import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
+import javax.annotation.Nullable;
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.RaftActorContext;
import org.opendaylight.controller.cluster.raft.RaftState;
import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
-import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshot;
+import org.opendaylight.controller.cluster.raft.Snapshot;
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;
protected final int minIsolatedLeaderPeerCount;
- private Optional<ByteString> snapshot;
+ private Optional<SnapshotHolder> snapshot;
public AbstractLeader(RaftActorContext context) {
super(context, RaftState.Leader);
+ setLeaderPayloadVersion(context.getPayloadVersion());
+
final Builder<String, FollowerLogInformation> ftlBuilder = ImmutableMap.builder();
for (String followerId : context.getPeerAddresses().keySet()) {
FollowerLogInformation followerLogInformation =
*
* @return Collection of follower IDs
*/
- protected final Collection<String> getFollowerIds() {
+ public final Collection<String> getFollowerIds() {
return followerToLog.keySet();
}
@VisibleForTesting
- void setSnapshot(Optional<ByteString> snapshot) {
- this.snapshot = snapshot;
+ void setSnapshot(@Nullable Snapshot snapshot) {
+ if(snapshot != null) {
+ this.snapshot = Optional.of(new SnapshotHolder(snapshot));
+ } else {
+ this.snapshot = Optional.absent();
+ }
}
@Override
}
followerLogInformation.markFollowerActive();
+ followerLogInformation.setPayloadVersion(appendEntriesReply.getPayloadVersion());
boolean updated = false;
if (appendEntriesReply.isSuccess()) {
- updated = followerLogInformation.setMatchIndex(appendEntriesReply.getLogLastIndex());
- updated = followerLogInformation.setNextIndex(appendEntriesReply.getLogLastIndex() + 1) || updated;
-
- if(updated && LOG.isDebugEnabled()) {
- LOG.debug("{}: handleAppendEntriesReply - FollowerLogInformation for {} updated: matchIndex: {}, nextIndex: {}", logName(),
- followerId, followerLogInformation.getMatchIndex(), followerLogInformation.getNextIndex());
- }
+ updated = updateFollowerLogInformation(followerLogInformation, appendEntriesReply);
} else {
LOG.debug("{}: handleAppendEntriesReply: received unsuccessful reply: {}", logName(), appendEntriesReply);
- // TODO: When we find that the follower is out of sync with the
- // Leader we simply decrement that followers next index by 1.
- // Would it be possible to do better than this? The RAFT spec
- // does not explicitly deal with it but may be something for us to
- // think about
+ long followerLastLogIndex = appendEntriesReply.getLogLastIndex();
+ ReplicatedLogEntry followersLastLogEntry = context.getReplicatedLog().get(followerLastLogIndex);
+ if(followerLastLogIndex < 0 || (followersLastLogEntry != null &&
+ followersLastLogEntry.getTerm() == 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.
- followerLogInformation.decrNextIndex();
+ updated = updateFollowerLogInformation(followerLogInformation, appendEntriesReply);
+ } else {
+ // TODO: When we find that the follower is out of sync with the
+ // Leader we simply decrement that followers next index by 1.
+ // Would it be possible to do better than this? The RAFT spec
+ // does not explicitly deal with it but may be something for us to
+ // think about.
+
+ followerLogInformation.decrNextIndex();
+ }
}
// Now figure out if this reply warrants a change in the commitIndex
applyLogToStateMachine(context.getCommitIndex());
}
- if (!context.isSnapshotCaptureInitiated()) {
+ if (!context.getSnapshotManager().isCapturing()) {
purgeInMemoryLog();
}
return this;
}
+ private boolean updateFollowerLogInformation(FollowerLogInformation followerLogInformation,
+ AppendEntriesReply appendEntriesReply) {
+ boolean updated = followerLogInformation.setMatchIndex(appendEntriesReply.getLogLastIndex());
+ updated = followerLogInformation.setNextIndex(appendEntriesReply.getLogLastIndex() + 1) || updated;
+
+ if(updated && LOG.isDebugEnabled()) {
+ LOG.debug("{}: handleAppendEntriesReply - FollowerLogInformation for {} updated: matchIndex: {}, nextIndex: {}",
+ logName(), followerLogInformation.getId(), followerLogInformation.getMatchIndex(),
+ followerLogInformation.getNextIndex());
+ }
+ return updated;
+ }
+
private void purgeInMemoryLog() {
//find the lowest index across followers which has been replicated to all.
// lastApplied if there are no followers, so that we keep clearing the log for single-node
} else if(message instanceof SendInstallSnapshot) {
// received from RaftActor
- setSnapshot(Optional.of(((SendInstallSnapshot) message).getSnapshot()));
+ setSnapshot(((SendInstallSnapshot) message).getSnapshot());
sendInstallSnapshot();
} else if (message instanceof Replicate) {
);
}
- followerLogInformation.setMatchIndex(
- context.getReplicatedLog().getSnapshotIndex());
- followerLogInformation.setNextIndex(
- context.getReplicatedLog().getSnapshotIndex() + 1);
+ long followerMatchIndex = snapshot.get().getLastIncludedIndex();
+ followerLogInformation.setMatchIndex(followerMatchIndex);
+ followerLogInformation.setNextIndex(followerMatchIndex + 1);
mapFollowerToSnapshot.remove(followerId);
LOG.debug("{}: follower: {}, matchIndex set to {}, nextIndex set to {}",
if (mapFollowerToSnapshot.isEmpty()) {
// once there are no pending followers receiving snapshots
// we can remove snapshot from the memory
- setSnapshot(Optional.<ByteString>absent());
+ setSnapshot(null);
}
wasLastChunk = true;
followerToSnapshot.markSendStatus(false);
}
- if (wasLastChunk && !context.isSnapshotCaptureInitiated()) {
+ if (wasLastChunk && !context.getSnapshotManager().isCapturing()) {
// Since the follower is now caught up try to purge the log.
purgeInMemoryLog();
} else if (!wasLastChunk && followerToSnapshot.canSendNextChunk()) {
if (followerActor != null) {
long followerNextIndex = followerLogInformation.getNextIndex();
boolean isFollowerActive = followerLogInformation.isFollowerActive();
+ boolean sendAppendEntries = false;
+ List<ReplicatedLogEntry> entries = Collections.emptyList();
if (mapFollowerToSnapshot.get(followerId) != null) {
// if install snapshot is in process , then sent next chunk if possible
sendSnapshotChunk(followerActor, followerId);
} else if(sendHeartbeat) {
// we send a heartbeat even if we have not received a reply for the last chunk
- sendAppendEntriesToFollower(followerActor, followerLogInformation.getNextIndex(),
- Collections.<ReplicatedLogEntry>emptyList(), followerId);
+ sendAppendEntries = true;
}
} else {
long leaderLastIndex = context.getReplicatedLog().lastIndex();
long leaderSnapShotIndex = context.getReplicatedLog().getSnapshotIndex();
if((!isHeartbeat && LOG.isDebugEnabled()) || LOG.isTraceEnabled()) {
- LOG.debug("{}: Checking sendAppendEntries for follower {}, followerNextIndex {}, leaderLastIndex: {}, leaderSnapShotIndex: {}",
- logName(), followerId, followerNextIndex, leaderLastIndex, leaderSnapShotIndex);
+ LOG.debug("{}: Checking sendAppendEntries for follower {}: active: {}, followerNextIndex: {}, leaderLastIndex: {}, leaderSnapShotIndex: {}",
+ logName(), followerId, isFollowerActive, followerNextIndex, leaderLastIndex, leaderSnapShotIndex);
}
if (isFollowerActive && context.getReplicatedLog().isPresent(followerNextIndex)) {
LOG.debug("{}: sendAppendEntries: {} is present for follower {}", logName(),
followerNextIndex, followerId);
- // FIXME : Sending one entry at a time
- final List<ReplicatedLogEntry> entries = context.getReplicatedLog().getFrom(followerNextIndex, 1);
-
- sendAppendEntriesToFollower(followerActor, followerNextIndex, entries, followerId);
-
+ if(followerLogInformation.okToReplicate()) {
+ // Try to send all the entries in the journal but not exceeding the max data size
+ // for a single AppendEntries message.
+ int maxEntries = (int) context.getReplicatedLog().size();
+ entries = context.getReplicatedLog().getFrom(followerNextIndex, maxEntries,
+ context.getConfigParams().getSnapshotChunkSize());
+ sendAppendEntries = true;
+ }
} else if (isFollowerActive && followerNextIndex >= 0 &&
- leaderLastIndex > followerNextIndex && !context.isSnapshotCaptureInitiated()) {
+ leaderLastIndex > followerNextIndex && !context.getSnapshotManager().isCapturing()) {
// if the followers next index is not present in the leaders log, and
// if the follower is just not starting and if leader's index is more than followers index
// then snapshot should be sent
}
// Send heartbeat to follower whenever install snapshot is initiated.
- sendAppendEntriesToFollower(followerActor, followerLogInformation.getNextIndex(),
- Collections.<ReplicatedLogEntry>emptyList(), followerId);
-
+ sendAppendEntries = true;
initiateCaptureSnapshot(followerId, followerNextIndex);
} else if(sendHeartbeat) {
- //we send an AppendEntries, even if the follower is inactive
+ // we send an AppendEntries, even if the follower is inactive
// in-order to update the followers timestamp, in case it becomes active again
- sendAppendEntriesToFollower(followerActor, followerLogInformation.getNextIndex(),
- Collections.<ReplicatedLogEntry>emptyList(), followerId);
+ sendAppendEntries = true;
}
}
+
+ if(sendAppendEntries) {
+ sendAppendEntriesToFollower(followerActor, followerNextIndex,
+ entries, followerId);
+ }
}
}
AppendEntries appendEntries = new AppendEntries(currentTerm(), context.getId(),
prevLogIndex(followerNextIndex),
prevLogTerm(followerNextIndex), entries,
- context.getCommitIndex(), super.getReplicatedToAllIndex());
+ context.getCommitIndex(), super.getReplicatedToAllIndex(), context.getPayloadVersion());
if(!entries.isEmpty() || LOG.isTraceEnabled()) {
LOG.debug("{}: Sending AppendEntries to follower {}: {}", logName(), followerId,
final ActorSelection followerActor = context.getPeerActorSelection(followerId);
sendSnapshotChunk(followerActor, followerId);
- } else if (!context.isSnapshotCaptureInitiated()) {
- ReplicatedLogEntry lastAppliedEntry = context.getReplicatedLog().get(context.getLastApplied());
- long lastAppliedIndex = -1;
- long lastAppliedTerm = -1;
-
- if (lastAppliedEntry != null) {
- lastAppliedIndex = lastAppliedEntry.getIndex();
- lastAppliedTerm = lastAppliedEntry.getTerm();
- } else if (context.getReplicatedLog().getSnapshotIndex() > -1) {
- lastAppliedIndex = context.getReplicatedLog().getSnapshotIndex();
- lastAppliedTerm = context.getReplicatedLog().getSnapshotTerm();
- }
-
- boolean isInstallSnapshotInitiated = true;
- long replicatedToAllIndex = super.getReplicatedToAllIndex();
- ReplicatedLogEntry replicatedToAllEntry = context.getReplicatedLog().get(replicatedToAllIndex);
-
- CaptureSnapshot captureSnapshot = new CaptureSnapshot(
- lastIndex(), lastTerm(), lastAppliedIndex, lastAppliedTerm,
- (replicatedToAllEntry != null ? replicatedToAllEntry.getIndex() : -1),
- (replicatedToAllEntry != null ? replicatedToAllEntry.getTerm() : -1),
- isInstallSnapshotInitiated);
-
- if(LOG.isDebugEnabled()) {
- LOG.debug("{}: Initiating install snapshot to follower {}: {}", logName(), followerId,
- captureSnapshot);
- }
-
- actor().tell(captureSnapshot, actor());
- context.setSnapshotCaptureInitiated(true);
+ } else {
+ context.getSnapshotManager().captureToInstall(context.getReplicatedLog().last(),
+ this.getReplicatedToAllIndex(), followerId);
}
}
}
private void sendSnapshotChunk(ActorSelection followerActor, String followerId) {
try {
if (snapshot.isPresent()) {
- ByteString nextSnapshotChunk = getNextSnapshotChunk(followerId,snapshot.get());
+ ByteString nextSnapshotChunk = getNextSnapshotChunk(followerId, snapshot.get().getSnapshotBytes());
// Note: the previous call to getNextSnapshotChunk has the side-effect of adding
// followerId to the followerToSnapshot map.
followerActor.tell(
new InstallSnapshot(currentTerm(), context.getId(),
- context.getReplicatedLog().getSnapshotIndex(),
- context.getReplicatedLog().getSnapshotTerm(),
+ snapshot.get().getLastIncludedIndex(),
+ snapshot.get().getLastIncludedTerm(),
nextSnapshotChunk,
followerToSnapshot.incrementChunkIndex(),
followerToSnapshot.getTotalChunks(),
public int followerLogSize() {
return followerToLog.size();
}
+
+ private static class SnapshotHolder {
+ private final long lastIncludedTerm;
+ private final long lastIncludedIndex;
+ private final ByteString snapshotBytes;
+
+ SnapshotHolder(Snapshot snapshot) {
+ this.lastIncludedTerm = snapshot.getLastAppliedTerm();
+ this.lastIncludedIndex = snapshot.getLastAppliedIndex();
+ this.snapshotBytes = ByteString.copyFrom(snapshot.getState());
+ }
+
+ long getLastIncludedTerm() {
+ return lastIncludedTerm;
+ }
+
+ long getLastIncludedIndex() {
+ return lastIncludedIndex;
+ }
+
+ ByteString getSnapshotBytes() {
+ return snapshotBytes;
+ }
+ }
}