jenkins slaves out of memory

Hello I see jobs failing on out of memory problem [ERROR] OutOfMemoryError: Increase heap size or lower gwt.jjs.maxThreads http://jenkins.ovirt.org/job/ovirt-engine_create_rpms/label=f19-gwt/1211/... can anyone plz recommend to me what should be changed and for what value? current mavenopts are export MAVEN_OPTS="-XX:MaxPermSize=768m -Xmx512m -Djava.io.tmpdir=$WORKSPACE/tmp" Thanks, Ohad