Merge "Do not use ActorSystem.actorFor as it is deprecated"
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / Shard.java
index 87a0fb931edb171ca8e2bb7d4563ff1172de4912..a30b6f7516981411e589577f3fda9a9a0f9bc887 100644 (file)
@@ -43,6 +43,8 @@ import org.opendaylight.controller.cluster.datastore.jmx.mbeans.shard.ShardStats
 import org.opendaylight.controller.cluster.datastore.messages.AbortTransaction;
 import org.opendaylight.controller.cluster.datastore.messages.AbortTransactionReply;
 import org.opendaylight.controller.cluster.datastore.messages.ActorInitialized;
+import org.opendaylight.controller.cluster.datastore.messages.BatchedModifications;
+import org.opendaylight.controller.cluster.datastore.messages.BatchedModificationsReply;
 import org.opendaylight.controller.cluster.datastore.messages.CanCommitTransaction;
 import org.opendaylight.controller.cluster.datastore.messages.CloseTransactionChain;
 import org.opendaylight.controller.cluster.datastore.messages.CommitTransaction;
@@ -60,10 +62,14 @@ import org.opendaylight.controller.cluster.datastore.messages.UpdateSchemaContex
 import org.opendaylight.controller.cluster.datastore.modification.Modification;
 import org.opendaylight.controller.cluster.datastore.modification.ModificationPayload;
 import org.opendaylight.controller.cluster.datastore.modification.MutableCompositeModification;
+import org.opendaylight.controller.cluster.datastore.utils.Dispatchers;
+import org.opendaylight.controller.cluster.datastore.utils.MessageTracker;
 import org.opendaylight.controller.cluster.datastore.utils.SerializationUtils;
+import org.opendaylight.controller.cluster.notifications.RegisterRoleChangeListener;
 import org.opendaylight.controller.cluster.notifications.RoleChangeNotifier;
 import org.opendaylight.controller.cluster.raft.RaftActor;
-import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
+import org.opendaylight.controller.cluster.raft.base.messages.FollowerInitialSyncUpStatus;
+import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.CompositeModificationByteStringPayload;
 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.CompositeModificationPayload;
 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
@@ -71,8 +77,7 @@ import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListene
 import org.opendaylight.controller.md.sal.dom.store.impl.InMemoryDOMDataStore;
 import org.opendaylight.controller.md.sal.dom.store.impl.InMemoryDOMDataStoreFactory;
 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
-import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionChain;
-import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransactionFactory;
+import org.opendaylight.controller.sal.core.spi.data.DOMStoreTransaction;
 import org.opendaylight.controller.sal.core.spi.data.DOMStoreWriteTransaction;
 import org.opendaylight.yangtools.concepts.ListenerRegistration;
 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
@@ -100,7 +105,7 @@ public class Shard extends RaftActor {
     private final InMemoryDOMDataStore store;
 
     /// The name of this shard
-    private final ShardIdentifier name;
+    private final String name;
 
     private final ShardStats shardMBean;
 
@@ -109,9 +114,9 @@ public class Shard extends RaftActor {
     private final List<DelayedListenerRegistration> delayedListenerRegistrations =
                                                                        Lists.newArrayList();
 
-    private final DatastoreContext datastoreContext;
+    private DatastoreContext datastoreContext;
 
-    private final DataPersistenceProvider dataPersistenceProvider;
+    private DataPersistenceProvider dataPersistenceProvider;
 
     private SchemaContext schemaContext;
 
@@ -119,29 +124,40 @@ public class Shard extends RaftActor {
 
     private final ShardCommitCoordinator commitCoordinator;
 
-    private final long transactionCommitTimeout;
+    private long transactionCommitTimeout;
 
     private Cancellable txCommitTimeoutCheckSchedule;
 
     private final Optional<ActorRef> roleChangeNotifier;
 
+    private final MessageTracker appendEntriesReplyTracker;
+
+    private final ReadyTransactionReply READY_TRANSACTION_REPLY = new ReadyTransactionReply(
+            Serialization.serializedActorPath(getSelf()));
+
+
     /**
      * Coordinates persistence recovery on startup.
      */
     private ShardRecoveryCoordinator recoveryCoordinator;
     private List<Object> currentLogRecoveryBatch;
 
-    private final Map<String, DOMStoreTransactionChain> transactionChains = new HashMap<>();
+    private final DOMTransactionFactory transactionFactory;
 
-    protected Shard(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
+    private final String txnDispatcherPath;
+
+    protected Shard(final ShardIdentifier name, final Map<String, String> peerAddresses,
             final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
-        super(name.toString(), mapPeerAddresses(peerAddresses),
-                Optional.of(datastoreContext.getShardRaftConfig()));
+        super(name.toString(), new HashMap<>(peerAddresses), Optional.of(datastoreContext.getShardRaftConfig()));
 
-        this.name = name;
+        this.name = name.toString();
         this.datastoreContext = datastoreContext;
         this.schemaContext = schemaContext;
-        this.dataPersistenceProvider = (datastoreContext.isPersistent()) ? new PersistentDataProvider() : new NonPersistentRaftDataProvider();
+        this.dataPersistenceProvider = (datastoreContext.isPersistent())
+                ? new PersistentDataProvider() : new NonPersistentRaftDataProvider();
+        this.txnDispatcherPath = new Dispatchers(context().system().dispatchers())
+                .getDispatcherPath(Dispatchers.DispatcherType.Transaction);
+
 
         LOG.info("Shard created : {}, persistent : {}", name, datastoreContext.isPersistent());
 
@@ -155,35 +171,34 @@ public class Shard extends RaftActor {
         shardMBean = ShardMBeanFactory.getShardStatsMBean(name.toString(),
                 datastoreContext.getDataStoreMXBeanType());
         shardMBean.setNotificationManager(store.getDataChangeListenerNotificationManager());
+        shardMBean.setShardActor(getSelf());
 
         if (isMetricsCaptureEnabled()) {
             getContext().become(new MeteringBehavior(this));
         }
 
-        commitCoordinator = new ShardCommitCoordinator(TimeUnit.SECONDS.convert(1, TimeUnit.MINUTES),
-                datastoreContext.getShardTransactionCommitQueueCapacity(), LOG, name.toString());
+        transactionFactory = new DOMTransactionFactory(store, shardMBean, LOG, this.name);
 
-        transactionCommitTimeout = TimeUnit.MILLISECONDS.convert(
-                datastoreContext.getShardTransactionCommitTimeoutInSeconds(), TimeUnit.SECONDS);
+        commitCoordinator = new ShardCommitCoordinator(transactionFactory,
+                TimeUnit.SECONDS.convert(5, TimeUnit.MINUTES),
+                datastoreContext.getShardTransactionCommitQueueCapacity(), self(), LOG, this.name);
+
+        setTransactionCommitTimeout();
 
         // create a notifier actor for each cluster member
         roleChangeNotifier = createRoleChangeNotifier(name.toString());
-    }
 
-    private static Map<String, String> mapPeerAddresses(
-        final Map<ShardIdentifier, String> peerAddresses) {
-        Map<String, String> map = new HashMap<>();
-
-        for (Map.Entry<ShardIdentifier, String> entry : peerAddresses
-            .entrySet()) {
-            map.put(entry.getKey().toString(), entry.getValue());
-        }
+        appendEntriesReplyTracker = new MessageTracker(AppendEntriesReply.class,
+                getRaftActorContext().getConfigParams().getIsolatedCheckIntervalInMillis());
+    }
 
-        return map;
+    private void setTransactionCommitTimeout() {
+        transactionCommitTimeout = TimeUnit.MILLISECONDS.convert(
+                datastoreContext.getShardTransactionCommitTimeoutInSeconds(), TimeUnit.SECONDS);
     }
 
     public static Props props(final ShardIdentifier name,
-        final Map<ShardIdentifier, String> peerAddresses,
+        final Map<String, String> peerAddresses,
         final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
         Preconditions.checkNotNull(name, "name should not be null");
         Preconditions.checkNotNull(peerAddresses, "peerAddresses should not be null");
@@ -196,16 +211,20 @@ public class Shard extends RaftActor {
     private Optional<ActorRef> createRoleChangeNotifier(String shardId) {
         ActorRef shardRoleChangeNotifier = this.getContext().actorOf(
             RoleChangeNotifier.getProps(shardId), shardId + "-notifier");
-        return Optional.<ActorRef>of(shardRoleChangeNotifier);
+        return Optional.of(shardRoleChangeNotifier);
     }
 
     @Override
     public void postStop() {
+        LOG.info("Stopping Shard {}", persistenceId());
+
         super.postStop();
 
         if(txCommitTimeoutCheckSchedule != null) {
             txCommitTimeoutCheckSchedule.cancel();
         }
+
+        shardMBean.unregisterMBean();
     }
 
     @Override
@@ -224,39 +243,59 @@ public class Shard extends RaftActor {
             onRecoveryComplete();
         } else {
             super.onReceiveRecover(message);
+            if(LOG.isTraceEnabled()) {
+                appendEntriesReplyTracker.begin();
+            }
         }
     }
 
     @Override
     public void onReceiveCommand(final Object message) throws Exception {
-        if(LOG.isDebugEnabled()) {
-            LOG.debug("{}: onReceiveCommand: Received message {} from {}", persistenceId(), message, getSender());
-        }
-
-        if (message.getClass().equals(CreateTransaction.SERIALIZABLE_CLASS)) {
-            handleCreateTransaction(message);
-        } else if(message instanceof ForwardedReadyTransaction) {
-            handleForwardedReadyTransaction((ForwardedReadyTransaction)message);
-        } else if(message.getClass().equals(CanCommitTransaction.SERIALIZABLE_CLASS)) {
-            handleCanCommitTransaction(CanCommitTransaction.fromSerializable(message));
-        } else if(message.getClass().equals(CommitTransaction.SERIALIZABLE_CLASS)) {
-            handleCommitTransaction(CommitTransaction.fromSerializable(message));
-        } else if(message.getClass().equals(AbortTransaction.SERIALIZABLE_CLASS)) {
-            handleAbortTransaction(AbortTransaction.fromSerializable(message));
-        } else if (message.getClass().equals(CloseTransactionChain.SERIALIZABLE_CLASS)){
-            closeTransactionChain(CloseTransactionChain.fromSerializable(message));
-        } else if (message instanceof RegisterChangeListener) {
-            registerChangeListener((RegisterChangeListener) message);
-        } else if (message instanceof UpdateSchemaContext) {
-            updateSchemaContext((UpdateSchemaContext) message);
-        } else if (message instanceof PeerAddressResolved) {
-            PeerAddressResolved resolved = (PeerAddressResolved) message;
-            setPeerAddress(resolved.getPeerId().toString(),
-                resolved.getPeerAddress());
-        } else if(message.equals(TX_COMMIT_TIMEOUT_CHECK_MESSAGE)) {
-            handleTransactionCommitTimeoutCheck();
-        } else {
-            super.onReceiveCommand(message);
+
+        MessageTracker.Context context = appendEntriesReplyTracker.received(message);
+
+        if(context.error().isPresent()){
+            LOG.trace("{} : AppendEntriesReply failed to arrive at the expected interval {}", persistenceId(),
+                    context.error());
+        }
+
+        try {
+            if (CreateTransaction.SERIALIZABLE_CLASS.isInstance(message)) {
+                handleCreateTransaction(message);
+            } else if (BatchedModifications.class.isInstance(message)) {
+                handleBatchedModifications((BatchedModifications)message);
+            } else if (message instanceof ForwardedReadyTransaction) {
+                handleForwardedReadyTransaction((ForwardedReadyTransaction) message);
+            } else if (CanCommitTransaction.SERIALIZABLE_CLASS.isInstance(message)) {
+                handleCanCommitTransaction(CanCommitTransaction.fromSerializable(message));
+            } else if (CommitTransaction.SERIALIZABLE_CLASS.isInstance(message)) {
+                handleCommitTransaction(CommitTransaction.fromSerializable(message));
+            } else if (AbortTransaction.SERIALIZABLE_CLASS.isInstance(message)) {
+                handleAbortTransaction(AbortTransaction.fromSerializable(message));
+            } else if (CloseTransactionChain.SERIALIZABLE_CLASS.isInstance(message)) {
+                closeTransactionChain(CloseTransactionChain.fromSerializable(message));
+            } else if (message instanceof RegisterChangeListener) {
+                registerChangeListener((RegisterChangeListener) message);
+            } else if (message instanceof UpdateSchemaContext) {
+                updateSchemaContext((UpdateSchemaContext) message);
+            } else if (message instanceof PeerAddressResolved) {
+                PeerAddressResolved resolved = (PeerAddressResolved) message;
+                setPeerAddress(resolved.getPeerId().toString(),
+                        resolved.getPeerAddress());
+            } else if (message.equals(TX_COMMIT_TIMEOUT_CHECK_MESSAGE)) {
+                handleTransactionCommitTimeoutCheck();
+            } else if(message instanceof DatastoreContext) {
+                onDatastoreContext((DatastoreContext)message);
+            } else if(message instanceof RegisterRoleChangeListener){
+                roleChangeNotifier.get().forward(message, context());
+            } else if (message instanceof FollowerInitialSyncUpStatus){
+                shardMBean.setFollowerInitialSyncStatus(((FollowerInitialSyncUpStatus) message).isInitialSyncDone());
+                context().parent().tell(message, self());
+            } else {
+                super.onReceiveCommand(message);
+            }
+        } finally {
+            context.done();
         }
     }
 
@@ -265,6 +304,24 @@ public class Shard extends RaftActor {
         return roleChangeNotifier;
     }
 
+    private void onDatastoreContext(DatastoreContext context) {
+        datastoreContext = context;
+
+        commitCoordinator.setQueueCapacity(datastoreContext.getShardTransactionCommitQueueCapacity());
+
+        setTransactionCommitTimeout();
+
+        if(datastoreContext.isPersistent() &&
+                dataPersistenceProvider instanceof NonPersistentRaftDataProvider) {
+            dataPersistenceProvider = new PersistentDataProvider();
+        } else if(!datastoreContext.isPersistent() &&
+                dataPersistenceProvider instanceof PersistentDataProvider) {
+            dataPersistenceProvider = new NonPersistentRaftDataProvider();
+        }
+
+        updateConfigParams(datastoreContext.getShardRaftConfig());
+    }
+
     private void handleTransactionCommitTimeoutCheck() {
         CohortEntry cohortEntry = commitCoordinator.getCurrentCohortEntry();
         if(cohortEntry != null) {
@@ -309,9 +366,10 @@ public class Shard extends RaftActor {
             // currently uses a same thread executor anyway.
             cohortEntry.getCohort().preCommit().get();
 
-            // If we do not have any followers and we are not using persistence we can
-            // apply modification to the state immediately
-            if(!hasFollowers() && !persistence().isRecoveryApplicable()){
+            // If we do not have any followers and we are not using persistence
+            // or if cohortEntry has no modifications
+            // we can apply modification to the state immediately
+            if((!hasFollowers() && !persistence().isRecoveryApplicable()) || (!cohortEntry.hasModifications())){
                 applyModificationToState(getSender(), transactionID, cohortEntry.getModification());
             } else {
                 Shard.this.persistData(getSender(), transactionID,
@@ -385,6 +443,47 @@ public class Shard extends RaftActor {
         commitCoordinator.handleCanCommit(canCommit, getSender(), self());
     }
 
+    private void handleBatchedModifications(BatchedModifications batched) {
+        // This message is sent to prepare the modificationsa transaction directly on the Shard as an
+        // optimization to avoid the extra overhead of a separate ShardTransaction actor. On the last
+        // BatchedModifications message, the caller sets the ready flag in the message indicating
+        // modifications are complete. The reply contains the cohort actor path (this actor) for the caller
+        // to initiate the 3-phase commit. This also avoids the overhead of sending an additional
+        // ReadyTransaction message.
+
+        // If we're not the leader then forward to the leader. This is a safety measure - we shouldn't
+        // normally get here if we're not the leader as the front-end (TransactionProxy) should determine
+        // the primary/leader shard. However with timing and caching on the front-end, there's a small
+        // window where it could have a stale leader during leadership transitions.
+        //
+        if(isLeader()) {
+            try {
+                BatchedModificationsReply reply = commitCoordinator.handleTransactionModifications(batched);
+                sender().tell(reply, self());
+            } catch (Exception e) {
+                LOG.error("{}: Error handling BatchedModifications for Tx {}", persistenceId(),
+                        batched.getTransactionID(), e);
+                getSender().tell(new akka.actor.Status.Failure(e), getSelf());
+            }
+        } else {
+            ActorSelection leader = getLeader();
+            if(leader != null) {
+                // TODO: what if this is not the first batch and leadership changed in between batched messages?
+                // We could check if the commitCoordinator already has a cached entry and forward all the previous
+                // batched modifications.
+                LOG.debug("{}: Forwarding BatchedModifications to leader {}", persistenceId(), leader);
+                leader.forward(batched, getContext());
+            } else {
+                // TODO: rather than throwing an immediate exception, we could schedule a timer to try again to make
+                // it more resilient in case we're in the process of electing a new leader.
+                getSender().tell(new akka.actor.Status.Failure(new NoShardLeaderException(String.format(
+                    "Could not find the leader for shard %s. This typically happens" +
+                    " when the system is coming up or recovering and a leader is being elected. Try again" +
+                    " later.", persistenceId()))), getSelf());
+            }
+        }
+    }
+
     private void handleForwardedReadyTransaction(ForwardedReadyTransaction ready) {
         LOG.debug("{}: Readying transaction {}, client version {}", persistenceId(),
                 ready.getTransactionID(), ready.getTxnClientVersion());
@@ -393,24 +492,28 @@ public class Shard extends RaftActor {
         // commitCoordinator in preparation for the subsequent three phase commit initiated by
         // the front-end.
         commitCoordinator.transactionReady(ready.getTransactionID(), ready.getCohort(),
-                ready.getModification());
+                (MutableCompositeModification) ready.getModification());
 
         // Return our actor path as we'll handle the three phase commit, except if the Tx client
         // version < 1 (Helium-1 version). This means the Tx was initiated by a base Helium version
         // node. In that case, the subsequent 3-phase commit messages won't contain the
         // transactionId so to maintain backwards compatibility, we create a separate cohort actor
         // to provide the compatible behavior.
-        ActorRef replyActorPath = self();
         if(ready.getTxnClientVersion() < DataStoreVersions.HELIUM_1_VERSION) {
             LOG.debug("{}: Creating BackwardsCompatibleThreePhaseCommitCohort", persistenceId());
-            replyActorPath = getContext().actorOf(BackwardsCompatibleThreePhaseCommitCohort.props(
+            ActorRef replyActorPath = getContext().actorOf(BackwardsCompatibleThreePhaseCommitCohort.props(
                     ready.getTransactionID()));
-        }
 
-        ReadyTransactionReply readyTransactionReply = new ReadyTransactionReply(
-                Serialization.serializedActorPath(replyActorPath));
-        getSender().tell(ready.isReturnSerialized() ? readyTransactionReply.toSerializable() :
-                readyTransactionReply, getSelf());
+            ReadyTransactionReply readyTransactionReply =
+                    new ReadyTransactionReply(Serialization.serializedActorPath(replyActorPath));
+            getSender().tell(ready.isReturnSerialized() ? readyTransactionReply.toSerializable() :
+                    readyTransactionReply, getSelf());
+
+        } else {
+
+            getSender().tell(ready.isReturnSerialized() ? READY_TRANSACTION_REPLY.toSerializable() :
+                    READY_TRANSACTION_REPLY, getSelf());
+        }
     }
 
     private void handleAbortTransaction(final AbortTransaction abort) {
@@ -466,68 +569,29 @@ public class Shard extends RaftActor {
     }
 
     private void closeTransactionChain(final CloseTransactionChain closeTransactionChain) {
-        DOMStoreTransactionChain chain =
-            transactionChains.remove(closeTransactionChain.getTransactionChainId());
-
-        if(chain != null) {
-            chain.close();
-        }
+        transactionFactory.closeTransactionChain(closeTransactionChain.getTransactionChainId());
     }
 
     private ActorRef createTypedTransactionActor(int transactionType,
             ShardTransactionIdentifier transactionId, String transactionChainId,
             short clientVersion ) {
 
-        DOMStoreTransactionFactory factory = store;
+        DOMStoreTransaction transaction = transactionFactory.newTransaction(
+                TransactionProxy.TransactionType.fromInt(transactionType), transactionId.toString(),
+                transactionChainId);
 
-        if(!transactionChainId.isEmpty()) {
-            factory = transactionChains.get(transactionChainId);
-            if(factory == null){
-                DOMStoreTransactionChain transactionChain = store.createTransactionChain();
-                transactionChains.put(transactionChainId, transactionChain);
-                factory = transactionChain;
-            }
-        }
-
-        if(this.schemaContext == null) {
-            throw new IllegalStateException("SchemaContext is not set");
-        }
-
-        if (transactionType == TransactionProxy.TransactionType.READ_ONLY.ordinal()) {
-
-            shardMBean.incrementReadOnlyTransactionCount();
-
-            return getContext().actorOf(
-                ShardTransaction.props(factory.newReadOnlyTransaction(), getSelf(),
-                        schemaContext,datastoreContext, shardMBean,
-                        transactionId.getRemoteTransactionId(), clientVersion),
-                        transactionId.toString());
-
-        } else if (transactionType == TransactionProxy.TransactionType.READ_WRITE.ordinal()) {
-
-            shardMBean.incrementReadWriteTransactionCount();
+        return createShardTransaction(transaction, transactionId, clientVersion);
+    }
 
-            return getContext().actorOf(
-                ShardTransaction.props(factory.newReadWriteTransaction(), getSelf(),
+    private ActorRef createShardTransaction(DOMStoreTransaction transaction, ShardTransactionIdentifier transactionId,
+                                            short clientVersion){
+        return getContext().actorOf(
+                ShardTransaction.props(transaction, getSelf(),
                         schemaContext, datastoreContext, shardMBean,
-                        transactionId.getRemoteTransactionId(), clientVersion),
-                        transactionId.toString());
-
-
-        } else if (transactionType == TransactionProxy.TransactionType.WRITE_ONLY.ordinal()) {
+                        transactionId.getRemoteTransactionId(), clientVersion)
+                        .withDispatcher(txnDispatcherPath),
+                transactionId.toString());
 
-            shardMBean.incrementWriteOnlyTransactionCount();
-
-            return getContext().actorOf(
-                ShardTransaction.props(factory.newWriteOnlyTransaction(), getSelf(),
-                        schemaContext, datastoreContext, shardMBean,
-                        transactionId.getRemoteTransactionId(), clientVersion),
-                        transactionId.toString());
-        } else {
-            throw new IllegalArgumentException(
-                "Shard="+name + ":CreateTransaction message has unidentified transaction type="
-                    + transactionType);
-        }
     }
 
     private void createTransaction(CreateTransaction createTransaction) {
@@ -546,10 +610,8 @@ public class Shard extends RaftActor {
     private ActorRef createTransaction(int transactionType, String remoteTransactionId,
             String transactionChainId, short clientVersion) {
 
-        ShardTransactionIdentifier transactionId =
-            ShardTransactionIdentifier.builder()
-                .remoteTransactionId(remoteTransactionId)
-                .build();
+
+        ShardTransactionIdentifier transactionId = new ShardTransactionIdentifier(remoteTransactionId);
 
         if(LOG.isDebugEnabled()) {
             LOG.debug("{}: Creating transaction : {} ", persistenceId(), transactionId);
@@ -615,7 +677,7 @@ public class Shard extends RaftActor {
         LOG.debug("{}: registerDataChangeListener sending reply, listenerRegistrationPath = {} ",
                 persistenceId(), listenerRegistration.path());
 
-        getSender().tell(new RegisterChangeListenerReply(listenerRegistration.path()), getSelf());
+        getSender().tell(new RegisterChangeListenerReply(listenerRegistration), getSelf());
     }
 
     private ListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
@@ -726,7 +788,6 @@ public class Shard extends RaftActor {
 
         recoveryCoordinator = null;
         currentLogRecoveryBatch = null;
-        updateJournalStats();
 
         //notify shard manager
         getContext().parent().tell(new ActorInitialized(), getSelf());
@@ -765,9 +826,6 @@ public class Shard extends RaftActor {
                     persistenceId(), data, data.getClass().getClassLoader(),
                     CompositeModificationPayload.class.getClassLoader());
         }
-
-        updateJournalStats();
-
     }
 
     private void applyModificationToState(ActorRef clientActor, String identifier, Object modification) {
@@ -785,19 +843,6 @@ public class Shard extends RaftActor {
         }
     }
 
-    private void updateJournalStats() {
-        ReplicatedLogEntry lastLogEntry = getLastLogEntry();
-
-        if (lastLogEntry != null) {
-            shardMBean.setLastLogIndex(lastLogEntry.getIndex());
-            shardMBean.setLastLogTerm(lastLogEntry.getTerm());
-        }
-
-        shardMBean.setCommitIndex(getCommitIndex());
-        shardMBean.setLastApplied(getLastApplied());
-        shardMBean.setInMemoryJournalDataSize(getRaftActorContext().getReplicatedLog().dataSize());
-    }
-
     @Override
     protected void createSnapshot() {
         // Create a transaction actor. We are really going to treat the transaction as a worker
@@ -855,21 +900,15 @@ public class Shard extends RaftActor {
             delayedListenerRegistrations.clear();
         }
 
-        shardMBean.setRaftState(getRaftState().name());
-        shardMBean.setCurrentTerm(getCurrentTerm());
-
         // If this actor is no longer the leader close all the transaction chains
-        if(!isLeader){
-            for(Map.Entry<String, DOMStoreTransactionChain> entry : transactionChains.entrySet()){
-                if(LOG.isDebugEnabled()) {
-                    LOG.debug(
-                        "{}: onStateChanged: Closing transaction chain {} because shard {} is no longer the leader",
-                        persistenceId(), entry.getKey(), getId());
-                }
-                entry.getValue().close();
+        if(!isLeader) {
+            if(LOG.isDebugEnabled()) {
+                LOG.debug(
+                    "{}: onStateChanged: Closing all transaction chains because shard {} is no longer the leader",
+                    persistenceId(), getId());
             }
 
-            transactionChains.clear();
+            transactionFactory.closeAllTransactionChains();
         }
     }
 
@@ -878,12 +917,8 @@ public class Shard extends RaftActor {
         return dataPersistenceProvider;
     }
 
-    @Override protected void onLeaderChanged(final String oldLeader, final String newLeader) {
-        shardMBean.setLeader(newLeader);
-    }
-
     @Override public String persistenceId() {
-        return this.name.toString();
+        return this.name;
     }
 
     @VisibleForTesting
@@ -891,16 +926,22 @@ public class Shard extends RaftActor {
         return dataPersistenceProvider;
     }
 
+    @VisibleForTesting
+    ShardCommitCoordinator getCommitCoordinator() {
+        return commitCoordinator;
+    }
+
+
     private static class ShardCreator implements Creator<Shard> {
 
         private static final long serialVersionUID = 1L;
 
         final ShardIdentifier name;
-        final Map<ShardIdentifier, String> peerAddresses;
+        final Map<String, String> peerAddresses;
         final DatastoreContext datastoreContext;
         final SchemaContext schemaContext;
 
-        ShardCreator(final ShardIdentifier name, final Map<ShardIdentifier, String> peerAddresses,
+        ShardCreator(final ShardIdentifier name, final Map<String, String> peerAddresses,
                 final DatastoreContext datastoreContext, final SchemaContext schemaContext) {
             this.name = name;
             this.peerAddresses = peerAddresses;
@@ -915,7 +956,7 @@ public class Shard extends RaftActor {
     }
 
     @VisibleForTesting
-    InMemoryDOMDataStore getDataStore() {
+    public InMemoryDOMDataStore getDataStore() {
         return store;
     }