Azul’s Java Performance Engineering Lab continually tests the code speed of Azul Zing’s distribution and other OpenJDK distributions in the market, using Java 11.0.6 as a baseline. Recent benchmarks have included JDK 21 performance. JDK 21 is the most recent LTS version, released in January 2024. What are the implications of these benchmarks for upgrading to JDK 21? Considering upgrading to Java 21? Your best option would be a high-performance Java platform. Prime includes Azul Zing, an award-winning enhanced build of OpenJDK for superior application performance, responsiveness, and efficiency.
Azul’s Java Performance Engineering Lab has observed a measurable reduction in garbage collection (GC) pauses since OpenJDK introduced Generational ZGC in Java 21. Azul’s benchmarks measure overall code speed, not just GC, but Generational ZGC has had an impact.
Key findings in this report:
The key findings that relate to Java 21, out of the gate:
- In January 2024, Zing JDK 21 (24.01) was 36% faster than the baseline of OpenJDK 11.0.6 – delivering far more performance out of the gate.
- OpenJDK 21 contains a new generational GC (ZGC), which reduces stop-the-world GC pauses. However, Azul Zing delivers higher performance gains vs. OpenJDK 21 from the first test.
As noted in our January 16, 2025 blog post, Java Application Performance Comparison: Azul Zing and OpenJDK, Zing versions improve in performance over their existence, while OpenJDK versions remain static. This is likely to be the case for JDK 21 performance.
So you can get faster code speed with Zing 17 without upgrading to Zing 21. But if you decide to upgrade, you still get increased performance with Azul Zing.
Plan now for JDK 25
The next LTS Java release, JDK 25, will be released in September 2025. Zing 21 performance will be far more impressive than OpenJDK 21 then if we extrapolate from historical performance and current benchmarks.
If you are an Oracle JDK 21 user, you will have one year to upgrade to JDK 25 or you will have to start paying for Java based on an employee-count metric.
What other options will you have?
- Stay with Oracle, very likely pay more, and have less performance than Azul Platform Prime offers.
- Switch to a non-Oracle Java paid distribution with paid support and very likely pay less (66% of such companies in Azul’s Oracle Usage, Performance & Migration Survey and Report said they now pay less than they did with Oracle) and enjoy better performance and lower cloud costs.
What makes the performance better?
Azul Platform Prime includes Azul Zing, an award-winning enhanced build of OpenJDK. With Zing, what you run in production today will run at least 20% faster, without the need to change or recompile your code.
We continue to work with our customers and the Java community to benchmark and increase Zing’s performance to improve how fast your code can go. Zing just keeps getting faster at getting faster.
Try Azul Platform Prime for free today. Azul’s high-performance Java platform helps you maximize efficiency and minimize costs by delivering pauseless garbage collection, faster code, and faster warmup times. Azul Platform Prime is TCK-verified with Oracle’s Technology Compatibility Kit, a test suite that verifies that the Java implementation is compatible with the Java SE specifications. The platform includes Azul Zing Builds of OpenJDK, which is enhanced for superior performance, consistency, and efficiency.
Azul’s high-performance Java platform uses fewer resources to achieve the same or even greater performance. This efficiency enables organizations to save on infrastructure costs, especially expensive cloud instances. A high-performance Java platform is one tool in your toolbox for lowering cloud costs. Learn more in The High-Performance Java Platform Benchmark Report, available to read for free from Azul.
