Comment by MaxBarraclough

Neat to see sleep calls artificially introduced to reliably recreate the deadlock. [0]

Looks like fixing the underlying bug is still in-progress, [1] I wonder how many lines of code it will take.

[0] https://github.com/aoli-al/jdk/commit/625420ba82d2b0ebac24d9...

[1] https://bugs.openjdk.org/browse/JDK-8358601