import akka.actor.ActorRef;
import com.google.common.annotations.VisibleForTesting;
-import com.google.protobuf.ByteString;
import java.util.ArrayList;
import org.opendaylight.controller.cluster.raft.RaftActorContext;
import org.opendaylight.controller.cluster.raft.RaftState;
import org.opendaylight.controller.cluster.raft.Snapshot;
import org.opendaylight.controller.cluster.raft.base.messages.ApplySnapshot;
import org.opendaylight.controller.cluster.raft.base.messages.ElectionTimeout;
+import org.opendaylight.controller.cluster.raft.base.messages.FollowerInitialSyncUpStatus;
import org.opendaylight.controller.cluster.raft.messages.AppendEntries;
import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
import org.opendaylight.controller.cluster.raft.messages.InstallSnapshot;
*/
public class Follower extends AbstractRaftActorBehavior {
+
+
private SnapshotTracker snapshotTracker = null;
+ private final InitialSyncStatusTracker initialSyncStatusTracker;
+
public Follower(RaftActorContext context) {
super(context, RaftState.Follower);
- scheduleElection(electionDuration());
+ initialSyncStatusTracker = new InitialSyncStatusTracker(context.getActor());
+
+ if(context.getRaftPolicy().automaticElectionsEnabled()) {
+ if (context.getPeerAddresses().isEmpty()) {
+ actor().tell(ELECTION_TIMEOUT, actor());
+ } else {
+ scheduleElection(electionDuration());
+ }
+ }
+
}
private boolean isLogEntryPresent(long index){
return -1;
}
+ private void updateInitialSyncStatus(long currentLeaderCommit, String leaderId){
+ initialSyncStatusTracker.update(leaderId, currentLeaderCommit, context.getCommitIndex());
+ }
+
@Override protected RaftActorBehavior handleAppendEntries(ActorRef sender,
AppendEntries appendEntries) {
// to make it easier to read. Before refactoring ensure tests
// cover the code properly
- // 1. Reply false if term < currentTerm (§5.1)
- // This is handled in the appendEntries method of the base class
-
- // If we got here then we do appear to be talking to the leader
- leaderId = appendEntries.getLeaderId();
+ if (snapshotTracker != null) {
+ // if snapshot install is in progress, follower should just acknowledge append entries with a reply.
+ AppendEntriesReply reply = new AppendEntriesReply(context.getId(), currentTerm(), true,
+ lastIndex(), lastTerm(), context.getPayloadVersion());
- // 2. Reply false if log doesn’t contain an entry at prevLogIndex
- // whose term matches prevLogTerm (§5.3)
+ if(LOG.isDebugEnabled()) {
+ LOG.debug("{}: snapshot install is in progress, replying immediately with {}", logName(), reply);
+ }
+ sender.tell(reply, actor());
- long prevLogTerm = getLogEntryTerm(appendEntries.getPrevLogIndex());
- boolean prevEntryPresent = isLogEntryPresent(appendEntries.getPrevLogIndex());
+ return this;
+ }
+ // If we got here then we do appear to be talking to the leader
+ leaderId = appendEntries.getLeaderId();
- boolean outOfSync = true;
+ setLeaderPayloadVersion(appendEntries.getPayloadVersion());
+ updateInitialSyncStatus(appendEntries.getLeaderCommit(), appendEntries.getLeaderId());
// First check if the logs are in sync or not
long lastIndex = lastIndex();
- if (lastIndex == -1 && appendEntries.getPrevLogIndex() != -1) {
-
- // The follower's log is out of sync because the leader does have
- // an entry at prevLogIndex and this follower has no entries in
- // it's log.
-
- LOG.debug("{}: The followers log is empty and the senders prevLogIndex is {}",
- logName(), appendEntries.getPrevLogIndex());
- } else if (lastIndex > -1 && appendEntries.getPrevLogIndex() != -1 && !prevEntryPresent) {
- // The follower's log is out of sync because the Leader's
- // prevLogIndex entry was not found in it's log
-
- LOG.debug("{}: The log is not empty but the prevLogIndex {} was not found in it",
- logName(), appendEntries.getPrevLogIndex());
- } else if (lastIndex > -1 && prevEntryPresent && prevLogTerm != appendEntries.getPrevLogTerm()) {
-
- // The follower's log is out of sync because the Leader's
- // prevLogIndex entry does exist in the follower's log but it has
- // a different term in it
-
- LOG.debug(
- "{}: Cannot append entries because previous entry term {} is not equal to append entries prevLogTerm {}",
- logName(), prevLogTerm, appendEntries.getPrevLogTerm());
- } else {
- outOfSync = false;
- }
-
- if (outOfSync) {
+ if (isOutOfSync(appendEntries)) {
// We found that the log was out of sync so just send a negative
// reply and return
logName(), lastIndex, lastTerm());
sender.tell(new AppendEntriesReply(context.getId(), currentTerm(), false, lastIndex,
- lastTerm()), actor());
+ lastTerm(), context.getPayloadVersion()), actor());
return this;
}
}
AppendEntriesReply reply = new AppendEntriesReply(context.getId(), currentTerm(), true,
- lastIndex, lastTerm());
+ lastIndex, lastTerm(), context.getPayloadVersion());
if(LOG.isTraceEnabled()) {
LOG.trace("{}: handleAppendEntries returning : {}", logName(), reply);
sender.tell(reply, actor());
- if (!context.isSnapshotCaptureInitiated()) {
+ if (!context.getSnapshotManager().isCapturing()) {
super.performSnapshotWithoutCapture(appendEntries.getReplicatedToAllIndex());
}
return this;
}
+ private boolean isOutOfSync(AppendEntries appendEntries) {
+
+ long prevLogTerm = getLogEntryTerm(appendEntries.getPrevLogIndex());
+ boolean prevEntryPresent = isLogEntryPresent(appendEntries.getPrevLogIndex());
+ long lastIndex = lastIndex();
+ int numLogEntries = appendEntries.getEntries() != null ? appendEntries.getEntries().size() : 0;
+ boolean outOfSync = true;
+
+ if (lastIndex == -1 && appendEntries.getPrevLogIndex() != -1) {
+
+ // The follower's log is out of sync because the leader does have
+ // an entry at prevLogIndex and this follower has no entries in
+ // it's log.
+
+ LOG.debug("{}: The followers log is empty and the senders prevLogIndex is {}",
+ logName(), appendEntries.getPrevLogIndex());
+ } else if (lastIndex > -1 && appendEntries.getPrevLogIndex() != -1 && !prevEntryPresent) {
+
+ // The follower's log is out of sync because the Leader's
+ // prevLogIndex entry was not found in it's log
+
+ LOG.debug("{}: The log is not empty but the prevLogIndex {} was not found in it",
+ logName(), appendEntries.getPrevLogIndex());
+ } else if (lastIndex > -1 && prevEntryPresent && prevLogTerm != appendEntries.getPrevLogTerm()) {
+
+ // The follower's log is out of sync because the Leader's
+ // prevLogIndex entry does exist in the follower's log but it has
+ // a different term in it
+
+ LOG.debug(
+ "{}: Cannot append entries because previous entry term {} is not equal to append entries prevLogTerm {}",
+ logName(), prevLogTerm, appendEntries.getPrevLogTerm());
+ } else if(appendEntries.getPrevLogIndex() == -1 && appendEntries.getPrevLogTerm() == -1
+ && appendEntries.getReplicatedToAllIndex() != -1
+ && !isLogEntryPresent(appendEntries.getReplicatedToAllIndex())) {
+ // This append entry comes from a leader who has it's log aggressively trimmed and so does not have
+ // the previous entry in it's in-memory journal
+
+ LOG.debug(
+ "{}: Cannot append entries because the replicatedToAllIndex {} does not appear to be in the in-memory journal",
+ logName(), appendEntries.getReplicatedToAllIndex());
+ } else if(appendEntries.getPrevLogIndex() == -1 && appendEntries.getPrevLogTerm() == -1
+ && appendEntries.getReplicatedToAllIndex() != -1 && numLogEntries > 0 &&
+ !isLogEntryPresent(appendEntries.getEntries().get(0).getIndex() - 1)){
+ LOG.debug(
+ "{}: Cannot append entries because the calculated previousIndex {} was not found in the in-memory journal",
+ logName(), appendEntries.getEntries().get(0).getIndex() - 1);
+ } else {
+ outOfSync = false;
+ }
+ return outOfSync;
+ }
+
@Override protected RaftActorBehavior handleAppendEntriesReply(ActorRef sender,
AppendEntriesReply appendEntriesReply) {
return this;
private void handleInstallSnapshot(ActorRef sender, InstallSnapshot installSnapshot) {
-
LOG.debug("{}: InstallSnapshot received from leader {}, datasize: {} , Chunk: {}/{}",
logName(), installSnapshot.getLeaderId(), installSnapshot.getData().size(),
installSnapshot.getChunkIndex(), installSnapshot.getTotalChunks());
snapshotTracker = new SnapshotTracker(LOG, installSnapshot.getTotalChunks());
}
+ updateInitialSyncStatus(installSnapshot.getLastIncludedIndex(), installSnapshot.getLeaderId());
+
try {
if(snapshotTracker.addChunk(installSnapshot.getChunkIndex(), installSnapshot.getData(),
installSnapshot.getLastChunkHashCode())){
}
}
- @Override public void close() throws Exception {
+ @Override
+ public void close() throws Exception {
stopElection();
}
@VisibleForTesting
- ByteString getSnapshotChunksCollected(){
- return snapshotTracker != null ? snapshotTracker.getCollectedChunks() : ByteString.EMPTY;
+ SnapshotTracker getSnapshotTracker(){
+ return snapshotTracker;
+ }
+
+ private class InitialSyncStatusTracker {
+
+ private static final long INVALID_LOG_INDEX = -2L;
+ private long initialLeaderCommit = INVALID_LOG_INDEX;
+ private boolean initialSyncUpDone = false;
+ private String syncedLeaderId = null;
+ private final ActorRef actor;
+
+ public InitialSyncStatusTracker(ActorRef actor) {
+ this.actor = actor;
+ }
+
+ public void update(String leaderId, long leaderCommit, long commitIndex){
+
+ if(!leaderId.equals(syncedLeaderId)){
+ initialSyncUpDone = false;
+ initialLeaderCommit = INVALID_LOG_INDEX;
+ syncedLeaderId = leaderId;
+ }
+
+ if(!initialSyncUpDone){
+ if(initialLeaderCommit == INVALID_LOG_INDEX){
+ actor.tell(new FollowerInitialSyncUpStatus(false, getId()), ActorRef.noSender());
+ initialLeaderCommit = leaderCommit;
+ } else if(commitIndex >= initialLeaderCommit){
+ actor.tell(new FollowerInitialSyncUpStatus(true, getId()), ActorRef.noSender());
+ initialSyncUpDone = true;
+ }
+ }
+ }
}
}
Code Review / controller.git / blobdiff