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 variables
if not exist "%CATALINA_BASE%\bin\setenv.bat" goto checkSetenvHome
call "%CATALINA_BASE%\bin\setenv.bat"
goto setenvDone
:checkSetenvHome
if 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 directory
find: /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.