Maven2 Heap Overflow in JUnit test cases: Howto increase memory

For the past few days I was wondering why Maven’s install gave me a Heap Overflow exception on JUnit tests on some of my machines. I tried increasing the memory by using the environment variable MAVEN_OPTS, by passing the option “-Xmx512m” to the JVM through Eclipse and from the command line. All to no avail.

Then I found this blog entry by Keith Chapman. And it worked! Here’s the solution in short:

The JUnit tests ignore the environment variable MAVEN_OPTS. You have to tell Maven’s surefire plugin to increase memory. Add this to your pom.xml file:

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-surefire-plugin</artifactId>
  <configuration>
    <forkMode>pertest</forkMode>
    <argLine>-Xms512m -Xmx512m</argLine>
    <testFailureIgnore>false</testFailureIgnore>
    <skip>false</skip>
  </configuration>
</plugin>