Running demos occasionally yields:

Exception in thread "Read thread for localhost/127.0.0.1:9999" java.util.concurrent.RejectedExecutionException
at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:1768)
at java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:767)
at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:658)
at org.jboss.as.protocol.ConnectionImpl$1.run(ConnectionImpl.java:211)
at java.lang.Thread.run(Thread.java:662)

The created executors should most likely have a rejection policy of CallerRuns, and probably a longer queue.