* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
-
package org.opendaylight.controller.cluster.raft.behaviors;
+import static java.util.Objects.requireNonNull;
+
import akka.actor.ActorRef;
import akka.actor.ActorSelection;
import akka.actor.Cancellable;
import com.google.common.annotations.VisibleForTesting;
-import com.google.common.base.Optional;
-import com.google.common.base.Preconditions;
-import com.google.common.base.Throwables;
import com.google.common.io.ByteSource;
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
-import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
+import java.util.Optional;
+import java.util.OptionalInt;
import java.util.Queue;
import java.util.concurrent.TimeUnit;
-import javax.annotation.Nullable;
+import org.eclipse.jdt.annotation.Nullable;
import org.opendaylight.controller.cluster.io.SharedFileBackedOutputStream;
import org.opendaylight.controller.cluster.messaging.MessageSlicer;
import org.opendaylight.controller.cluster.messaging.SliceOptions;
import org.opendaylight.controller.cluster.raft.ClientRequestTracker;
-import org.opendaylight.controller.cluster.raft.ClientRequestTrackerImpl;
import org.opendaylight.controller.cluster.raft.FollowerLogInformation;
-import org.opendaylight.controller.cluster.raft.FollowerLogInformationImpl;
import org.opendaylight.controller.cluster.raft.PeerInfo;
import org.opendaylight.controller.cluster.raft.RaftActorContext;
import org.opendaylight.controller.cluster.raft.RaftState;
+import org.opendaylight.controller.cluster.raft.RaftVersions;
import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
import org.opendaylight.controller.cluster.raft.VotingState;
+import org.opendaylight.controller.cluster.raft.base.messages.ApplyState;
import org.opendaylight.controller.cluster.raft.base.messages.CheckConsensusReached;
import org.opendaylight.controller.cluster.raft.base.messages.Replicate;
import org.opendaylight.controller.cluster.raft.base.messages.SendHeartBeat;
import org.opendaylight.controller.cluster.raft.base.messages.SendInstallSnapshot;
import org.opendaylight.controller.cluster.raft.messages.AppendEntries;
import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
+import org.opendaylight.controller.cluster.raft.messages.IdentifiablePayload;
import org.opendaylight.controller.cluster.raft.messages.InstallSnapshot;
import org.opendaylight.controller.cluster.raft.messages.InstallSnapshotReply;
import org.opendaylight.controller.cluster.raft.messages.RaftRPC;
import scala.concurrent.duration.FiniteDuration;
/**
- * The behavior of a RaftActor when it is in the Leader state
+ * The behavior of a RaftActor when it is in the Leader state.
*
* <p>
* Leaders:
private final MessageSlicer appendEntriesMessageSlicer;
private Cancellable heartbeatSchedule = null;
- private Optional<SnapshotHolder> snapshotHolder = Optional.absent();
+ private Optional<SnapshotHolder> snapshotHolder = Optional.empty();
private int minReplicationCount;
- protected AbstractLeader(RaftActorContext context, RaftState state,
- @Nullable AbstractLeader initializeFromLeader) {
+ protected AbstractLeader(final RaftActorContext context, final RaftState state,
+ final @Nullable AbstractLeader initializeFromLeader) {
super(context, state);
appendEntriesMessageSlicer = MessageSlicer.builder().logContext(logName())
trackers.addAll(initializeFromLeader.trackers);
} else {
for (PeerInfo peerInfo: context.getPeers()) {
- FollowerLogInformation followerLogInformation = new FollowerLogInformationImpl(peerInfo, -1, context);
+ FollowerLogInformation followerLogInformation = new FollowerLogInformation(peerInfo, context);
followerToLog.put(peerInfo.getId(), followerLogInformation);
}
}
scheduleHeartBeat(context.getConfigParams().getHeartBeatInterval());
}
- protected AbstractLeader(RaftActorContext context, RaftState state) {
+ protected AbstractLeader(final RaftActorContext context, final RaftState state) {
this(context, state, null);
}
return followerToLog.keySet();
}
- public void addFollower(String followerId) {
- FollowerLogInformation followerLogInformation = new FollowerLogInformationImpl(
- context.getPeerInfo(followerId), -1, context);
+ public void addFollower(final String followerId) {
+ FollowerLogInformation followerLogInformation = new FollowerLogInformation(context.getPeerInfo(followerId),
+ context);
followerToLog.put(followerId, followerLogInformation);
if (heartbeatSchedule == null) {
}
}
- public void removeFollower(String followerId) {
+ public void removeFollower(final String followerId) {
followerToLog.remove(followerId);
}
- public void updateMinReplicaCount() {
+ public final void updateMinReplicaCount() {
int numVoting = 0;
for (PeerInfo peer: context.getPeers()) {
if (peer.isVoting()) {
}
@VisibleForTesting
- void setSnapshot(@Nullable SnapshotHolder snapshotHolder) {
- this.snapshotHolder = Optional.fromNullable(snapshotHolder);
+ void setSnapshotHolder(final @Nullable SnapshotHolder snapshotHolder) {
+ this.snapshotHolder = Optional.ofNullable(snapshotHolder);
}
@VisibleForTesting
}
@Override
- protected RaftActorBehavior handleAppendEntries(ActorRef sender,
- AppendEntries appendEntries) {
+ protected RaftActorBehavior handleAppendEntries(final ActorRef sender,
+ final AppendEntries appendEntries) {
log.debug("{}: handleAppendEntries: {}", logName(), appendEntries);
}
@Override
- protected RaftActorBehavior handleAppendEntriesReply(ActorRef sender, AppendEntriesReply appendEntriesReply) {
+ protected RaftActorBehavior handleAppendEntriesReply(final ActorRef sender,
+ final AppendEntriesReply appendEntriesReply) {
log.trace("{}: handleAppendEntriesReply: {}", logName(), appendEntriesReply);
// Update the FollowerLogInformation
return this;
}
- if (followerLogInformation.timeSinceLastActivity()
- > context.getConfigParams().getElectionTimeOutInterval().toMillis()) {
+ final var followerRaftVersion = appendEntriesReply.getRaftVersion();
+ if (followerRaftVersion < RaftVersions.FLUORINE_VERSION) {
+ log.warn("{}: handleAppendEntriesReply - ignoring reply from follower {} raft version {}", logName(),
+ followerId, followerRaftVersion);
+ return this;
+ }
+
+ final long lastActivityNanos = followerLogInformation.nanosSinceLastActivity();
+ if (lastActivityNanos > context.getConfigParams().getElectionTimeOutInterval().toNanos()) {
log.warn("{} : handleAppendEntriesReply delayed beyond election timeout, "
+ "appendEntriesReply : {}, timeSinceLastActivity : {}, lastApplied : {}, commitIndex : {}",
- logName(), appendEntriesReply, followerLogInformation.timeSinceLastActivity(),
+ logName(), appendEntriesReply, TimeUnit.NANOSECONDS.toMillis(lastActivityNanos),
context.getLastApplied(), context.getCommitIndex());
}
followerLogInformation.markFollowerActive();
followerLogInformation.setPayloadVersion(appendEntriesReply.getPayloadVersion());
- followerLogInformation.setRaftVersion(appendEntriesReply.getRaftVersion());
+ followerLogInformation.setRaftVersion(followerRaftVersion);
+ followerLogInformation.setNeedsLeaderAddress(appendEntriesReply.isNeedsLeaderAddress());
long followerLastLogIndex = appendEntriesReply.getLogLastIndex();
- long followersLastLogTermInLeadersLog = getLogEntryTerm(followerLastLogIndex);
boolean updated = false;
if (appendEntriesReply.getLogLastIndex() > context.getReplicatedLog().lastIndex()) {
// The follower's log is actually ahead of the leader's log. Normally this doesn't happen
// However in this case the log terms won't match and the logs will conflict - this is handled
// elsewhere.
log.info("{}: handleAppendEntriesReply: follower {} lastIndex {} is ahead of our lastIndex {} "
- + "(snapshotIndex {}) - forcing install snaphot", logName(), followerLogInformation.getId(),
- appendEntriesReply.getLogLastIndex(), context.getReplicatedLog().lastIndex(),
- context.getReplicatedLog().getSnapshotIndex());
+ + "(snapshotIndex {}, snapshotTerm {}) - forcing install snaphot", logName(),
+ followerLogInformation.getId(), appendEntriesReply.getLogLastIndex(),
+ context.getReplicatedLog().lastIndex(), context.getReplicatedLog().getSnapshotIndex(),
+ context.getReplicatedLog().getSnapshotTerm());
followerLogInformation.setMatchIndex(-1);
followerLogInformation.setNextIndex(-1);
updated = true;
} else if (appendEntriesReply.isSuccess()) {
+ long followersLastLogTermInLeadersLog = getLogEntryTerm(followerLastLogIndex);
if (followerLastLogIndex >= 0 && followersLastLogTermInLeadersLog >= 0
&& followersLastLogTermInLeadersLog != appendEntriesReply.getLogLastTerm()) {
// The follower's last entry is present in the leader's journal but the terms don't match so the
updated = updateFollowerLogInformation(followerLogInformation, appendEntriesReply);
}
} else {
- log.info("{}: handleAppendEntriesReply - received unsuccessful reply: {}, leader snapshotIndex: {}",
- logName(), appendEntriesReply, context.getReplicatedLog().getSnapshotIndex());
+ log.info("{}: handleAppendEntriesReply - received unsuccessful reply: {}, leader snapshotIndex: {}, "
+ + "snapshotTerm: {}, replicatedToAllIndex: {}", logName(), appendEntriesReply,
+ context.getReplicatedLog().getSnapshotIndex(), context.getReplicatedLog().getSnapshotTerm(),
+ getReplicatedToAllIndex());
+ long followersLastLogTermInLeadersLogOrSnapshot = getLogEntryOrSnapshotTerm(followerLastLogIndex);
if (appendEntriesReply.isForceInstallSnapshot()) {
// Reset the followers match and next index. This is to signal that this follower has nothing
// in common with this Leader and so would require a snapshot to be installed
// Force initiate a snapshot capture
initiateCaptureSnapshot(followerId);
- } else if (followerLastLogIndex < 0 || followersLastLogTermInLeadersLog >= 0
- && followersLastLogTermInLeadersLog == appendEntriesReply.getLogLastTerm()) {
- // The follower's log is empty or the last entry is present in the leader's journal
- // and the terms match so the follower is just behind the leader's journal from
- // the last snapshot, if any. We'll catch up the follower quickly by starting at the
- // follower's last log index.
+ } else if (followerLastLogIndex < 0 || followersLastLogTermInLeadersLogOrSnapshot >= 0
+ && followersLastLogTermInLeadersLogOrSnapshot == appendEntriesReply.getLogLastTerm()) {
+ // The follower's log is empty or the follower's last entry is present in the leader's journal or
+ // snapshot and the terms match so the follower is just behind the leader's journal from the last
+ // snapshot, if any. We'll catch up the follower quickly by starting at the follower's last log index.
updated = updateFollowerLogInformation(followerLogInformation, appendEntriesReply);
log.info("{}: follower {} appears to be behind the leader from the last snapshot - "
+ "updated: matchIndex: {}, nextIndex: {}", logName(), followerId,
- appendEntriesReply.getLogLastTerm(), followerLogInformation.getMatchIndex(),
- followerLogInformation.getNextIndex());
+ followerLogInformation.getMatchIndex(), followerLogInformation.getNextIndex());
} else {
- // The follower's log conflicts with leader's log so decrement follower's next index by 1
+ // The follower's log conflicts with leader's log so decrement follower's next index
// in an attempt to find where the logs match.
-
- if (followerLogInformation.decrNextIndex()) {
+ if (followerLogInformation.decrNextIndex(appendEntriesReply.getLogLastIndex())) {
updated = true;
log.info("{}: follower {} last log term {} conflicts with the leader's {} - dec next index to {}",
logName(), followerId, appendEntriesReply.getLogLastTerm(),
- followersLastLogTermInLeadersLog, followerLogInformation.getNextIndex());
+ followersLastLogTermInLeadersLogOrSnapshot, followerLogInformation.getNextIndex());
}
}
}
}
}
- private boolean updateFollowerLogInformation(FollowerLogInformation followerLogInformation,
- AppendEntriesReply appendEntriesReply) {
+ private boolean updateFollowerLogInformation(final FollowerLogInformation followerLogInformation,
+ final AppendEntriesReply appendEntriesReply) {
boolean updated = followerLogInformation.setMatchIndex(appendEntriesReply.getLogLastIndex());
updated = followerLogInformation.setNextIndex(appendEntriesReply.getLogLastIndex() + 1) || updated;
super.performSnapshotWithoutCapture(minReplicatedToAllIndex);
}
- @Override
- protected ClientRequestTracker removeClientRequestTracker(long logIndex) {
- final Iterator<ClientRequestTracker> it = trackers.iterator();
+ /**
+ * Removes and returns the ClientRequestTracker for the specified log index.
+ * @param logIndex the log index
+ * @return the ClientRequestTracker or null if none available
+ */
+ private ClientRequestTracker removeClientRequestTracker(final long logIndex) {
+ final var it = trackers.iterator();
while (it.hasNext()) {
- final ClientRequestTracker t = it.next();
- if (t.getIndex() == logIndex) {
+ final var tracker = it.next();
+ if (tracker.logIndex() == logIndex) {
it.remove();
- return t;
+ return tracker;
}
}
-
return null;
}
@Override
- protected RaftActorBehavior handleRequestVoteReply(ActorRef sender,
- RequestVoteReply requestVoteReply) {
+ final ApplyState getApplyStateFor(final ReplicatedLogEntry entry) {
+ // first check whether a ClientRequestTracker exists for this entry.
+ // If it does that means the leader wasn't dropped before the transaction applied.
+ // That means that this transaction can be safely applied as a local transaction since we
+ // have the ClientRequestTracker.
+ final var tracker = removeClientRequestTracker(entry.getIndex());
+ if (tracker != null) {
+ return new ApplyState(tracker.clientActor(), tracker.identifier(), entry);
+ }
+
+ // Tracker is missing, this means that we switched behaviours between replicate and applystate
+ // and became the leader again,. We still want to apply this as a local modification because
+ // we have resumed leadership with that log entry having been committed.
+ if (entry.getData() instanceof IdentifiablePayload<?> identifiable) {
+ return new ApplyState(null, identifiable.getIdentifier(), entry);
+ }
+
+ return new ApplyState(null, null, entry);
+ }
+
+ @Override
+ protected RaftActorBehavior handleRequestVoteReply(final ActorRef sender, final RequestVoteReply requestVoteReply) {
return this;
}
- protected void beforeSendHeartbeat(){}
+ protected void beforeSendHeartbeat() {
+ // No-op
+ }
@Override
- public RaftActorBehavior handleMessage(ActorRef sender, Object message) {
- Preconditions.checkNotNull(sender, "sender should not be null");
+ public RaftActorBehavior handleMessage(final ActorRef sender, final Object message) {
+ requireNonNull(sender, "sender should not be null");
if (appendEntriesMessageSlicer.handleMessage(message)) {
return this;
}
- if (message instanceof RaftRPC) {
- RaftRPC rpc = (RaftRPC) message;
- // If RPC request or response contains term T > currentTerm:
- // set currentTerm = T, convert to follower (§5.1)
- // This applies to all RPC messages and responses
- if (rpc.getTerm() > context.getTermInformation().getCurrentTerm()) {
- log.info("{}: Term {} in \"{}\" message is greater than leader's term {} - switching to Follower",
- logName(), rpc.getTerm(), rpc, context.getTermInformation().getCurrentTerm());
-
- context.getTermInformation().updateAndPersist(rpc.getTerm(), null);
-
- // This is a special case. Normally when stepping down as leader we don't process and reply to the
- // RaftRPC as per raft. But if we're in the process of transferring leadership and we get a
- // RequestVote, process the RequestVote before switching to Follower. This enables the requesting
- // candidate node to be elected the leader faster and avoids us possibly timing out in the Follower
- // state and starting a new election and grabbing leadership back before the other candidate node can
- // start a new election due to lack of responses. This case would only occur if there isn't a majority
- // of other nodes available that can elect the requesting candidate. Since we're transferring
- // leadership, we should make every effort to get the requesting node elected.
- if (message instanceof RequestVote && context.getRaftActorLeadershipTransferCohort() != null) {
- log.debug("{}: Leadership transfer in progress - processing RequestVote", logName());
- super.handleMessage(sender, message);
- }
-
- return internalSwitchBehavior(RaftState.Follower);
+ // If RPC request or response contains term T > currentTerm:
+ // set currentTerm = T, convert to follower (§5.1)
+ // This applies to all RPC messages and responses
+ if (message instanceof RaftRPC rpc && rpc.getTerm() > context.getTermInformation().getCurrentTerm()
+ && shouldUpdateTerm(rpc)) {
+
+ log.info("{}: Term {} in \"{}\" message is greater than leader's term {} - switching to Follower",
+ logName(), rpc.getTerm(), rpc, context.getTermInformation().getCurrentTerm());
+
+ context.getTermInformation().updateAndPersist(rpc.getTerm(), null);
+
+ // This is a special case. Normally when stepping down as leader we don't process and reply to the
+ // RaftRPC as per raft. But if we're in the process of transferring leadership and we get a
+ // RequestVote, process the RequestVote before switching to Follower. This enables the requesting
+ // candidate node to be elected the leader faster and avoids us possibly timing out in the Follower
+ // state and starting a new election and grabbing leadership back before the other candidate node can
+ // start a new election due to lack of responses. This case would only occur if there isn't a majority
+ // of other nodes available that can elect the requesting candidate. Since we're transferring
+ // leadership, we should make every effort to get the requesting node elected.
+ if (rpc instanceof RequestVote requestVote && context.getRaftActorLeadershipTransferCohort() != null) {
+ log.debug("{}: Leadership transfer in progress - processing RequestVote", logName());
+ requestVote(sender, requestVote);
}
+
+ return internalSwitchBehavior(RaftState.Follower);
}
if (message instanceof SendHeartBeat) {
beforeSendHeartbeat();
sendHeartBeat();
scheduleHeartBeat(context.getConfigParams().getHeartBeatInterval());
- } else if (message instanceof SendInstallSnapshot) {
- SendInstallSnapshot sendInstallSnapshot = (SendInstallSnapshot) message;
- setSnapshot(new SnapshotHolder(sendInstallSnapshot.getSnapshot(), sendInstallSnapshot.getSnapshotBytes()));
+ } else if (message instanceof SendInstallSnapshot sendInstallSnapshot) {
+ setSnapshotHolder(new SnapshotHolder(sendInstallSnapshot.getSnapshot(),
+ sendInstallSnapshot.getSnapshotBytes()));
sendInstallSnapshot();
- } else if (message instanceof Replicate) {
- replicate((Replicate) message);
- } else if (message instanceof InstallSnapshotReply) {
- handleInstallSnapshotReply((InstallSnapshotReply) message);
+ } else if (message instanceof Replicate replicate) {
+ replicate(replicate);
+ } else if (message instanceof InstallSnapshotReply installSnapshotReply) {
+ handleInstallSnapshotReply(installSnapshotReply);
} else if (message instanceof CheckConsensusReached) {
possiblyUpdateCommitIndex();
} else {
return this;
}
- private void handleInstallSnapshotReply(InstallSnapshotReply reply) {
+ @SuppressFBWarnings(value = "NP_NULL_PARAM_DEREF_ALL_TARGETS_DANGEROUS",
+ justification = "JDT nullness with SpotBugs at setSnapshotHolder(null)")
+ private void handleInstallSnapshotReply(final InstallSnapshotReply reply) {
log.debug("{}: handleInstallSnapshotReply: {}", logName(), reply);
String followerId = reply.getFollowerId();
return;
}
+ installSnapshotState.resetChunkTimer();
followerLogInformation.markFollowerActive();
if (installSnapshotState.getChunkIndex() == reply.getChunkIndex()) {
if (installSnapshotState.isLastChunk(reply.getChunkIndex())) {
//this was the last chunk reply
- long followerMatchIndex = snapshotHolder.get().getLastIncludedIndex();
+ long followerMatchIndex = snapshotHolder.orElseThrow().getLastIncludedIndex();
followerLogInformation.setMatchIndex(followerMatchIndex);
followerLogInformation.setNextIndex(followerMatchIndex + 1);
followerLogInformation.clearLeaderInstallSnapshotState();
if (!anyFollowersInstallingSnapshot()) {
// once there are no pending followers receiving snapshots
// we can remove snapshot from the memory
- setSnapshot(null);
+ setSnapshotHolder(null);
}
wasLastChunk = true;
return false;
}
- private void replicate(Replicate replicate) {
- long logIndex = replicate.getReplicatedLogEntry().getIndex();
+ private void replicate(final Replicate replicate) {
+ final long logIndex = replicate.logIndex();
- log.debug("{}: Replicate message: identifier: {}, logIndex: {}, payload: {}, isSendImmediate: {}", logName(),
- replicate.getIdentifier(), logIndex, replicate.getReplicatedLogEntry().getData().getClass(),
- replicate.isSendImmediate());
+ log.debug("{}: Replicate message: identifier: {}, logIndex: {}, isSendImmediate: {}", logName(),
+ replicate.identifier(), logIndex, replicate.sendImmediate());
// Create a tracker entry we will use this later to notify the
// client actor
- if (replicate.getClientActor() != null) {
- trackers.add(new ClientRequestTrackerImpl(replicate.getClientActor(), replicate.getIdentifier(),
- logIndex));
+ final var clientActor = replicate.clientActor();
+ if (clientActor != null) {
+ trackers.add(new ClientRequestTracker(logIndex, clientActor, replicate.identifier()));
}
boolean applyModificationToState = !context.anyVotingPeers()
applyLogToStateMachine(logIndex);
}
- if (replicate.isSendImmediate() && !followerToLog.isEmpty()) {
+ if (replicate.sendImmediate() && !followerToLog.isEmpty()) {
sendAppendEntries(0, false);
}
}
- protected void sendAppendEntries(long timeSinceLastActivityInterval, boolean isHeartbeat) {
+ protected void sendAppendEntries(final long timeSinceLastActivityIntervalNanos, final boolean isHeartbeat) {
// Send an AppendEntries to all followers
for (Entry<String, FollowerLogInformation> e : followerToLog.entrySet()) {
final String followerId = e.getKey();
final FollowerLogInformation followerLogInformation = e.getValue();
// This checks helps not to send a repeat message to the follower
if (!followerLogInformation.isFollowerActive()
- || followerLogInformation.timeSinceLastActivity() >= timeSinceLastActivityInterval) {
+ || followerLogInformation.nanosSinceLastActivity() >= timeSinceLastActivityIntervalNanos) {
sendUpdatesToFollower(followerId, followerLogInformation, true, isHeartbeat);
}
}
* This method checks if any update needs to be sent to the given follower. This includes append log entries,
* sending next snapshot chunk, and initiating a snapshot.
*/
- private void sendUpdatesToFollower(String followerId, FollowerLogInformation followerLogInformation,
- boolean sendHeartbeat, boolean isHeartbeat) {
+ private void sendUpdatesToFollower(final String followerId, final FollowerLogInformation followerLogInformation,
+ final boolean sendHeartbeat, final boolean isHeartbeat) {
ActorSelection followerActor = context.getPeerActorSelection(followerId);
if (followerActor != null) {
LeaderInstallSnapshotState installSnapshotState = followerLogInformation.getInstallSnapshotState();
if (installSnapshotState != null) {
+
// if install snapshot is in process , then sent next chunk if possible
- if (isFollowerActive && installSnapshotState.canSendNextChunk()) {
- sendSnapshotChunk(followerActor, followerLogInformation);
- } else if (sendHeartbeat) {
+ if (isFollowerActive) {
+ // 30 seconds with default settings, can be modified via heartbeat or election timeout factor
+ FiniteDuration snapshotReplyTimeout = context.getConfigParams().getHeartBeatInterval()
+ .$times(context.getConfigParams().getElectionTimeoutFactor() * 3);
+
+ if (installSnapshotState.isChunkTimedOut(snapshotReplyTimeout)) {
+ sendAppendEntries = !resendSnapshotChunk(followerActor, followerLogInformation);
+ } else if (installSnapshotState.canSendNextChunk()) {
+ sendSnapshotChunk(followerActor, followerLogInformation);
+ }
+ } else if (sendHeartbeat || followerLogInformation.hasStaleCommitIndex(context.getCommitIndex())) {
// we send a heartbeat even if we have not received a reply for the last chunk
sendAppendEntries = true;
}
log.debug("{}: sendAppendEntries: {} is present for follower {}", logName(),
followerNextIndex, followerId);
- if (followerLogInformation.okToReplicate()) {
+ if (followerLogInformation.okToReplicate(context.getCommitIndex())) {
entries = getEntriesToSend(followerLogInformation, followerActor);
sendAppendEntries = true;
}
context.getReplicatedLog().size());
}
- } else if (sendHeartbeat) {
+ } else if (sendHeartbeat || followerLogInformation.hasStaleCommitIndex(context.getCommitIndex())) {
// we send an AppendEntries, even if the follower is inactive
// in-order to update the followers timestamp, in case it becomes active again
sendAppendEntries = true;
}
}
- private List<ReplicatedLogEntry> getEntriesToSend(FollowerLogInformation followerLogInfo,
- ActorSelection followerActor) {
+ private List<ReplicatedLogEntry> getEntriesToSend(final FollowerLogInformation followerLogInfo,
+ final ActorSelection followerActor) {
// Try to get all the entries in the journal but not exceeding the max data size for a single AppendEntries
// message.
int maxEntries = (int) context.getReplicatedLog().size();
// If the first entry's size exceeds the max data size threshold, it will be returned from the call above. If
// that is the case, then we need to slice it into smaller chunks.
- if (!(entries.size() == 1 && entries.get(0).getData().size() > maxDataSize)) {
+ if (entries.size() != 1 || entries.get(0).getData().serializedSize() <= maxDataSize) {
// Don't need to slice.
return entries;
}
return Collections.emptyList();
}
- private void sendAppendEntriesToFollower(ActorSelection followerActor, List<ReplicatedLogEntry> entries,
- FollowerLogInformation followerLogInformation) {
+ private void sendAppendEntriesToFollower(final ActorSelection followerActor, final List<ReplicatedLogEntry> entries,
+ final FollowerLogInformation followerLogInformation) {
// In certain cases outlined below we don't want to send the actual commit index to prevent the follower from
// possibly committing and applying conflicting entries (those with same index, different term) from a prior
// term that weren't replicated to a majority, which would be a violation of raft.
AppendEntries appendEntries = new AppendEntries(currentTerm(), context.getId(),
getLogEntryIndex(followerNextIndex - 1),
getLogEntryTerm(followerNextIndex - 1), entries,
- leaderCommitIndex, super.getReplicatedToAllIndex(), context.getPayloadVersion());
+ leaderCommitIndex, super.getReplicatedToAllIndex(), context.getPayloadVersion(),
+ followerLogInformation.getRaftVersion(), followerLogInformation.needsLeaderAddress(getId()));
if (!entries.isEmpty() || log.isTraceEnabled()) {
log.debug("{}: Sending AppendEntries to follower {}: {}", logName(), followerLogInformation.getId(),
appendEntries);
}
+ followerLogInformation.setSentCommitIndex(leaderCommitIndex);
followerActor.tell(appendEntries, actor());
}
* @param followerId the id of the follower.
* @return true if capture was initiated, false otherwise.
*/
- public boolean initiateCaptureSnapshot(String followerId) {
+ public boolean initiateCaptureSnapshot(final String followerId) {
FollowerLogInformation followerLogInfo = followerToLog.get(followerId);
if (snapshotHolder.isPresent()) {
// If a snapshot is present in the memory, most likely another install is in progress no need to capture
}
boolean captureInitiated = context.getSnapshotManager().captureToInstall(context.getReplicatedLog().last(),
- this.getReplicatedToAllIndex(), followerId);
+ getReplicatedToAllIndex(), followerId);
if (captureInitiated) {
followerLogInfo.setLeaderInstallSnapshotState(new LeaderInstallSnapshotState(
context.getConfigParams().getSnapshotChunkSize(), logName()));
return captureInitiated;
}
- private boolean canInstallSnapshot(long nextIndex) {
+ private boolean canInstallSnapshot(final long nextIndex) {
// If the follower's nextIndex is -1 then we might as well send it a snapshot
// Otherwise send it a snapshot only if the nextIndex is not present in the log but is present
// in the snapshot
* Sends a snapshot chunk to a given follower
* InstallSnapshot should qualify as a heartbeat too.
*/
- private void sendSnapshotChunk(ActorSelection followerActor, FollowerLogInformation followerLogInfo) {
+ private void sendSnapshotChunk(final ActorSelection followerActor, final FollowerLogInformation followerLogInfo) {
if (snapshotHolder.isPresent()) {
LeaderInstallSnapshotState installSnapshotState = followerLogInfo.getInstallSnapshotState();
if (installSnapshotState == null) {
try {
// Ensure the snapshot bytes are set - this is a no-op.
- installSnapshotState.setSnapshotBytes(snapshotHolder.get().getSnapshotBytes());
+ installSnapshotState.setSnapshotBytes(snapshotHolder.orElseThrow().getSnapshotBytes());
if (!installSnapshotState.canSendNextChunk()) {
return;
nextSnapshotChunk.length);
int nextChunkIndex = installSnapshotState.incrementChunkIndex();
- Optional<ServerConfigurationPayload> serverConfig = Optional.absent();
+ Optional<ServerConfigurationPayload> serverConfig = Optional.empty();
if (installSnapshotState.isLastChunk(nextChunkIndex)) {
- serverConfig = Optional.fromNullable(context.getPeerServerInfo(true));
+ serverConfig = Optional.ofNullable(context.getPeerServerInfo(true));
}
- followerActor.tell(
- new InstallSnapshot(currentTerm(), context.getId(),
- snapshotHolder.get().getLastIncludedIndex(),
- snapshotHolder.get().getLastIncludedTerm(),
- nextSnapshotChunk,
- nextChunkIndex,
- installSnapshotState.getTotalChunks(),
- Optional.of(installSnapshotState.getLastChunkHashCode()),
- serverConfig
- ).toSerializable(followerLogInfo.getRaftVersion()),
- actor()
- );
+ sendSnapshotChunk(followerActor, followerLogInfo, nextSnapshotChunk, nextChunkIndex, serverConfig);
log.debug("{}: InstallSnapshot sent to follower {}, Chunk: {}/{}", logName(), followerActor.path(),
installSnapshotState.getChunkIndex(), installSnapshotState.getTotalChunks());
+
} catch (IOException e) {
- throw Throwables.propagate(e);
+ log.warn("{}: Unable to send chunk: {}/{}. Reseting snapshot progress. Snapshot state: {}", logName(),
+ installSnapshotState.getChunkIndex(), installSnapshotState.getTotalChunks(),
+ installSnapshotState, e);
+ installSnapshotState.reset();
}
}
}
+ private void sendSnapshotChunk(final ActorSelection followerActor, final FollowerLogInformation followerLogInfo,
+ final byte[] snapshotChunk, final int chunkIndex,
+ final Optional<ServerConfigurationPayload> serverConfig) {
+ LeaderInstallSnapshotState installSnapshotState = followerLogInfo.getInstallSnapshotState();
+
+ installSnapshotState.startChunkTimer();
+ followerActor.tell(
+ new InstallSnapshot(currentTerm(), context.getId(),
+ snapshotHolder.orElseThrow().getLastIncludedIndex(),
+ snapshotHolder.orElseThrow().getLastIncludedTerm(),
+ snapshotChunk,
+ chunkIndex,
+ installSnapshotState.getTotalChunks(),
+ OptionalInt.of(installSnapshotState.getLastChunkHashCode()),
+ serverConfig,
+ followerLogInfo.getRaftVersion()),
+ actor()
+ );
+ }
+
+ private boolean resendSnapshotChunk(final ActorSelection followerActor,
+ final FollowerLogInformation followerLogInfo) {
+ if (!snapshotHolder.isPresent()) {
+ // Seems like we should never hit this case, but just in case we do, reset the snapshot progress so that it
+ // can restart from the next AppendEntries.
+ log.warn("{}: Attempting to resend snapshot with no snapshot holder present.", logName());
+ followerLogInfo.clearLeaderInstallSnapshotState();
+ return false;
+ }
+
+ LeaderInstallSnapshotState installSnapshotState = followerLogInfo.getInstallSnapshotState();
+ // we are resending, timer needs to be reset
+ installSnapshotState.resetChunkTimer();
+ installSnapshotState.markSendStatus(false);
+
+ sendSnapshotChunk(followerActor, followerLogInfo);
+
+ return true;
+ }
+
private void sendHeartBeat() {
if (!followerToLog.isEmpty()) {
log.trace("{}: Sending heartbeat", logName());
- sendAppendEntries(context.getConfigParams().getHeartBeatInterval().toMillis(), true);
+ sendAppendEntries(context.getConfigParams().getHeartBeatInterval().toNanos(), true);
appendEntriesMessageSlicer.checkExpiredSlicedMessageState();
}
}
}
- private void scheduleHeartBeat(FiniteDuration interval) {
+ private void scheduleHeartBeat(final FiniteDuration interval) {
if (followerToLog.isEmpty()) {
// Optimization - do not bother scheduling a heartbeat as there are
// no followers
}
@VisibleForTesting
- public FollowerLogInformation getFollower(String followerId) {
+ public FollowerLogInformation getFollower(final String followerId) {
return followerToLog.get(followerId);
}
private final long lastIncludedIndex;
private final ByteSource snapshotBytes;
- SnapshotHolder(Snapshot snapshot, ByteSource snapshotBytes) {
- this.lastIncludedTerm = snapshot.getLastAppliedTerm();
- this.lastIncludedIndex = snapshot.getLastAppliedIndex();
+ SnapshotHolder(final Snapshot snapshot, final ByteSource snapshotBytes) {
+ lastIncludedTerm = snapshot.getLastAppliedTerm();
+ lastIncludedIndex = snapshot.getLastAppliedIndex();
this.snapshotBytes = snapshotBytes;
}