import akka.persistence.SnapshotOffer;
import akka.persistence.SnapshotSelectionCriteria;
import akka.persistence.UntypedPersistentActor;
+import com.google.common.base.Optional;
+import com.google.protobuf.ByteString;
import org.opendaylight.controller.cluster.raft.base.messages.ApplySnapshot;
import org.opendaylight.controller.cluster.raft.base.messages.ApplyState;
+import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshot;
+import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshotReply;
import org.opendaylight.controller.cluster.raft.base.messages.Replicate;
+import org.opendaylight.controller.cluster.raft.base.messages.SendHeartBeat;
import org.opendaylight.controller.cluster.raft.behaviors.Candidate;
import org.opendaylight.controller.cluster.raft.behaviors.Follower;
import org.opendaylight.controller.cluster.raft.behaviors.Leader;
import org.opendaylight.controller.cluster.raft.client.messages.FindLeader;
import org.opendaylight.controller.cluster.raft.client.messages.FindLeaderReply;
import org.opendaylight.controller.cluster.raft.client.messages.RemoveRaftPeer;
+import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
+import org.opendaylight.controller.protobuff.messages.cluster.raft.AppendEntriesMessages;
import java.io.Serializable;
-import java.util.ArrayList;
-import java.util.List;
import java.util.Map;
/**
*/
private ReplicatedLogImpl replicatedLog = new ReplicatedLogImpl();
+ private CaptureSnapshot captureSnapshot = null;
+
+ private volatile boolean hasSnapshotCaptureInitiated = false;
public RaftActor(String id, Map<String, String> peerAddresses) {
+ this(id, peerAddresses, Optional.<ConfigParams>absent());
+ }
+
+ public RaftActor(String id, Map<String, String> peerAddresses,
+ Optional<ConfigParams> configParams) {
+
context = new RaftActorContextImpl(this.getSelf(),
- this.getContext(),
- id, new ElectionTermImpl(),
- -1, -1, replicatedLog, peerAddresses, LOG);
+ this.getContext(), id, new ElectionTermImpl(),
+ -1, -1, replicatedLog, peerAddresses,
+ (configParams.isPresent() ? configParams.get(): new DefaultConfigParamsImpl()),
+ LOG);
}
@Override public void onReceiveRecover(Object message) {
if (message instanceof SnapshotOffer) {
+ LOG.debug("SnapshotOffer called..");
SnapshotOffer offer = (SnapshotOffer) message;
Snapshot snapshot = (Snapshot) offer.snapshot();
// when we need to install it on a peer
replicatedLog = new ReplicatedLogImpl(snapshot);
+ context.setReplicatedLog(replicatedLog);
+ context.setLastApplied(snapshot.getLastAppliedIndex());
+
+ LOG.debug("Applied snapshot to replicatedLog. " +
+ "snapshotIndex={}, snapshotTerm={}, journal-size={}",
+ replicatedLog.snapshotIndex, replicatedLog.snapshotTerm,
+ replicatedLog.size());
+
// Apply the snapshot to the actors state
- applySnapshot(snapshot.getState());
+ applySnapshot(ByteString.copyFrom(snapshot.getState()));
} else if (message instanceof ReplicatedLogEntry) {
- replicatedLog.append((ReplicatedLogEntry) message);
+ ReplicatedLogEntry logEntry = (ReplicatedLogEntry) message;
+
+ // Apply State immediately
+ replicatedLog.append(logEntry);
+ applyState(null, "recovery", logEntry.getData());
+ context.setLastApplied(logEntry.getIndex());
+ context.setCommitIndex(logEntry.getIndex());
} else if (message instanceof DeleteEntries) {
replicatedLog.removeFrom(((DeleteEntries) message).getFromIndex());
} else if (message instanceof UpdateElectionTerm) {
context.getTermInformation().update(((UpdateElectionTerm) message).getCurrentTerm(), ((UpdateElectionTerm) message).getVotedFor());
} else if (message instanceof RecoveryCompleted) {
LOG.debug(
- "Last index in log : " + replicatedLog.lastIndex());
+ "RecoveryCompleted - Switching actor to Follower - " +
+ "Persistence Id = " + persistenceId() +
+ " Last index in log:{}, snapshotIndex={}, snapshotTerm={}, " +
+ "journal-size={}",
+ replicatedLog.lastIndex(), replicatedLog.snapshotIndex,
+ replicatedLog.snapshotTerm, replicatedLog.size());
currentBehavior = switchBehavior(RaftState.Follower);
+ onStateChanged();
}
}
applyState.getReplicatedLogEntry().getData());
} else if(message instanceof ApplySnapshot ) {
- applySnapshot(((ApplySnapshot) message).getSnapshot());
+ Snapshot snapshot = ((ApplySnapshot) message).getSnapshot();
+
+ LOG.debug("ApplySnapshot called on Follower Actor " +
+ "snapshotIndex:{}, snapshotTerm:{}", snapshot.getLastAppliedIndex(),
+ snapshot.getLastAppliedTerm());
+ applySnapshot(ByteString.copyFrom(snapshot.getState()));
+
+ //clears the followers log, sets the snapshot index to ensure adjusted-index works
+ replicatedLog = new ReplicatedLogImpl(snapshot);
+ context.setReplicatedLog(replicatedLog);
+ context.setLastApplied(snapshot.getLastAppliedIndex());
} else if (message instanceof FindLeader) {
getSender().tell(
- new FindLeaderReply(
- context.getPeerAddress(currentBehavior.getLeaderId())),
+ new FindLeaderReply(getLeaderAddress()),
getSelf()
);
} else if (message instanceof SaveSnapshotSuccess) {
SaveSnapshotSuccess success = (SaveSnapshotSuccess) message;
+ LOG.info("SaveSnapshotSuccess received for snapshot");
+
+ context.getReplicatedLog().snapshotCommit();
// TODO: Not sure if we want to be this aggressive with trimming stuff
trimPersistentData(success.metadata().sequenceNr());
} else if (message instanceof SaveSnapshotFailure) {
+ SaveSnapshotFailure saveSnapshotFailure = (SaveSnapshotFailure) message;
- // TODO: Handle failure in saving the snapshot
+ LOG.info("saveSnapshotFailure.metadata():{}", saveSnapshotFailure.metadata().toString());
+ LOG.error(saveSnapshotFailure.cause(), "SaveSnapshotFailure received for snapshot Cause:");
- } else if (message instanceof FindLeader){
+ context.getReplicatedLog().snapshotRollback();
- getSender().tell(new FindLeaderReply(
- context.getPeerAddress(currentBehavior.getLeaderId())),
- getSelf());
+ LOG.info("Replicated Log rollbacked. Snapshot will be attempted in the next cycle." +
+ "snapshotIndex:{}, snapshotTerm:{}, log-size:{}",
+ context.getReplicatedLog().getSnapshotIndex(),
+ context.getReplicatedLog().getSnapshotTerm(),
+ context.getReplicatedLog().size());
} else if (message instanceof AddRaftPeer){
RemoveRaftPeer rrp = (RemoveRaftPeer)message;
context.removePeer(rrp.getName());
+ } else if (message instanceof CaptureSnapshot) {
+ LOG.debug("CaptureSnapshot received by actor");
+ CaptureSnapshot cs = (CaptureSnapshot)message;
+ captureSnapshot = cs;
+ createSnapshot();
+
+ } else if (message instanceof CaptureSnapshotReply){
+ LOG.debug("CaptureSnapshotReply received by actor");
+ CaptureSnapshotReply csr = (CaptureSnapshotReply) message;
+
+ ByteString stateInBytes = csr.getSnapshot();
+ LOG.debug("CaptureSnapshotReply stateInBytes size:{}", stateInBytes.size());
+ handleCaptureSnapshotReply(stateInBytes);
+
} else {
+ if (!(message instanceof AppendEntriesMessages.AppendEntries)
+ && !(message instanceof AppendEntriesReply) && !(message instanceof SendHeartBeat)) {
+ LOG.debug("onReceiveCommand: message:" + message.getClass());
+ }
RaftState state =
currentBehavior.handleMessage(getSender(), message);
+ RaftActorBehavior oldBehavior = currentBehavior;
currentBehavior = switchBehavior(state);
+ if(oldBehavior != currentBehavior){
+ onStateChanged();
+ }
+
+ onLeaderChanged(oldBehavior.getLeaderId(), currentBehavior.getLeaderId());
}
}
+ public java.util.Set<String> getPeers() {
+ return context.getPeerAddresses().keySet();
+ }
+
+ protected String getReplicatedLogState() {
+ return "snapshotIndex=" + context.getReplicatedLog().getSnapshotIndex()
+ + ", snapshotTerm=" + context.getReplicatedLog().getSnapshotTerm()
+ + ", im-mem journal size=" + context.getReplicatedLog().size();
+ }
/**
* @return A reference to the leader if known, null otherwise
*/
protected ActorSelection getLeader(){
- String leaderId = currentBehavior.getLeaderId();
- if (leaderId == null) {
+ String leaderAddress = getLeaderAddress();
+
+ if(leaderAddress == null){
return null;
}
- String peerAddress = context.getPeerAddress(leaderId);
- LOG.debug("getLeader leaderId = " + leaderId + " peerAddress = "
- + peerAddress);
- return context.actorSelection(peerAddress);
+
+ return context.actorSelection(leaderAddress);
+ }
+
+ /**
+ *
+ * @return the current leader's id
+ */
+ protected String getLeaderId(){
+ return currentBehavior.getLeaderId();
}
protected RaftState getRaftState() {
return currentBehavior.state();
}
+ protected ReplicatedLogEntry getLastLogEntry() {
+ return replicatedLog.last();
+ }
+
+ protected Long getCurrentTerm(){
+ return context.getTermInformation().getCurrentTerm();
+ }
+
+ protected Long getCommitIndex(){
+ return context.getCommitIndex();
+ }
+
+ protected Long getLastApplied(){
+ return context.getLastApplied();
+ }
+
/**
* setPeerAddress sets the address of a known peer at a later time.
* <p>
*
* @return The current state of the actor
*/
- protected abstract Object createSnapshot();
+ protected abstract void createSnapshot();
/**
* This method will be called by the RaftActor during recovery to
*
* @param snapshot A snapshot of the state of the actor
*/
- protected abstract void applySnapshot(Object snapshot);
+ protected abstract void applySnapshot(ByteString snapshot);
+
+ /**
+ * This method will be called by the RaftActor when the state of the
+ * RaftActor changes. The derived actor can then use methods like
+ * isLeader or getLeader to do something useful
+ */
+ protected abstract void onStateChanged();
+
+ protected void onLeaderChanged(String oldLeader, String newLeader){};
private RaftActorBehavior switchBehavior(RaftState state) {
if (currentBehavior != null) {
} else {
behavior = new Leader(context);
}
+
+
+
return behavior;
}
private void trimPersistentData(long sequenceNumber) {
- // Trim snapshots
+ // Trim akka snapshots
// FIXME : Not sure how exactly the SnapshotSelectionCriteria is applied
// For now guessing that it is ANDed.
deleteSnapshots(new SnapshotSelectionCriteria(
- sequenceNumber - 100000, 43200000));
+ sequenceNumber - context.getConfigParams().getSnapshotBatchCount(), 43200000));
- // Trim journal
+ // Trim akka journal
deleteMessages(sequenceNumber);
}
-
- private class ReplicatedLogImpl implements ReplicatedLog {
- private final List<ReplicatedLogEntry> journal;
- private final Object snapshot;
- private long snapshotIndex = -1;
- private long snapshotTerm = -1;
-
- public ReplicatedLogImpl(Snapshot snapshot) {
- this.snapshot = snapshot.getState();
- this.snapshotIndex = snapshot.getLastAppliedIndex();
- this.snapshotTerm = snapshot.getLastAppliedTerm();
-
- this.journal = new ArrayList<>(snapshot.getUnAppliedEntries());
+ private String getLeaderAddress(){
+ if(isLeader()){
+ return getSelf().path().toString();
}
-
- public ReplicatedLogImpl() {
- this.snapshot = null;
- this.journal = new ArrayList<>();
+ String leaderId = currentBehavior.getLeaderId();
+ if (leaderId == null) {
+ return null;
}
+ String peerAddress = context.getPeerAddress(leaderId);
+ LOG.debug("getLeaderAddress leaderId = " + leaderId + " peerAddress = "
+ + peerAddress);
- @Override public ReplicatedLogEntry get(long index) {
- int adjustedIndex = adjustedIndex(index);
+ return peerAddress;
+ }
- if (adjustedIndex < 0 || adjustedIndex >= journal.size()) {
- return null;
- }
+ private void handleCaptureSnapshotReply(ByteString stateInBytes) {
+ // create a snapshot object from the state provided and save it
+ // when snapshot is saved async, SaveSnapshotSuccess is raised.
- return journal.get(adjustedIndex);
- }
+ Snapshot sn = Snapshot.create(stateInBytes.toByteArray(),
+ context.getReplicatedLog().getFrom(captureSnapshot.getLastAppliedIndex() + 1),
+ captureSnapshot.getLastIndex(), captureSnapshot.getLastTerm(),
+ captureSnapshot.getLastAppliedIndex(), captureSnapshot.getLastAppliedTerm());
- @Override public ReplicatedLogEntry last() {
- if (journal.size() == 0) {
- return null;
- }
- return get(journal.size() - 1);
- }
+ saveSnapshot(sn);
- @Override public long lastIndex() {
- if (journal.size() == 0) {
- return -1;
- }
+ LOG.info("Persisting of snapshot done:{}", sn.getLogMessage());
- return last().getIndex();
- }
+ //be greedy and remove entries from in-mem journal which are in the snapshot
+ // and update snapshotIndex and snapshotTerm without waiting for the success,
- @Override public long lastTerm() {
- if (journal.size() == 0) {
- return -1;
- }
+ context.getReplicatedLog().snapshotPreCommit(stateInBytes,
+ captureSnapshot.getLastAppliedIndex(),
+ captureSnapshot.getLastAppliedTerm());
- return last().getTerm();
- }
+ LOG.info("Removed in-memory snapshotted entries, adjusted snaphsotIndex:{} " +
+ "and term:{}", captureSnapshot.getLastAppliedIndex(),
+ captureSnapshot.getLastAppliedTerm());
+ captureSnapshot = null;
+ hasSnapshotCaptureInitiated = false;
+ }
- @Override public void removeFrom(long index) {
- int adjustedIndex = adjustedIndex(index);
- if (adjustedIndex < 0 || adjustedIndex >= journal.size()) {
- return;
- }
+ private class ReplicatedLogImpl extends AbstractReplicatedLogImpl {
- journal.subList(adjustedIndex , journal.size()).clear();
+ public ReplicatedLogImpl(Snapshot snapshot) {
+ super(ByteString.copyFrom(snapshot.getState()),
+ snapshot.getLastAppliedIndex(), snapshot.getLastAppliedTerm(),
+ snapshot.getUnAppliedEntries());
}
+ public ReplicatedLogImpl() {
+ super();
+ }
- @Override public void removeFromAndPersist(long index) {
- int adjustedIndex = adjustedIndex(index);
+ @Override public void removeFromAndPersist(long logEntryIndex) {
+ int adjustedIndex = adjustedIndex(logEntryIndex);
- if (adjustedIndex < 0 || adjustedIndex >= journal.size()) {
+ if (adjustedIndex < 0) {
return;
}
//FIXME : Doing nothing for now
}
});
-
-
- }
-
- @Override public void append(
- final ReplicatedLogEntry replicatedLogEntry) {
- journal.add(replicatedLogEntry);
- }
-
- @Override public List<ReplicatedLogEntry> getFrom(long index) {
- int adjustedIndex = adjustedIndex(index);
-
- List<ReplicatedLogEntry> entries = new ArrayList<>(100);
- if (adjustedIndex < 0 || adjustedIndex >= journal.size()) {
- return entries;
- }
-
-
- for (int i = adjustedIndex;
- i < journal.size(); i++) {
- entries.add(journal.get(i));
- }
- return entries;
}
@Override public void appendAndPersist(
persist(replicatedLogEntry,
new Procedure<ReplicatedLogEntry>() {
public void apply(ReplicatedLogEntry evt) throws Exception {
- // FIXME : Tentatively create a snapshot every hundred thousand entries. To be tuned.
- if (size() > 100000) {
- ReplicatedLogEntry lastAppliedEntry =
- get(context.getLastApplied());
+ // when a snaphsot is being taken, captureSnapshot != null
+ if (hasSnapshotCaptureInitiated == false &&
+ journal.size() % context.getConfigParams().getSnapshotBatchCount() == 0) {
+
+ LOG.info("Initiating Snapshot Capture..");
long lastAppliedIndex = -1;
long lastAppliedTerm = -1;
+
+ ReplicatedLogEntry lastAppliedEntry = get(context.getLastApplied());
if (lastAppliedEntry != null) {
lastAppliedIndex = lastAppliedEntry.getIndex();
lastAppliedTerm = lastAppliedEntry.getTerm();
}
- saveSnapshot(Snapshot.create(createSnapshot(),
- getFrom(context.getLastApplied() + 1),
- lastIndex(), lastTerm(), lastAppliedIndex,
- lastAppliedTerm));
+ LOG.debug("Snapshot Capture logSize: {}", journal.size());
+ LOG.debug("Snapshot Capture lastApplied:{} ", context.getLastApplied());
+ LOG.debug("Snapshot Capture lastAppliedIndex:{}", lastAppliedIndex);
+ LOG.debug("Snapshot Capture lastAppliedTerm:{}", lastAppliedTerm);
+
+ // send a CaptureSnapshot to self to make the expensive operation async.
+ getSelf().tell(new CaptureSnapshot(
+ lastIndex(), lastTerm(), lastAppliedIndex, lastAppliedTerm),
+ null);
+ hasSnapshotCaptureInitiated = true;
}
// Send message for replication
if (clientActor != null) {
);
}
- @Override public long size() {
- return journal.size() + snapshotIndex + 1;
- }
-
- @Override public boolean isPresent(long index) {
- int adjustedIndex = adjustedIndex(index);
-
- if (adjustedIndex < 0 || adjustedIndex >= journal.size()) {
- return false;
- }
- return true;
- }
-
- @Override public boolean isInSnapshot(long index) {
- return index <= snapshotIndex;
- }
-
- @Override public Object getSnapshot() {
- return snapshot;
- }
-
- @Override public long getSnapshotIndex() {
- return snapshotIndex;
- }
-
- @Override public long getSnapshotTerm() {
- return snapshotTerm;
- }
-
- private int adjustedIndex(long index) {
- if(snapshotIndex < 0){
- return (int) index;
- }
- return (int) (index - snapshotIndex);
- }
}
-
-
-
private static class DeleteEntries implements Serializable {
private final int fromIndex;
}
- private static class Snapshot implements Serializable {
- private final Object state;
- private final List<ReplicatedLogEntry> unAppliedEntries;
- private final long lastIndex;
- private final long lastTerm;
- private final long lastAppliedIndex;
- private final long lastAppliedTerm;
-
- private Snapshot(Object state,
- List<ReplicatedLogEntry> unAppliedEntries, long lastIndex,
- long lastTerm, long lastAppliedIndex, long lastAppliedTerm) {
- this.state = state;
- this.unAppliedEntries = unAppliedEntries;
- this.lastIndex = lastIndex;
- this.lastTerm = lastTerm;
- this.lastAppliedIndex = lastAppliedIndex;
- this.lastAppliedTerm = lastAppliedTerm;
- }
-
-
- public static Snapshot create(Object state,
- List<ReplicatedLogEntry> entries, long lastIndex, long lastTerm,
- long lastAppliedIndex, long lastAppliedTerm) {
- return new Snapshot(state, entries, lastIndex, lastTerm,
- lastAppliedIndex, lastAppliedTerm);
- }
-
- public Object getState() {
- return state;
- }
-
- public List<ReplicatedLogEntry> getUnAppliedEntries() {
- return unAppliedEntries;
- }
-
- public long getLastTerm() {
- return lastTerm;
- }
-
- public long getLastAppliedIndex() {
- return lastAppliedIndex;
- }
-
- public long getLastAppliedTerm() {
- return lastAppliedTerm;
- }
- }
-
private class ElectionTermImpl implements ElectionTerm {
/**
* Identifier of the actor whose election term information this is
}
@Override public void update(long currentTerm, String votedFor) {
- LOG.info("Set currentTerm={}, votedFor={}", currentTerm, votedFor);
+ LOG.debug("Set currentTerm={}, votedFor={}", currentTerm, votedFor);
this.currentTerm = currentTerm;
this.votedFor = votedFor;