We had odd hangup in our SPECjvm tests with current jdk/jdk. Compiler.sunflow seems to be reliably hanging with 100% CPU active in compiled code. Bisection says it started with JDK-8192992.
Hangup seems to happen reliably with -Xmx16g -Xms16g -XX:+AlwaysPreTouch -XX:-TieredCompilation -XX:+DisableExplicitGC -XX:-UseBiasedLocking -XX:+UseParallelGC -Xlog:gc. There are no asserts in fastdebug build.