Use -XX:+Flags=<file>. You can specify *ONLY* "-XX" options. OpenJDK checks this option when vm parses the arguments as following. JDK9 jdk9/jdk9/hotspot: 18218f0736d2 src/share/vm/runtime/arguments.cpp JDK8 jdk8u/jdk8u/hotspot: 9d6eb2757167 src/share/vm/runtime/arguments.cpp