\bin\setenv.bat

Bash

set JAVA_OPTS=-Dfile.encoding=UTF-8 -Xms128m -Xmx1024m -XX:PermSize=64m -XX:MaxPermSize=256m

P.S No double quotes, set JAVA_OPTS={value}.

2.2 Restart Tomcat, it will call the setenv.bat file to set the environment variable automatically.

Bash

{$tomcat-folder}\bin\catalina.bat restart

3. Linux

On Linux, the process is same, just Tomcat is using catalina.sh and setenv.sh instead.

3.1 Find out where is catalina.sh :

catalina.sh

Bash

$ sudo find / -name "catalina.sh"Password:find: /dev/fd/3: Not a directoryfind: /dev/fd/4: Not a directory/Users/mkyong/Downloads/apache-tomcat-6.0.35/bin/catalina.sh

3.2 Review the catalina.sh, script, it behaves like Windows, but use setenv.sh instead.

Bash

//...# Ensure that any user defined CLASSPATH variables are not used on startup,# but allow them to be specified in setenv.sh, in rare case when it is needed.CLASSPATH=if [ -r "$CATALINA_BASE/bin/setenv.sh" ]; then  . "$CATALINA_BASE/bin/setenv.sh"elif [ -r "$CATALINA_HOME/bin/setenv.sh" ]; then  . "$CATALINA_HOME/bin/setenv.sh"fi//...

3.3 Create a setenv.sh manually, and put it into the ${tomcat-folder}\bin\ folder.

${tomcat-folder}\bin\setenv.sh

Bash

export JAVA_OPTS="-Dfile.encoding=UTF-8 -Xms128m -Xmx1024m -XX:PermSize=64m -XX:MaxPermSize=256m"

P.S With double quotes, export JAVA_OPTS=”{value}”.

3.4 Restart Tomcat.

Note
The heap size and non-heap size (perm gen) value is just an example, you should change the value accordingly to suit your project needs.