Enhanced Efficiency: Java 23 Released with Improved ZGC Operation Modes

Oracle has released Java 23, a short-term support version for 6 months (the latest LTS is Java 21).

Java 23 introduces a significant change in the Z Garbage Collector (ZGC) working mode, now using generational mode as default. Since testing began in Java 21, the result is improved performance in almost all cases. The old working mode, known as non-generational, will be phased out in the long term.

Other new features are still in preview status, such as Primitive Types in Patterns, Module Import Declarations, Flexible Constructor Bodies, Class-File API, Vector API, Scoped Values, and Structured Concurrency.

As Oracle opens up GraalVM for free in 2023, the GraalVM team launches Oracle GraalVM for JDK 23. It includes optimizations for smaller image sizes (compiler optimization), improved memory usage in Serial GC, and support for Python (GraalPy) and WebAssembly (GraalWasm).

TLDR: Oracle unveils Java 23 with improvements in Z Garbage Collector and previews new features, while GraalVM for JDK 23 enhances performance and adds support for Python and WebAssembly.