Question

I have difficulty creating a memory dump for my unit tests which produce out of memory errors.

My MAVEN_OPTS contains the following:

-Xmx1024m -XX:-HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=C:\Temp

However, when I run my unit tests from the command line using “mvn install”, I do not get any such memory dump when the OutOfMemoryError occurs.

How do I get the memory dump?

Thanks

Answer 1

Maven (surefire-plugin to be precise) by default creates new JVM for running tests. MAVEN_OPTS variable is used by the JVM running maven itself, but not forked test JVM. To change settings of that JVM, use the following code snippet:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <!-- ... -->
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <configuration>
                    <argLine>-Xmx1024m -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=C:\Temp</argLine>
                </configuration>
            </plugin>
            <!-- ... -->
        </plugins>
    </build>

</project>