Diffa Diffa

If the writer proxy in the PairActor times out, you see the following stack trace:

09:21:20.474 [akka:event-driven:dispatcher:global-6] ERROR PairActor:252 - Downstream scan failed: xxx
java.util.NoSuchElementException: None.get
        at scala.None$.get(Option.scala:275) ~[scala-library-2.9.0-1.jar:na]
        at scala.None$.get(Option.scala:273) ~[scala-library-2.9.0-1.jar:na]
        at net.lshift.diffa.kernel.actors.PairActor$$anon$1.get(PairActor.scala:95) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.actors.PairActor$$anon$1.storeDownstreamVersion(PairActor.scala:92) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.differencing.SameVersionPolicy$DownstreamSameSyncStrategy.handleMismatch(SameVersionPolicy.scala:55) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy$$anonfun$scanParticipant$1$$anonfun$apply$1.apply(BaseSynchingVersionPolicy.scala:139) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy$$anonfun$scanParticipant$1$$anonfun$apply$1.apply(BaseSynchingVersionPolicy.scala:139) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]        at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:59) ~[scala-library-2.9.0-1.jar:na]
        at scala.collection.immutable.List.foreach(List.scala:45) ~[scala-library-2.9.0-1.jar:na]        at scala.collection.generic.TraversableForwarder$class.foreach(TraversableForwarder.scala:30) ~[scala-library-2.9.0-1.jar:na]        at scala.collection.mutable.ListBuffer.foreach(ListBuffer.scala:42) ~[scala-library-2.9.0-1.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy$$anonfun$scanParticipant$1.apply(BaseSynchingVersionPolicy.scala:139) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy$$anonfun$scanParticipant$1.apply(BaseSynchingVersionPolicy.scala:126) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:59) ~[scala-library-2.9.0-1.jar:na]        at scala.collection.immutable.List.foreach(List.scala:45) ~[scala-library-2.9.0-1.jar:na]        at scala.collection.generic.TraversableForwarder$class.foreach(TraversableForwarder.scala:30) ~[scala-library-2
.9.0-1.jar:na]        at scala.collection.mutable.ListBuffer.foreach(ListBuffer.scala:42) ~[scala-library-2.9.0-1.jar:na]        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy.scanParticipant(BaseSynchingVersionPolicy.scala:126) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$$anonfun$scanDownstream$1.apply(BaseSynchingVersionPolicy.scala:87) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$$anonfun$scanDownstream$1.apply(BaseSynchingVersionPolicy.scala:87) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:60) ~[scala-library-2.9.0-1.jar:na]        at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:44) ~[scala-library-2.9.0-1.jar:na]
at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy.scanDownstream(BaseSynchingVersionPolicy.scala:87) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.actors.PairActor$$anonfun$handleScanMessage$2.apply$mcV$sp(PairActor.scala:247) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at akka.actor.Actor$$anon$1$$anonfun$receive$1.apply(Actor.scala:232) [akka-actor-1.1.2.jar:na]
        at akka.actor.Actor$$anon$1$$anonfun$receive$1.apply(Actor.scala:231) [akka-actor-1.1.2.jar:na]
        at akka.actor.Actor$class.apply(Actor.scala:476) [akka-actor-1.1.2.jar:na]
        at akka.actor.Actor$$anon$1.apply(Actor.scala:229) [akka-actor-1.1.2.jar:na]
        at akka.actor.LocalActorRef.invoke(ActorRef.scala:861) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.MessageInvocation.invoke(MessageHandling.scala:26) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.ExecutableMailbox$class.processMailbox(ExecutorBasedEventDrivenDispatcher.scala:209) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.ExecutorBasedEventDrivenDispatcher$$anon$4.processMailbox(ExecutorBasedEventDrivenDispatcher.scala:120) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.ExecutableMailbox$class.run(ExecutorBasedEventDrivenDispatcher.scala:182) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.ExecutorBasedEventDrivenDispatcher$$anon$4.run(ExecutorBasedEventDrivenDispatcher.scala:120) [akka-actor-1.1.2.jar:na]
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) [na:1.6.0_24]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) [na:1.6.0_24]
        at java.lang.Thread.run(Thread.java:662) [na:1.6.0_24]
        at akka.dispatch.MonitorableThread.run(ThreadPoolBuilder.scala:182) [akka-actor-1.1.2.jar:na]
09:21:20.907 [akka:event-driven:dispatcher:global-3] ERROR PairActor:128 - Received scan failure: 36be76a0-91a8-11e0-86cb-005056a80146
09:21:20.907 [akka:event-driven:dispatcher:global-3] INFO DefaultSessionManager:433 - Pair Staging4 entered synchronization state: FAILED

This is followed by:

09:21:47.987 [akka:event-driven:dispatcher:global-16] ERROR PairActor:140 - D1: Received command (VersionCorrelationWriterCommand(36be76a0-91a8-11e0-86cb-005056a80146,<function1>)) in non-scanning state - potential bug
09:21:52.988 [akka:event-driven:dispatcher:global-5] ERROR PairActor:239 - Upstream scan failed: xxx
java.util.NoSuchElementException: None.get
        at scala.None$.get(Option.scala:275) ~[scala-library-2.9.0-1.jar:na]
        at scala.None$.get(Option.scala:273) ~[scala-library-2.9.0-1.jar:na]
        at net.lshift.diffa.kernel.actors.PairActor$$anon$1.get(PairActor.scala:95) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.actors.PairActor$$anon$1.storeUpstreamVersion(PairActor.scala:94) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$UpstreamSyncStrategy.handleMismatch(BaseSynchingVersionPolicy.scala:179) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy$$anonfun$scanParticipant$1$$anonfun$apply$1.apply(BaseSynchingVersionPolicy.scala:139) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy$$anonfun$scanParticipant$1$$anonfun$apply$1.apply(BaseSynchingVersionPolicy.scala:139) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:59) ~[scala-library-2.9.0-1.jar:na]
        at scala.collection.immutable.List.foreach(List.scala:45) ~[scala-library-2.9.0-1.jar:na]
        at scala.collection.generic.TraversableForwarder$class.foreach(TraversableForwarder.scala:30) ~[scala-library-2.9.0-1.jar:na]
        at scala.collection.mutable.ListBuffer.foreach(ListBuffer.scala:42) ~[scala-library-2.9.0-1.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy$$anonfun$scanParticipant$1.apply(BaseSynchingVersionPolicy.scala:139) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy$$anonfun$scanParticipant$1.apply(BaseSynchingVersionPolicy.scala:126) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:59) ~[scala-library-2.9.0-1.jar:na]
        at scala.collection.immutable.List.foreach(List.scala:45) ~[scala-library-2.9.0-1.jar:na]
        at scala.collection.generic.TraversableForwarder$class.foreach(TraversableForwarder.scala:30) ~[scala-library-2.9.0-1.jar:na]
        at scala.collection.mutable.ListBuffer.foreach(ListBuffer.scala:42) ~[scala-library-2.9.0-1.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$SyncStrategy.scanParticipant(BaseSynchingVersionPolicy.scala:126) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$$anonfun$scanUpstream$1.apply(BaseSynchingVersionPolicy.scala:81) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy$$anonfun$scanUpstream$1.apply(BaseSynchingVersionPolicy.scala:81) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:60) ~[scala-library-2.9.0-1.jar:na]
        at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:44) ~[scala-library-2.9.0-1.jar:na]
        at net.lshift.diffa.kernel.differencing.BaseSynchingVersionPolicy.scanUpstream(BaseSynchingVersionPolicy.scala:81) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at net.lshift.diffa.kernel.actors.PairActor$$anonfun$handleScanMessage$1.apply$mcV$sp(PairActor.scala:234) ~[diffa-kernel-0.9-SNAPSHOT.jar:na]
        at akka.actor.Actor$$anon$1$$anonfun$receive$1.apply(Actor.scala:232) [akka-actor-1.1.2.jar:na]
        at akka.actor.Actor$$anon$1$$anonfun$receive$1.apply(Actor.scala:231) [akka-actor-1.1.2.jar:na]
at akka.actor.Actor$$anon$1$$anonfun$receive$1.apply(Actor.scala:231) [akka-actor-1.1.2.jar:na]
        at akka.actor.Actor$class.apply(Actor.scala:476) [akka-actor-1.1.2.jar:na]
        at akka.actor.Actor$$anon$1.apply(Actor.scala:229) [akka-actor-1.1.2.jar:na]
        at akka.actor.LocalActorRef.invoke(ActorRef.scala:861) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.MessageInvocation.invoke(MessageHandling.scala:26) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.ExecutableMailbox$class.processMailbox(ExecutorBasedEventDrivenDispatcher.scala:209) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.ExecutorBasedEventDrivenDispatcher$$anon$4.processMailbox(ExecutorBasedEventDrivenDispatcher.scala:120) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.ExecutableMailbox$class.run(ExecutorBasedEventDrivenDispatcher.scala:182) [akka-actor-1.1.2.jar:na]
        at akka.dispatch.ExecutorBasedEventDrivenDispatcher$$anon$4.run(ExecutorBasedEventDrivenDispatcher.scala:120) [akka-actor-1.1.2.jar:na]
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) [na:1.6.0_24]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) [na:1.6.0_24]
        at java.lang.Thread.run(Thread.java:662) [na:1.6.0_24]
        at akka.dispatch.MonitorableThread.run(ThreadPoolBuilder.scala:182) [akka-actor-1.1.2.jar:na]
09:21:52.990 [akka:event-driven:dispatcher:global-2] ERROR PairActor:144 - D1: Received scan failure (36be76a0-91a8-11e0-86cb-005056a80146) in non-scanning state - potential bug