How to identify slow unit tests when using maven-surefire-plugin in parallel mode?

Question

With a view to managing / reducing our build times, I want to identify which unit tests are taking the most time - in a parallel test environment using the maven-suref

Answer 1

Adding to the Maven Surefire Plugin configuration the reportFormat entry and setting its value to plain (instead of the default brief) would give you elapsed time per method.

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-surefire-plugin</artifactId>
            <version>2.19</version>
            <configuration>
                <argLine>-Xmx2G -XX:MaxPermSize=1G -XX:-UseSplitVerifier</argLine>
                <failIfNoTests>false</failIfNoTests>
                <parallel>classesAndMethods</parallel>
                <useUnlimitedThreads>true</useUnlimitedThreads>
                <reportFormat>plain</reportFormat>
            </configuration>
        </plugin>
    </plugins>
</build>

Output with default reportFormat (brief):

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running com.sample.mocking.InternalServiceTestCase
Tests run: 4, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.241 sec - in com.sample.mocking.InternalServiceTestCase

Output with plain value:

-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running com.sample.mocking.InternalServiceTestCase
Tests run: 4, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.187 sec - in com.sample.mocking.InternalServiceTestCase
test(com.sample.mocking.InternalServiceTestCase)  Time elapsed: 0.005 sec
mockTest(com.sample.mocking.InternalServiceTestCase)  Time elapsed: 0.17 sec
mockTestFailureTollerance(com.sample.mocking.InternalServiceTestCase)  Time elapsed: 0.007 sec
mockProcessfile(com.sample.mocking.InternalServiceTestCase)  Time elapsed: 0.003 sec

This option may give you further details on tests and execution time.