HornetQ bridge throwing exceptions during performance testing

Issue

We have a HornetQ bridge configured between two nodes. We are noticing persistent CPU spikes, and a huge number of the exception below being thrown during performance testing - while messages are written to the local queue. We have observed the following WARN message :

WARN  [org.hornetq.core.server.impl.QueueImpl] (Thread-6 (HornetQ-server-HornetQServerImpl::serverUUID=e55a046a-0a3e-11e5-99c1-005056a72a85-1136091231)) Couldn't finish waiting executors. Try increasing the thread pool size
java.lang.Exception: trace
    at org.hornetq.core.server.impl.QueueImpl.flushExecutor(QueueImpl.java:560)
    at org.hornetq.core.server.impl.QueueImpl.addTail(QueueImpl.java:452)
    at org.hornetq.core.postoffice.impl.PostOfficeImpl.addReferences(PostOfficeImpl.java:1259)
    at org.hornetq.core.postoffice.impl.PostOfficeImpl.access$200(PostOfficeImpl.java:80)
    at org.hornetq.core.postoffice.impl.PostOfficeImpl$1.done(PostOfficeImpl.java:1077)
    at org.hornetq.core.persistence.impl.journal.OperationContextImpl$1.run(OperationContextImpl.java:239)
    at org.hornetq.utils.OrderedExecutorFactory$OrderedExecutor$1.run(OrderedExecutorFactory.java:100)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)