Java 21 to 25: Key Performance & Runtime Updates 🚀

Every release of Java includes performance and runtime updates. For organizations moving from Java 21 to 25, that means a lot of release notes to review to understand all that has changed. Luckily Billy Korando from ACME Soft has already done all the work of breaking down the important performance and runtime updates. Join Billy as he covers the key updates you need to know about; including Compact Object Headers, ZGC and JFR updates, and more!

JDK 25: https://jdk.java.net/25/
Java 25 Launch Stream: https://dev.java/community/java-25-launch/
ACME Soft's Road to 25: https://www.youtube.com/playlist?list=PLX8CzqL3ArzXJ2_0FIGleUisXuUm4AESE

~~~~~ Chapters ~~~~~

0:00 Intro
* https://netflixtechblog.com/java-21-virtual-threads-dude-wheres-my-lock-3052540e231d?gi=93ce375c67fe

1:56 Performance Updates
* https://inside.java/2025/05/01/strings-just-got-faster/
* https://inside.java/2025/03/19/performance-improvements-in-jdk24/
* https://youtu.be/LXWbyf8SUjI

6:23 Compact Object Headers
* https://openjdk.org/jeps/519
* https://openjdk.org/projects/lilliput/
* https://openjdk.org/jeps/450
* https://openjdk.org/jeps/503
* https://cr.openjdk.org/~skuksenko/jep519/performance.txt

8:21 ZGC Updates
* https://openjdk.org/jeps/439
* https://openjdk.org/jeps/474
* https://openjdk.org/jeps/490

9:18 JFR Updates
* https://openjdk.org/jeps/518
* https://openjdk.org/jeps/520
* https://www.youtube.com/watch?v=AgFOJEkBVjg

16:38 Outro

Tags: #Java #Java25 #Performance #OpenJDK