package org.opendaylight.controller.cluster.raft;
-import akka.japi.Procedure;
import akka.persistence.SnapshotSelectionCriteria;
-import com.google.protobuf.ByteString;
-import org.opendaylight.controller.cluster.DataPersistenceProvider;
+import com.google.common.annotations.VisibleForTesting;
+import java.util.List;
+import java.util.function.Consumer;
+import org.opendaylight.controller.cluster.raft.base.messages.ApplySnapshot;
import org.opendaylight.controller.cluster.raft.base.messages.CaptureSnapshot;
import org.opendaylight.controller.cluster.raft.base.messages.SendInstallSnapshot;
+import org.opendaylight.controller.cluster.raft.base.messages.SnapshotComplete;
import org.opendaylight.controller.cluster.raft.behaviors.RaftActorBehavior;
import org.slf4j.Logger;
public class SnapshotManager implements SnapshotState {
-
private final SnapshotState IDLE = new Idle();
- private final SnapshotState CAPTURING = new Capturing();
private final SnapshotState PERSISTING = new Persisting();
private final SnapshotState CREATING = new Creating();
private SnapshotState currentState = IDLE;
private CaptureSnapshot captureSnapshot;
+ private long lastSequenceNumber = -1;
+
+ private Runnable createSnapshotProcedure;
+
+ private ApplySnapshot applySnapshot;
+ private Consumer<byte[]> applySnapshotProcedure;
public SnapshotManager(RaftActorContext context, Logger logger) {
this.context = context;
this.LOG = logger;
}
+ public boolean isApplying() {
+ return applySnapshot != null;
+ }
+
@Override
public boolean isCapturing() {
return currentState.isCapturing();
}
@Override
- public void create(Procedure<Void> callback) {
- currentState.create(callback);
+ public void apply(ApplySnapshot snapshot) {
+ currentState.apply(snapshot);
}
@Override
- public void persist(DataPersistenceProvider persistenceProvider, byte[] snapshotBytes,
- RaftActorBehavior currentBehavior, long totalMemory) {
- currentState.persist(persistenceProvider, snapshotBytes, currentBehavior, totalMemory);
+ public void persist(final byte[] snapshotBytes, final long totalMemory) {
+ currentState.persist(snapshotBytes, totalMemory);
}
@Override
- public void commit(DataPersistenceProvider persistenceProvider, long sequenceNumber) {
- currentState.commit(persistenceProvider, sequenceNumber);
+ public void commit(final long sequenceNumber) {
+ currentState.commit(sequenceNumber);
}
@Override
}
@Override
- public long trimLog(long desiredTrimIndex, RaftActorBehavior currentBehavior) {
- return currentState.trimLog(desiredTrimIndex, currentBehavior);
+ public long trimLog(final long desiredTrimIndex) {
+ return currentState.trimLog(desiredTrimIndex);
+ }
+
+ public void setCreateSnapshotRunnable(Runnable createSnapshotProcedure) {
+ this.createSnapshotProcedure = createSnapshotProcedure;
+ }
+
+ public void setApplySnapshotConsumer(Consumer<byte[]> applySnapshotProcedure) {
+ this.applySnapshotProcedure = applySnapshotProcedure;
+ }
+
+ public long getLastSequenceNumber() {
+ return lastSequenceNumber;
+ }
+
+ @VisibleForTesting
+ public CaptureSnapshot getCaptureSnapshot() {
+ return captureSnapshot;
}
private boolean hasFollowers(){
- return context.getPeerAddresses().keySet().size() > 0;
+ return context.hasFollowers();
}
private String persistenceId(){
return context.getId();
}
+ public CaptureSnapshot newCaptureSnapshot(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex,
+ boolean installSnapshotInitiated) {
+ TermInformationReader lastAppliedTermInfoReader =
+ lastAppliedTermInformationReader.init(context.getReplicatedLog(), context.getLastApplied(),
+ lastLogEntry, hasFollowers());
+
+ long lastAppliedIndex = lastAppliedTermInfoReader.getIndex();
+ long lastAppliedTerm = lastAppliedTermInfoReader.getTerm();
+
+ TermInformationReader replicatedToAllTermInfoReader =
+ replicatedToAllTermInformationReader.init(context.getReplicatedLog(), replicatedToAllIndex);
+
+ long newReplicatedToAllIndex = replicatedToAllTermInfoReader.getIndex();
+ long newReplicatedToAllTerm = replicatedToAllTermInfoReader.getTerm();
+
+ List<ReplicatedLogEntry> unAppliedEntries = context.getReplicatedLog().getFrom(lastAppliedIndex + 1);
+
+ long lastLogEntryIndex = lastAppliedIndex;
+ long lastLogEntryTerm = lastAppliedTerm;
+ if(lastLogEntry != null) {
+ lastLogEntryIndex = lastLogEntry.getIndex();
+ lastLogEntryTerm = lastLogEntry.getTerm();
+ } else {
+ LOG.debug("{}: Capturing Snapshot : lastLogEntry is null. Using lastAppliedIndex {} and lastAppliedTerm {} instead.",
+ persistenceId(), lastAppliedIndex, lastAppliedTerm);
+ }
+
+ return new CaptureSnapshot(lastLogEntryIndex, lastLogEntryTerm, lastAppliedIndex, lastAppliedTerm,
+ newReplicatedToAllIndex, newReplicatedToAllTerm, unAppliedEntries, installSnapshotInitiated);
+ }
+
private class AbstractSnapshotState implements SnapshotState {
@Override
public boolean isCapturing() {
- return false;
+ return true;
}
@Override
}
@Override
- public void create(Procedure<Void> callback) {
- LOG.debug("create should not be called in state {}", this);
+ public void apply(ApplySnapshot snapshot) {
+ LOG.debug("apply should not be called in state {}", this);
}
@Override
- public void persist(DataPersistenceProvider persistenceProvider, byte[] snapshotBytes,
- RaftActorBehavior currentBehavior, long totalMemory) {
+ public void persist(final byte[] snapshotBytes, final long totalMemory) {
LOG.debug("persist should not be called in state {}", this);
}
@Override
- public void commit(DataPersistenceProvider persistenceProvider, long sequenceNumber) {
+ public void commit(final long sequenceNumber) {
LOG.debug("commit should not be called in state {}", this);
}
}
@Override
- public long trimLog(long desiredTrimIndex, RaftActorBehavior currentBehavior) {
+ public long trimLog(final long desiredTrimIndex) {
LOG.debug("trimLog should not be called in state {}", this);
return -1;
}
- protected long doTrimLog(long desiredTrimIndex, RaftActorBehavior currentBehavior){
+ protected long doTrimLog(final long desiredTrimIndex) {
// we would want to keep the lastApplied as its used while capturing snapshots
long lastApplied = context.getLastApplied();
long tempMin = Math.min(desiredTrimIndex, (lastApplied > -1 ? lastApplied - 1 : -1));
context.getReplicatedLog().snapshotPreCommit(tempMin, entry.getTerm());
context.getReplicatedLog().snapshotCommit();
return tempMin;
- } else if(tempMin > currentBehavior.getReplicatedToAllIndex()) {
+ }
+
+ final RaftActorBehavior currentBehavior = context.getCurrentBehavior();
+ if(tempMin > currentBehavior.getReplicatedToAllIndex()) {
// It's possible a follower was lagging and an install snapshot advanced its match index past
// the current replicatedToAllIndex. Since the follower is now caught up we should advance the
// replicatedToAllIndex (to tempMin). The fact that tempMin wasn't found in the log is likely
private class Idle extends AbstractSnapshotState {
- private boolean capture(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex, String targetFollower) {
- TermInformationReader lastAppliedTermInfoReader =
- lastAppliedTermInformationReader.init(context.getReplicatedLog(), context.getLastApplied(),
- lastLogEntry, hasFollowers());
+ @Override
+ public boolean isCapturing() {
+ return false;
+ }
- long lastAppliedIndex = lastAppliedTermInfoReader.getIndex();
- long lastAppliedTerm = lastAppliedTermInfoReader.getTerm();
+ private boolean capture(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex, String targetFollower) {
+ captureSnapshot = newCaptureSnapshot(lastLogEntry, replicatedToAllIndex, targetFollower != null);
- TermInformationReader replicatedToAllTermInfoReader =
- replicatedToAllTermInformationReader.init(context.getReplicatedLog(), replicatedToAllIndex);
+ if(captureSnapshot.isInstallSnapshotInitiated()) {
+ LOG.info("{}: Initiating snapshot capture {} to install on {}",
+ persistenceId(), captureSnapshot, targetFollower);
+ } else {
+ LOG.info("{}: Initiating snapshot capture {}", persistenceId(), captureSnapshot);
+ }
- long newReplicatedToAllIndex = replicatedToAllTermInfoReader.getIndex();
- long newReplicatedToAllTerm = replicatedToAllTermInfoReader.getTerm();
+ lastSequenceNumber = context.getPersistenceProvider().getLastSequenceNumber();
- // send a CaptureSnapshot to self to make the expensive operation async.
- captureSnapshot = new CaptureSnapshot(lastLogEntry.getIndex(),
- lastLogEntry.getTerm(), lastAppliedIndex, lastAppliedTerm,
- newReplicatedToAllIndex, newReplicatedToAllTerm, targetFollower!=null);
+ LOG.debug("{}: lastSequenceNumber prior to capture: {}", persistenceId(), lastSequenceNumber);
- SnapshotManager.this.currentState = CAPTURING;
+ SnapshotManager.this.currentState = CREATING;
- if(targetFollower != null){
- LOG.info("{}: Initiating snapshot capture {}", persistenceId(), captureSnapshot);
- } else {
- LOG.info("{}: Initiating snapshot capture {} to install on {}",
- persistenceId(), captureSnapshot, targetFollower);
+ try {
+ createSnapshotProcedure.run();
+ } catch (Exception e) {
+ SnapshotManager.this.currentState = IDLE;
+ LOG.error("Error creating snapshot", e);
+ return false;
}
- context.getActor().tell(captureSnapshot, context.getActor());
-
return true;
}
}
@Override
- public String toString() {
- return "Idle";
- }
+ public void apply(ApplySnapshot applySnapshot) {
+ SnapshotManager.this.applySnapshot = applySnapshot;
- @Override
- public long trimLog(long desiredTrimIndex, RaftActorBehavior currentBehavior) {
- return doTrimLog(desiredTrimIndex, currentBehavior);
- }
- }
+ lastSequenceNumber = context.getPersistenceProvider().getLastSequenceNumber();
- private class Capturing extends AbstractSnapshotState {
+ LOG.debug("lastSequenceNumber prior to persisting applied snapshot: {}", lastSequenceNumber);
- @Override
- public boolean isCapturing() {
- return true;
- }
+ context.getPersistenceProvider().saveSnapshot(applySnapshot.getSnapshot());
- @Override
- public void create(Procedure<Void> callback) {
- try {
- callback.apply(null);
- SnapshotManager.this.currentState = CREATING;
- } catch (Exception e) {
- LOG.error("Unexpected error occurred", e);
- }
+ SnapshotManager.this.currentState = PERSISTING;
}
@Override
public String toString() {
- return "Capturing";
+ return "Idle";
}
+ @Override
+ public long trimLog(final long desiredTrimIndex) {
+ return doTrimLog(desiredTrimIndex);
+ }
}
private class Creating extends AbstractSnapshotState {
@Override
- public boolean isCapturing() {
- return true;
- }
-
- @Override
- public void persist(DataPersistenceProvider persistenceProvider, byte[] snapshotBytes,
- RaftActorBehavior currentBehavior, long totalMemory) {
+ public void persist(final byte[] snapshotBytes, final long totalMemory) {
// create a snapshot object from the state provided and save it
// when snapshot is saved async, SaveSnapshotSuccess is raised.
- Snapshot sn = Snapshot.create(snapshotBytes,
- context.getReplicatedLog().getFrom(captureSnapshot.getLastAppliedIndex() + 1),
+ Snapshot snapshot = Snapshot.create(snapshotBytes,
+ captureSnapshot.getUnAppliedEntries(),
captureSnapshot.getLastIndex(), captureSnapshot.getLastTerm(),
- captureSnapshot.getLastAppliedIndex(), captureSnapshot.getLastAppliedTerm());
+ captureSnapshot.getLastAppliedIndex(), captureSnapshot.getLastAppliedTerm(),
+ context.getTermInformation().getCurrentTerm(),
+ context.getTermInformation().getVotedFor(), context.getPeerServerInfo(true));
- persistenceProvider.saveSnapshot(sn);
+ context.getPersistenceProvider().saveSnapshot(snapshot);
- LOG.info("{}: Persisting of snapshot done:{}", persistenceId(), sn.getLogMessage());
+ LOG.info("{}: Persisting of snapshot done: {}", persistenceId(), snapshot);
long dataThreshold = totalMemory *
context.getConfigParams().getSnapshotDataThresholdPercentage() / 100;
- if (context.getReplicatedLog().dataSize() > dataThreshold) {
+ boolean dataSizeThresholdExceeded = context.getReplicatedLog().dataSize() > dataThreshold;
+ boolean logSizeExceededSnapshotBatchCount =
+ context.getReplicatedLog().size() >= context.getConfigParams().getSnapshotBatchCount();
+
+ final RaftActorBehavior currentBehavior = context.getCurrentBehavior();
+ if (dataSizeThresholdExceeded || logSizeExceededSnapshotBatchCount) {
if(LOG.isDebugEnabled()) {
- LOG.debug("{}: dataSize {} exceeds dataThreshold {} - doing snapshotPreCommit with index {}",
- persistenceId(), context.getReplicatedLog().dataSize(), dataThreshold,
- captureSnapshot.getLastAppliedIndex());
+ if(dataSizeThresholdExceeded) {
+ LOG.debug("{}: log data size {} exceeds the memory threshold {} - doing snapshotPreCommit with index {}",
+ context.getId(), context.getReplicatedLog().dataSize(), dataThreshold,
+ captureSnapshot.getLastAppliedIndex());
+ } else {
+ LOG.debug("{}: log size {} exceeds the snapshot batch count {} - doing snapshotPreCommit with index {}",
+ context.getId(), context.getReplicatedLog().size(),
+ context.getConfigParams().getSnapshotBatchCount(), captureSnapshot.getLastAppliedIndex());
+ }
}
- // if memory is less, clear the log based on lastApplied.
- // this could/should only happen if one of the followers is down
- // as normally we keep removing from the log when its replicated to all.
+ // We either exceeded the memory threshold or the log size exceeded the snapshot batch
+ // count so, to keep the log memory footprint in check, clear the log based on lastApplied.
+ // This could/should only happen if one of the followers is down as normally we keep
+ // removing from the log as entries are replicated to all.
context.getReplicatedLog().snapshotPreCommit(captureSnapshot.getLastAppliedIndex(),
captureSnapshot.getLastAppliedTerm());
context.getReplicatedLog().getSnapshotTerm());
}
- LOG.info("{}: Removed in-memory snapshotted entries, adjusted snaphsotIndex:{} " +
- "and term:{}", persistenceId(), captureSnapshot.getLastAppliedIndex(),
- captureSnapshot.getLastAppliedTerm());
+ LOG.info("{}: Removed in-memory snapshotted entries, adjusted snaphsotIndex: {} " +
+ "and term: {}", context.getId(), context.getReplicatedLog().getSnapshotIndex(),
+ context.getReplicatedLog().getSnapshotTerm());
if (context.getId().equals(currentBehavior.getLeaderId())
&& captureSnapshot.isInstallSnapshotInitiated()) {
// this would be call straight to the leader and won't initiate in serialization
- currentBehavior.handleMessage(context.getActor(), new SendInstallSnapshot(
- ByteString.copyFrom(snapshotBytes)));
+ currentBehavior.handleMessage(context.getActor(), new SendInstallSnapshot(snapshot));
}
captureSnapshot = null;
private class Persisting extends AbstractSnapshotState {
@Override
- public void commit(DataPersistenceProvider persistenceProvider, long sequenceNumber) {
- context.getReplicatedLog().snapshotCommit();
- persistenceProvider.deleteSnapshots(new SnapshotSelectionCriteria(
- sequenceNumber - context.getConfigParams().getSnapshotBatchCount(), 43200000));
+ public void commit(final long sequenceNumber) {
+ LOG.debug("{}: Snapshot success - sequence number: {}", persistenceId(), sequenceNumber);
+
+ if(applySnapshot != null) {
+ try {
+ Snapshot snapshot = applySnapshot.getSnapshot();
+
+ //clears the followers log, sets the snapshot index to ensure adjusted-index works
+ context.setReplicatedLog(ReplicatedLogImpl.newInstance(snapshot, context));
+ context.setLastApplied(snapshot.getLastAppliedIndex());
+ context.setCommitIndex(snapshot.getLastAppliedIndex());
+ context.getTermInformation().update(snapshot.getElectionTerm(), snapshot.getElectionVotedFor());
+
+ if(snapshot.getState().length > 0 ) {
+ applySnapshotProcedure.accept(snapshot.getState());
+ }
+
+ applySnapshot.getCallback().onSuccess();
+ } catch (Exception e) {
+ LOG.error("{}: Error applying snapshot", context.getId(), e);
+ }
+ } else {
+ context.getReplicatedLog().snapshotCommit();
+ }
- persistenceProvider.deleteMessages(sequenceNumber);
+ context.getPersistenceProvider().deleteSnapshots(new SnapshotSelectionCriteria(
+ sequenceNumber - context.getConfigParams().getSnapshotBatchCount(), Long.MAX_VALUE, 0L, 0L));
- SnapshotManager.this.currentState = IDLE;
+ context.getPersistenceProvider().deleteMessages(lastSequenceNumber);
+
+ snapshotComplete();
}
@Override
public void rollback() {
- context.getReplicatedLog().snapshotRollback();
+ // Nothing to rollback if we're applying a snapshot from the leader.
+ if(applySnapshot == null) {
+ context.getReplicatedLog().snapshotRollback();
+
+ LOG.info("{}: Replicated Log rolled back. Snapshot will be attempted in the next cycle." +
+ "snapshotIndex:{}, snapshotTerm:{}, log-size:{}", persistenceId(),
+ context.getReplicatedLog().getSnapshotIndex(),
+ context.getReplicatedLog().getSnapshotTerm(),
+ context.getReplicatedLog().size());
+ } else {
+ applySnapshot.getCallback().onFailure();
+ }
- LOG.info("{}: Replicated Log rolled back. Snapshot will be attempted in the next cycle." +
- "snapshotIndex:{}, snapshotTerm:{}, log-size:{}", persistenceId(),
- context.getReplicatedLog().getSnapshotIndex(),
- context.getReplicatedLog().getSnapshotTerm(),
- context.getReplicatedLog().size());
+ snapshotComplete();
+ }
+ private void snapshotComplete() {
+ lastSequenceNumber = -1;
+ applySnapshot = null;
SnapshotManager.this.currentState = IDLE;
+
+ context.getActor().tell(SnapshotComplete.INSTANCE, context.getActor());
}
@Override
long getTerm();
}
- private static class LastAppliedTermInformationReader implements TermInformationReader{
+ static class LastAppliedTermInformationReader implements TermInformationReader{
private long index;
private long term;
this.term = -1L;
if (!hasFollowers) {
if(lastLogEntry != null) {
+ // since we have persisted the last-log-entry to persistent journal before the capture,
+ // we would want to snapshot from this entry.
index = lastLogEntry.getIndex();
term = lastLogEntry.getTerm();
}
Code Review / controller.git / blobdiff