It was noticed that following process keep growing with maven jobs configured on 1.6. I suspect that on Job failures / premature stop does not kill the processes and so the count of these processes keep on growing. This behavior was not observed while using JDK 1.7 to run the job

"/opt/jdk/java6/bin/java -cp /home/svc-ci/maven3-agent.jar:/opt/mvn/boot/plexus-classworlds-2.4.jar org.jvnet.hudson.maven3.agent.Maven3Main /opt/mvn /home/svc-ci/slave.jar /home/svc-ci/maven3-interceptor.jar /home/svc-ci/maven3-interceptor-commons.jar 38015"