With Java 10, the default configuration only enabled class data sharing for JVM's bootstrap class loader. Since the bootstrap class loader doesn't load your application's files, you were expected to explicitly enable it for the application class loader and other class loaders using the following command:

    -XX:+UseAppCDS

With Java 11, however, AppCDS is automatically enabled with OpenJDK 64-bit systems. When including this option, you might get an error message like this:

If you are using Java version 11 or later, you can skip this option.