Java 24 to Reduce Object Header Size and Save Memory

JEP 450 optimizes heap utilization in HotSpot by reducing the mandatory object header size, aiming to enhance deployment density and data locality.

The implementation of compact object headers allows for the shrinking of object headers in Java, which leads to lower heap size, improved memory efficiency, and potentially faster object access.

Java's mark word, critical for instance metadata like garbage collection and lock management, tends to be overwritten, complicating the implementation of the Compact Object Headers.

The klass metadata is stored in metaspace rather than in the Java heap, eliminating the need for additional Java object headers and separating class metadata from memory allocation.

Read at InfoQ