Sumatra is planned for integration latest by Java 10.
There were a few Java ONE 2014 and JVM Language Summit Presentations.
JRuby: The Hard Parts, Reduction on GPUs, GPU/JVM Cooperation
http://www.oracle.com/technetwork/java/javase/community/jlss...
Ruby on Top of Graal
https://old.parleys.com/share_channel.html#play/543f88bee4b0...
Sumatra OpenJDK Project Update: Parallelize Yourself with the Stream API
https://old.parleys.com/share_channel.html#play/543fa782e4b0...