import org.opendaylight.controller.cluster.raft.behaviors.RaftActorBehavior;
import org.slf4j.Logger;
+/**
+ * Manages the capturing of snapshots for a RaftActor.
+ *
+ * @author Moiz Raja
+ * @author Thomas Pantelis
+ */
public class SnapshotManager implements SnapshotState {
private final SnapshotState IDLE = new Idle();
private final SnapshotState PERSISTING = new Persisting();
private final SnapshotState CREATING = new Creating();
- private final Logger LOG;
+ private final Logger log;
private final RaftActorContext context;
private final LastAppliedTermInformationReader lastAppliedTermInformationReader =
new LastAppliedTermInformationReader();
private ApplySnapshot applySnapshot;
private Consumer<byte[]> applySnapshotProcedure;
+ /**
+ * Constructs an instance.
+ *
+ * @param context the RaftActorContext
+ * @param logger the Logger
+ */
public SnapshotManager(RaftActorContext context, Logger logger) {
this.context = context;
- this.LOG = logger;
+ this.log = logger;
}
public boolean isApplying() {
return captureSnapshot;
}
- private boolean hasFollowers(){
+ private boolean hasFollowers() {
return context.hasFollowers();
}
- private String persistenceId(){
+ private String persistenceId() {
return context.getId();
}
+ /**
+ * Constructs a CaptureSnapshot instance.
+ *
+ * @param lastLogEntry the last log entry for the snapshot.
+ * @param replicatedToAllIndex the index of the last entry replicated to all followers.
+ * @param installSnapshotInitiated true if snapshot is initiated to install on a follower.
+ * @return a new CaptureSnapshot instance.
+ */
public CaptureSnapshot newCaptureSnapshot(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex,
boolean installSnapshotInitiated) {
TermInformationReader lastAppliedTermInfoReader =
long lastLogEntryIndex = lastAppliedIndex;
long lastLogEntryTerm = lastAppliedTerm;
- if(lastLogEntry != null) {
+ if (lastLogEntry != null) {
lastLogEntryIndex = lastLogEntry.getIndex();
lastLogEntryTerm = lastLogEntry.getTerm();
} else {
- LOG.debug("{}: Capturing Snapshot : lastLogEntry is null. Using lastAppliedIndex {} and lastAppliedTerm {} instead.",
+ log.debug("{}: Capturing Snapshot : lastLogEntry is null. Using lastAppliedIndex {} and lastAppliedTerm {} instead.",
persistenceId(), lastAppliedIndex, lastAppliedTerm);
}
@Override
public boolean capture(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex) {
- LOG.debug("capture should not be called in state {}", this);
+ log.debug("capture should not be called in state {}", this);
return false;
}
@Override
- public boolean captureToInstall(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex, String targetFollower) {
- LOG.debug("captureToInstall should not be called in state {}", this);
+ public boolean captureToInstall(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex,
+ String targetFollower) {
+ log.debug("captureToInstall should not be called in state {}", this);
return false;
}
@Override
public void apply(ApplySnapshot snapshot) {
- LOG.debug("apply should not be called in state {}", this);
+ log.debug("apply should not be called in state {}", this);
}
@Override
public void persist(final byte[] snapshotBytes, final long totalMemory) {
- LOG.debug("persist should not be called in state {}", this);
+ log.debug("persist should not be called in state {}", this);
}
@Override
public void commit(final long sequenceNumber, long timeStamp) {
- LOG.debug("commit should not be called in state {}", this);
+ log.debug("commit should not be called in state {}", this);
}
@Override
public void rollback() {
- LOG.debug("rollback should not be called in state {}", this);
+ log.debug("rollback should not be called in state {}", this);
}
@Override
public long trimLog(final long desiredTrimIndex) {
- LOG.debug("trimLog should not be called in state {}", this);
+ log.debug("trimLog should not be called in state {}", this);
return -1;
}
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));
+ long tempMin = Math.min(desiredTrimIndex, lastApplied > -1 ? lastApplied - 1 : -1);
- if(LOG.isTraceEnabled()) {
- LOG.trace("{}: performSnapshotWithoutCapture: desiredTrimIndex: {}, lastApplied: {}, tempMin: {}",
+ if (log.isTraceEnabled()) {
+ log.trace("{}: performSnapshotWithoutCapture: desiredTrimIndex: {}, lastApplied: {}, tempMin: {}",
persistenceId(), desiredTrimIndex, lastApplied, tempMin);
}
if (tempMin > -1 && context.getReplicatedLog().isPresent(tempMin)) {
- LOG.debug("{}: fakeSnapshot purging log to {} for term {}", persistenceId(), tempMin,
+ log.debug("{}: fakeSnapshot purging log to {} for term {}", persistenceId(), tempMin,
context.getTermInformation().getCurrentTerm());
//use the term of the temp-min, since we check for isPresent, entry will not be null
}
final RaftActorBehavior currentBehavior = context.getCurrentBehavior();
- if(tempMin > currentBehavior.getReplicatedToAllIndex()) {
+ 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 boolean capture(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex, String targetFollower) {
captureSnapshot = newCaptureSnapshot(lastLogEntry, replicatedToAllIndex, targetFollower != null);
- if(captureSnapshot.isInstallSnapshotInitiated()) {
- LOG.info("{}: Initiating snapshot capture {} to install on {}",
+ if (captureSnapshot.isInstallSnapshotInitiated()) {
+ log.info("{}: Initiating snapshot capture {} to install on {}",
persistenceId(), captureSnapshot, targetFollower);
} else {
- LOG.info("{}: Initiating snapshot capture {}", persistenceId(), captureSnapshot);
+ log.info("{}: Initiating snapshot capture {}", persistenceId(), captureSnapshot);
}
lastSequenceNumber = context.getPersistenceProvider().getLastSequenceNumber();
- LOG.debug("{}: lastSequenceNumber prior to capture: {}", persistenceId(), lastSequenceNumber);
+ log.debug("{}: lastSequenceNumber prior to capture: {}", persistenceId(), lastSequenceNumber);
SnapshotManager.this.currentState = CREATING;
createSnapshotProcedure.run();
} catch (Exception e) {
SnapshotManager.this.currentState = IDLE;
- LOG.error("Error creating snapshot", e);
+ log.error("Error creating snapshot", e);
return false;
}
}
@Override
- public boolean captureToInstall(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex, String targetFollower) {
+ public boolean captureToInstall(ReplicatedLogEntry lastLogEntry, long replicatedToAllIndex,
+ String targetFollower) {
return capture(lastLogEntry, replicatedToAllIndex, targetFollower);
}
@Override
- public void apply(ApplySnapshot applySnapshot) {
- SnapshotManager.this.applySnapshot = applySnapshot;
+ public void apply(ApplySnapshot toApply) {
+ SnapshotManager.this.applySnapshot = toApply;
lastSequenceNumber = context.getPersistenceProvider().getLastSequenceNumber();
- LOG.debug("lastSequenceNumber prior to persisting applied snapshot: {}", lastSequenceNumber);
+ log.debug("lastSequenceNumber prior to persisting applied snapshot: {}", lastSequenceNumber);
- context.getPersistenceProvider().saveSnapshot(applySnapshot.getSnapshot());
+ context.getPersistenceProvider().saveSnapshot(toApply.getSnapshot());
SnapshotManager.this.currentState = PERSISTING;
}
context.getPersistenceProvider().saveSnapshot(snapshot);
- LOG.info("{}: Persisting of snapshot done: {}", persistenceId(), snapshot);
+ log.info("{}: Persisting of snapshot done: {}", persistenceId(), snapshot);
- long dataThreshold = totalMemory *
- context.getConfigParams().getSnapshotDataThresholdPercentage() / 100;
+ long dataThreshold = totalMemory * context.getConfigParams().getSnapshotDataThresholdPercentage() / 100;
boolean dataSizeThresholdExceeded = context.getReplicatedLog().dataSize() > dataThreshold;
boolean logSizeExceededSnapshotBatchCount =
final RaftActorBehavior currentBehavior = context.getCurrentBehavior();
if (dataSizeThresholdExceeded || logSizeExceededSnapshotBatchCount) {
- if(LOG.isDebugEnabled()) {
- if(dataSizeThresholdExceeded) {
- LOG.debug("{}: log data size {} exceeds the memory threshold {} - doing snapshotPreCommit with index {}",
+ if (log.isDebugEnabled()) {
+ 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 {}",
+ log.debug("{}: log size {} exceeds the snapshot batch count {} - doing snapshotPreCommit with index {}",
context.getId(), context.getReplicatedLog().size(),
- context.getConfigParams().getSnapshotBatchCount(), captureSnapshot.getLastAppliedIndex());
+ context.getConfigParams().getSnapshotBatchCount(),
+ captureSnapshot.getLastAppliedIndex());
}
}
// Don't reset replicatedToAllIndex to -1 as this may prevent us from trimming the log after an
// install snapshot to a follower.
- if(captureSnapshot.getReplicatedToAllIndex() >= 0) {
+ if (captureSnapshot.getReplicatedToAllIndex() >= 0) {
currentBehavior.setReplicatedToAllIndex(captureSnapshot.getReplicatedToAllIndex());
}
- } else if(captureSnapshot.getReplicatedToAllIndex() != -1){
+ } else if (captureSnapshot.getReplicatedToAllIndex() != -1) {
// clear the log based on replicatedToAllIndex
context.getReplicatedLog().snapshotPreCommit(captureSnapshot.getReplicatedToAllIndex(),
captureSnapshot.getReplicatedToAllTerm());
context.getReplicatedLog().getSnapshotTerm());
}
- LOG.info("{}: Removed in-memory snapshotted entries, adjusted snaphsotIndex: {} " +
- "and term: {}", context.getId(), context.getReplicatedLog().getSnapshotIndex(),
+ 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())
@Override
public void commit(final long sequenceNumber, long timeStamp) {
- LOG.debug("{}: Snapshot success - sequence number: {}", persistenceId(), sequenceNumber);
+ log.debug("{}: Snapshot success - sequence number: {}", persistenceId(), sequenceNumber);
- if(applySnapshot != null) {
+ if (applySnapshot != null) {
try {
Snapshot snapshot = applySnapshot.getSnapshot();
context.setCommitIndex(snapshot.getLastAppliedIndex());
context.getTermInformation().update(snapshot.getElectionTerm(), snapshot.getElectionVotedFor());
- if(snapshot.getServerConfiguration() != null) {
+ if (snapshot.getServerConfiguration() != null) {
context.updatePeerIds(snapshot.getServerConfiguration());
}
- if(snapshot.getState().length > 0 ) {
+ if (snapshot.getState().length > 0 ) {
applySnapshotProcedure.accept(snapshot.getState());
}
applySnapshot.getCallback().onSuccess();
} catch (Exception e) {
- LOG.error("{}: Error applying snapshot", context.getId(), e);
+ log.error("{}: Error applying snapshot", context.getId(), e);
}
} else {
context.getReplicatedLog().snapshotCommit();
@Override
public void rollback() {
// Nothing to rollback if we're applying a snapshot from the leader.
- if(applySnapshot == null) {
+ 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(),
+ 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());
private interface TermInformationReader {
long getIndex();
+
long getTerm();
}
- static class LastAppliedTermInformationReader implements TermInformationReader{
+ static class LastAppliedTermInformationReader implements TermInformationReader {
private long index;
private long term;
- public LastAppliedTermInformationReader init(ReplicatedLog log, long originalIndex,
- ReplicatedLogEntry lastLogEntry, boolean hasFollowers){
+ LastAppliedTermInformationReader init(ReplicatedLog log, long originalIndex, ReplicatedLogEntry lastLogEntry,
+ boolean hasFollowers) {
ReplicatedLogEntry entry = log.get(originalIndex);
this.index = -1L;
this.term = -1L;
if (!hasFollowers) {
- if(lastLogEntry != null) {
+ 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();
} else if (entry != null) {
index = entry.getIndex();
term = entry.getTerm();
- } else if(log.getSnapshotIndex() > -1){
+ } else if (log.getSnapshotIndex() > -1) {
index = log.getSnapshotIndex();
term = log.getSnapshotTerm();
}
}
@Override
- public long getIndex(){
+ public long getIndex() {
return this.index;
}
@Override
- public long getTerm(){
+ public long getTerm() {
return this.term;
}
}
- private static class ReplicatedToAllTermInformationReader implements TermInformationReader{
+ private static class ReplicatedToAllTermInformationReader implements TermInformationReader {
private long index;
private long term;
- ReplicatedToAllTermInformationReader init(ReplicatedLog log, long originalIndex){
+ ReplicatedToAllTermInformationReader init(ReplicatedLog log, long originalIndex) {
ReplicatedLogEntry entry = log.get(originalIndex);
this.index = -1L;
this.term = -1L;
}
@Override
- public long getIndex(){
+ public long getIndex() {
return this.index;
}
@Override
- public long getTerm(){
+ public long getTerm() {
return this.term;
}
}
Code Review / controller.git / blobdiff