import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableMap.Builder;
import com.google.protobuf.ByteString;
import java.io.IOException;
import java.util.ArrayList;
+import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
-import java.util.Set;
+import java.util.Map.Entry;
import java.util.concurrent.TimeUnit;
-import java.util.concurrent.atomic.AtomicLong;
import org.opendaylight.controller.cluster.raft.ClientRequestTracker;
import org.opendaylight.controller.cluster.raft.ClientRequestTrackerImpl;
import org.opendaylight.controller.cluster.raft.FollowerLogInformation;
* set commitIndex = N (§5.3, §5.4).
*/
public abstract class AbstractLeader extends AbstractRaftActorBehavior {
- protected final Map<String, FollowerLogInformation> followerToLog = new HashMap<>();
- protected final Map<String, FollowerToSnapshot> mapFollowerToSnapshot = new HashMap<>();
- protected final Set<String> followers;
+ // The index of the first chunk that is sent when installing a snapshot
+ public static final int FIRST_CHUNK_INDEX = 1;
+
+ // The index that the follower should respond with if it needs the install snapshot to be reset
+ public static final int INVALID_CHUNK_INDEX = -1;
+
+ // This would be passed as the hash code of the last chunk when sending the first chunk
+ public static final int INITIAL_LAST_CHUNK_HASH_CODE = -1;
+
+ private final Map<String, FollowerLogInformation> followerToLog;
+ private final Map<String, FollowerToSnapshot> mapFollowerToSnapshot = new HashMap<>();
private Cancellable heartbeatSchedule = null;
public AbstractLeader(RaftActorContext context) {
super(context);
- followers = context.getPeerAddresses().keySet();
-
- for (String followerId : followers) {
+ final Builder<String, FollowerLogInformation> ftlBuilder = ImmutableMap.builder();
+ for (String followerId : context.getPeerAddresses().keySet()) {
FollowerLogInformation followerLogInformation =
new FollowerLogInformationImpl(followerId,
- new AtomicLong(context.getCommitIndex()),
- new AtomicLong(-1),
+ context.getCommitIndex(), -1,
context.getConfigParams().getElectionTimeOutInterval());
- followerToLog.put(followerId, followerLogInformation);
+ ftlBuilder.put(followerId, followerLogInformation);
}
+ followerToLog = ftlBuilder.build();
leaderId = context.getId();
- if(LOG.isDebugEnabled()) {
- LOG.debug("Election:Leader has following peers: {}", followers);
- }
+ LOG.debug("Election:Leader has following peers: {}", getFollowerIds());
- minReplicationCount = getMajorityVoteCount(followers.size());
+ minReplicationCount = getMajorityVoteCount(getFollowerIds().size());
// the isolated Leader peer count will be 1 less than the majority vote count.
// this is because the vote count has the self vote counted in it
scheduleHeartBeat(new FiniteDuration(0, TimeUnit.SECONDS));
}
+ /**
+ * Return an immutable collection of follower identifiers.
+ *
+ * @return Collection of follower IDs
+ */
+ protected final Collection<String> getFollowerIds() {
+ return followerToLog.keySet();
+ }
+
private Optional<ByteString> getSnapshot() {
return snapshot;
}
"sending snapshot chunk failed, Will retry, Chunk:{}",
reply.getChunkIndex()
);
+
followerToSnapshot.markSendStatus(false);
}
" or Chunk Index in InstallSnapshotReply not matching {} != {}",
followerToSnapshot.getChunkIndex(), reply.getChunkIndex()
);
+
+ if(reply.getChunkIndex() == INVALID_CHUNK_INDEX){
+ // Since the Follower did not find this index to be valid we should reset the follower snapshot
+ // so that Installing the snapshot can resume from the beginning
+ followerToSnapshot.reset();
+ }
}
}
logIndex)
);
- if (followers.size() == 0) {
+ if (followerToLog.isEmpty()) {
context.setCommitIndex(logIndex);
applyLogToStateMachine(logIndex);
} else {
private void sendAppendEntries() {
// Send an AppendEntries to all followers
- for (String followerId : followers) {
+ for (Entry<String, FollowerLogInformation> e : followerToLog.entrySet()) {
+ final String followerId = e.getKey();
ActorSelection followerActor = context.getPeerActorSelection(followerId);
if (followerActor != null) {
*
*/
private void installSnapshotIfNeeded() {
- for (String followerId : followers) {
- ActorSelection followerActor =
- context.getPeerActorSelection(followerId);
+ for (Entry<String, FollowerLogInformation> e : followerToLog.entrySet()) {
+ final ActorSelection followerActor = context.getPeerActorSelection(e.getKey());
- if(followerActor != null) {
- FollowerLogInformation followerLogInformation =
- followerToLog.get(followerId);
-
- long nextIndex = followerLogInformation.getNextIndex().get();
+ if (followerActor != null) {
+ long nextIndex = e.getValue().getNextIndex().get();
if (!context.getReplicatedLog().isPresent(nextIndex) &&
context.getReplicatedLog().isInSnapshot(nextIndex)) {
- LOG.info("{} follower needs a snapshot install", followerId);
+ LOG.info("{} follower needs a snapshot install", e.getKey());
if (snapshot.isPresent()) {
// if a snapshot is present in the memory, most likely another install is in progress
// no need to capture snapshot
- sendSnapshotChunk(followerActor, followerId);
+ sendSnapshotChunk(followerActor, e.getKey());
} else {
initiateCaptureSnapshot();
private void sendInstallSnapshot() {
- for (String followerId : followers) {
- ActorSelection followerActor = context.getPeerActorSelection(followerId);
+ for (Entry<String, FollowerLogInformation> e : followerToLog.entrySet()) {
+ ActorSelection followerActor = context.getPeerActorSelection(e.getKey());
- if(followerActor != null) {
- FollowerLogInformation followerLogInformation = followerToLog.get(followerId);
- long nextIndex = followerLogInformation.getNextIndex().get();
+ if (followerActor != null) {
+ long nextIndex = e.getValue().getNextIndex().get();
if (!context.getReplicatedLog().isPresent(nextIndex) &&
context.getReplicatedLog().isInSnapshot(nextIndex)) {
- sendSnapshotChunk(followerActor, followerId);
+ sendSnapshotChunk(followerActor, e.getKey());
}
}
}
context.getReplicatedLog().getSnapshotTerm(),
getNextSnapshotChunk(followerId,snapshot.get()),
mapFollowerToSnapshot.get(followerId).incrementChunkIndex(),
- mapFollowerToSnapshot.get(followerId).getTotalChunks()
+ mapFollowerToSnapshot.get(followerId).getTotalChunks(),
+ Optional.of(mapFollowerToSnapshot.get(followerId).getLastChunkHashCode())
).toSerializable(),
actor()
);
}
private void sendHeartBeat() {
- if (followers.size() > 0) {
+ if (!followerToLog.isEmpty()) {
sendAppendEntries();
}
}
}
private void scheduleHeartBeat(FiniteDuration interval) {
- if(followers.size() == 0){
+ if (followerToLog.isEmpty()) {
// Optimization - do not bother scheduling a heartbeat as there are
// no followers
return;
private boolean replyStatus = false;
private int chunkIndex;
private int totalChunks;
+ private int lastChunkHashCode = AbstractLeader.INITIAL_LAST_CHUNK_HASH_CODE;
+ private int nextChunkHashCode = AbstractLeader.INITIAL_LAST_CHUNK_HASH_CODE;
public FollowerToSnapshot(ByteString snapshotBytes) {
this.snapshotBytes = snapshotBytes;
- replyReceivedForOffset = -1;
- chunkIndex = 1;
int size = snapshotBytes.size();
totalChunks = ( size / context.getConfigParams().getSnapshotChunkSize()) +
((size % context.getConfigParams().getSnapshotChunkSize()) > 0 ? 1 : 0);
LOG.debug("Snapshot {} bytes, total chunks to send:{}",
size, totalChunks);
}
+ replyReceivedForOffset = -1;
+ chunkIndex = AbstractLeader.FIRST_CHUNK_INDEX;
}
public ByteString getSnapshotBytes() {
// if the chunk sent was successful
replyReceivedForOffset = offset;
replyStatus = true;
+ lastChunkHashCode = nextChunkHashCode;
} else {
// if the chunk sent was failure
replyReceivedForOffset = offset;
LOG.debug("length={}, offset={},size={}",
snapshotLength, start, size);
}
- return getSnapshotBytes().substring(start, start + size);
+ ByteString substring = getSnapshotBytes().substring(start, start + size);
+ nextChunkHashCode = substring.hashCode();
+ return substring;
+ }
+ /**
+ * reset should be called when the Follower needs to be sent the snapshot from the beginning
+ */
+ public void reset(){
+ offset = 0;
+ replyStatus = false;
+ replyReceivedForOffset = offset;
+ chunkIndex = AbstractLeader.FIRST_CHUNK_INDEX;
+ lastChunkHashCode = AbstractLeader.INITIAL_LAST_CHUNK_HASH_CODE;
+ }
+
+ public int getLastChunkHashCode() {
+ return lastChunkHashCode;
}
}
// called from example-actor for printing the follower-states
public String printFollowerStates() {
- StringBuilder sb = new StringBuilder();
- for(FollowerLogInformation followerLogInformation : followerToLog.values()) {
- boolean isFollowerActive = followerLogInformation.isFollowerActive();
- sb.append("{"+followerLogInformation.getId() + " state:" + isFollowerActive + "},");
+ final StringBuilder sb = new StringBuilder();
+ sb.append('[');
+ for (FollowerLogInformation followerLogInformation : followerToLog.values()) {
+ sb.append('{');
+ sb.append(followerLogInformation.getId());
+ sb.append(" state:");
+ sb.append(followerLogInformation.isFollowerActive());
+ sb.append("},");
}
- return "[" + sb.toString() + "]";
+ sb.append(']');
+
+ return sb.toString();
+ }
+
+ @VisibleForTesting
+ public FollowerLogInformation getFollower(String followerId) {
+ return followerToLog.get(followerId);
+ }
+
+ @VisibleForTesting
+ protected void setFollowerSnapshot(String followerId, FollowerToSnapshot snapshot) {
+ mapFollowerToSnapshot.put(followerId, snapshot);
+ }
+
+ @VisibleForTesting
+ public int followerSnapshotSize() {
+ return mapFollowerToSnapshot.size();
}
@VisibleForTesting
- void markFollowerActive(String followerId) {
- followerToLog.get(followerId).markFollowerActive();
+ public int followerLogSize() {
+ return followerToLog.size();
}
}
Code Review / controller.git / blobdiff