Conclusion Because the concept of Metaspace and perm is mostly the same, an administrator performing a Java 7 to Java 8 upgrade can change the flags simply by running sed 'e/Perm/Metaspace/g'.

Prior to JDK8 class metadata and constants would live in an area called the “permanent generation”. In JDK8 PermGen has now moved to native memory, to an area known as the “Metaspace”.