In the logs of CONTROLLER-1756 I'm seeing some of these, which should be looked at:

2017-08-22 17:11:50,048 | ERROR | Pool-1-worker-45 | DataStoreJobCoordinator | 319 - org.opendaylight.genius.mdsalutil-api - 0.2.2.Carbon | Exception when executing jobEntry: JobEntry

{key='VPNINTERFACE- 55ef861d-a228-4f3c-9b1c-110017f6604e', mainWorker=org.opendaylight.netvirt.vpnmanager.VpnInterfaceManager$$Lambda$584/679401846@6c234385, rollbackWorker=null, retryCount=0, futures=null}

java.lang.NullPointerException
at org.opendaylight.netvirt.elan.arp.responder.ArpResponderUtil.getMatchCriteria(ArpResponderUtil.java:178)
at org.opendaylight.netvirt.elan.utils.ElanUtils.addArpResponderFlow(ElanUtils.java:2333)
at org.opendaylight.netvirt.elan.internal.ElanServiceProvider.addArpResponderFlow(ElanServiceProvider.java:821)
at Proxy6027908b_d3c4_41a8_ad12_9b2b178ad779.addArpResponderFlow(Unknown Source)
at Proxy0897b899_5377_482b_9328_0843142bc04b.addArpResponderFlow(Unknown Source)
at org.opendaylight.netvirt.vpnmanager.arp.responder.ArpResponderHandler.addArpResponderFlow(ArpResponderHandler.java:95)
at org.opendaylight.netvirt.vpnmanager.VpnInterfaceManager.processVpnInterfaceAdjacencies(VpnInterfaceManager.java:633)
at org.opendaylight.netvirt.vpnmanager.VpnInterfaceManager.processVpnInterfaceUp(VpnInterfaceManager.java:354)
at org.opendaylight.netvirt.vpnmanager.VpnInterfaceManager.lambda$addVpnInterface$0(VpnInterfaceManager.java:238)
at org.opendaylight.genius.datastoreutils.DataStoreJobCoordinator$MainTask.run(DataStoreJobCoordinator.java:285)[319:org.opendaylight.genius.mdsalutil-api:0.2.2.Carbon]
at java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1402)[:1.8.0_141]
at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289)[:1.8.0_141]
at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1056)[:1.8.0_141]
at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1692)[:1.8.0_141]
at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157)[:1.8.0_141]