Issue

When using leveldb persistence store in ActiveMQ the store may feel when under load with

WARN | Store COMMIT FAILED: scala.MatchError: null at 

org.apache.activemq.leveldb.DelayableUOW.dequeue(DBManager.scala:282) at 
org.apache.activemq.leveldb.LevelDBStore$LevelDBMessageStore.doRemove(LevelDBStore.scala:578) at 
org.apache.activemq.leveldb.LevelDBStore$Transaction$$anon$3.commit(LevelDBStore.scala:328) at 
org.apache.activemq.leveldb.LevelDBStore$$anonfun$commit$1$$anonfun$apply$10.apply(LevelDBStore.scala:381) at 
org.apache.activemq.leveldb.LevelDBStore$$anonfun$commit$1$$anonfun$apply$10.apply(LevelDBStore.scala:380) at 
scala.collection.immutable.List.foreach(List.scala:309) at 
scala.collection.generic.TraversableForwarder$class.foreach(TraversableForwarder.scala:32) at 
scala.collection.mutable.ListBuffer.foreach(ListBuffer.scala:45) at 
org.apache.activemq.leveldb.LevelDBStore$$anonfun$commit$1.apply(LevelDBStore.scala:380) at 
org.apache.activemq.leveldb.LevelDBStore$$anonfun$commit$1.apply(LevelDBStore.scala:379) at 
org.apache.activemq.leveldb.LevelDBStore.withUow(LevelDBStore.scala:536) at 
org.apache.activemq.leveldb.LevelDBStore.commit(LevelDBStore.scala:379) at 
org.apache.activemq.transaction.LocalTransaction.commit(LocalTransaction.java:72) at 
org.apache.activemq.broker.TransactionBroker.commitTransaction(TransactionBroker.java:263) at 
org.apache.activemq.broker.MutableBrokerFilter.commitTransaction(MutableBrokerFilter.java:103) at 
org.apache.activemq.broker.TransportConnection.processCommitTransactionOnePhase(TransportConnection.java:456) at 
org.apache.activemq.command.TransactionInfo.visit(TransactionInfo.java:100) at 
org.apache.activemq.broker.TransportConnection.service(TransportConnection.java:329) at 
org.apache.activemq.broker.TransportConnection$1.onCommand(TransportConnection.java:184) at 
org.apache.activemq.transport.MutexTransport.onCommand(MutexTransport.java:50) at 
org.apache.activemq.transport.WireFormatNegotiator.onCommand(WireFormatNegotiator.java:113) at 
org.apache.activemq.transport.AbstractInactivityMonitor.onCommand(AbstractInactivityMonitor.java:288) at 
org.apache.activemq.transport.TransportSupport.doConsume(TransportSupport.java:83) at 
org.apache.activemq.transport.tcp.TcpTransport.doRun(TcpTransport.java:214) at 
org.apache.activemq.transport.tcp.TcpTransport.run(TcpTransport.java:196) at 
java.lang.Thread.run(Thread.java:722) The transaction does not exist