5
OpenJ9 Version 0.40.0 released
(eclipse.dev)
For discussing Java, the JVM, languages that run on the JVM, and other related technologies.
One would switch to a free JVM when other JVMs change their licenses from free to paid. OpenJ9 was the first free JVM to which I got introduced. Knowing it was based on the work by IBM, known for high performance and low memory footprint, it was a simple choice.