org.apache.flink.runtime.state.gemini.engine.snapshot.SnapshotManager Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* distributed with this work for additional information
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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.runtime.state.gemini.engine.snapshot;
import org.apache.flink.annotation.VisibleForTesting;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.core.fs.Path;
import org.apache.flink.runtime.state.gemini.engine.GRegionContext;
import org.apache.flink.runtime.state.gemini.engine.GRegionID;
import org.apache.flink.runtime.state.gemini.engine.filecache.PageBatchFlusher;
import org.apache.flink.runtime.state.gemini.engine.page.PageIndex;
import javax.annotation.Nullable;
import java.io.Closeable;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
/**
* SnapshotManager.
*/
public interface SnapshotManager extends Closeable {
/**
* Whether we need to break the lineage. If we need to break the lineage,
* e.g. rescaling case, we would not remember any parental lineage information
* and ensure all data must go into newer snapshot to not depend any older snapshots.
* In a nutshell, when need to break the lineage, that snapshot cannot be a incremental one.
*/
boolean isNeedToBreakLineage();
void setNeedToBreakLineage(boolean needToBreakLineage);
/**
* synchronously method, start a snapshot, will submit a SnapshotHandler to asynchronously run.
*/
Future startSnapshot(BackendSnapshotMeta backendSnapshotMeta);
/**
* complete snapshot successfully or exceptionally.
* @param throwable The throwable for exceptionally complete, and null for successfully.
*/
void endSnapshot(long checkpointId, Throwable throwable);
/**
* finally result of snapshot.
*/
@Nullable
PendingSnapshot getPendingSnapshot(long checkpointId);
/**
* Returns the namespace of this snapshot manager.
*
* Namespace acts as an unique id of this snapshot manager.
* All snapshots generated by this snapshot manager should have the same namespace.
* When restoring, Gemini would use namespace to judge whether this should flush all pages when executing first checkpoint.
*
* @return The namespace of this snapshot manager.
*/
String getNameSpace();
/**
* Min access number of running snapshot.
*/
long getMinRunningSnapshotAccessNumber();
/**
* Get the executorService for snapshot.
*/
ExecutorService getSnapshotExecutor();
/**
* This method is called as a notification once a distributed checkpoint has been completed.
*/
void notifySnapshotComplete(long snapshotID);
/**
* This method is called as a notification once a distributed checkpoint has been aborted.
*/
void notifySnapshotAbort(long snapshotID);
/**
* This method is called as a notification once a distributed checkpoint has been subsumed.
*/
void notifySnapshotSubsume(long snapshotID);
/**
* Restore all snapshots according to the snapshot which DB is restored.
*
* @param snapshotId snapshot which db is restored from.
* @param fileMapping file mapping db is restored from.
* @param restoredBasePath db base path the snapshot used.
* @return all snapshots restored.
*/
Map restore(long snapshotId, Map fileMapping, String restoredBasePath);
/**
* snapshot result.
*/
class PendingSnapshot {
long checkpointId;
long timestamp;
SnapshotCompletableFuture resultFuture;
// table name -> region id -> region meta
private final Map> regionSnapshotMetas;
Path snapshotBasePath;
Path snapshotMetaPath;
@Nullable
Path localSnapshotBasePath;
@Nullable
Path localSnapshotMetaPath;
// mapping table for dfs snapshot.
Map>> fileMapping;
// mapping table for local snapshot.
@Nullable
Map>> localFileMapping;
long accessNumber;
SnapshotOperation snapshotOperation;
SnapshotCompaction snapshotCompaction;
private final SnapshotStat snapshotStat;
private boolean isCanceled;
private DBSnapshotResult dbSnapshotResult;
private CompletableFuture dbSnapshotResultFuture;
/**
* This flusher can only be used in {@link SnapshotManagerImpl#snapshotExecutor}
* so that it's guaranteed to thread safety.
*/
private PageBatchFlusher dfsPageBatchFlusher ;
public PendingSnapshot(
long checkpointId,
long timestamp,
SnapshotCompletableFuture resultFuture,
Path snapshotBasePath,
Path snapshotMetaPath,
Path localSnapshotBasePath,
Path localSnapshotMetaPath,
long accessNumber,
SnapshotOperation snapshotOperation,
PageBatchFlusher dfsPageBatchFlusher) {
this.checkpointId = checkpointId;
this.timestamp = timestamp;
this.resultFuture = resultFuture;
this.snapshotBasePath = snapshotBasePath;
this.snapshotMetaPath = snapshotMetaPath;
this.localSnapshotBasePath = localSnapshotBasePath;
this.localSnapshotMetaPath = localSnapshotMetaPath;
this.accessNumber = accessNumber;
this.snapshotOperation = snapshotOperation;
this.regionSnapshotMetas = new ConcurrentHashMap<>();
this.snapshotStat = new SnapshotStat();
this.isCanceled = false;
this.snapshotCompaction = NoSnapshotCompaction.INSTANCE;
this.dfsPageBatchFlusher = dfsPageBatchFlusher;
this.dbSnapshotResultFuture = new CompletableFuture<>();
}
public long getCheckpointId() {
return checkpointId;
}
public long getTimestamp() {
return timestamp;
}
public SnapshotCompletableFuture getResultFuture() {
return resultFuture;
}
public Path getSnapshotBasePath() {
return snapshotBasePath;
}
public Path getSnapshotMetaPath() {
return snapshotMetaPath;
}
public Path getLocalSnapshotBasePath() {
return localSnapshotBasePath;
}
public Path getLocalSnapshotMetaPath() {
return localSnapshotMetaPath;
}
public long getAccessNumber() {
return accessNumber;
}
public SnapshotOperation getSnapshotOperation() {
return snapshotOperation;
}
public SnapshotCompaction getSnapshotCompaction() {
return snapshotCompaction;
}
public void setSnapshotCompaction(SnapshotCompaction snapshotCompaction) {
this.snapshotCompaction = snapshotCompaction;
}
public void addGRegionSnapshotMeta(
GRegionContext gRegionContext,
PageIndex pageIndex) {
regionSnapshotMetas.computeIfAbsent(gRegionContext.getTableName(), (nothing) -> new ConcurrentHashMap<>())
.put(gRegionContext.getRegionId(), new GRegionSnapshotMeta(
gRegionContext, pageIndex, gRegionContext.getLastSeqId(), gRegionContext.getRemoveAllSeqId()));
}
public Map> getGRegionSnapshotMeta() {
return regionSnapshotMetas;
}
public void setFileMapping(Map>> fileMapping) {
this.fileMapping = fileMapping;
}
public Map>> getFileMapping() {
return fileMapping;
}
public void setLocalFileMapping(Map>> localFileMapping) {
this.localFileMapping = localFileMapping;
}
public Map>> getLocalFileMapping() {
return localFileMapping;
}
public SnapshotStat getSnapshotStat() {
return snapshotStat;
}
public PageBatchFlusher getDfsPageBatchFlusher() {
return dfsPageBatchFlusher;
}
public void releaseResource() {
regionSnapshotMetas.clear();
if (fileMapping != null) {
fileMapping.clear();
}
if (localFileMapping != null) {
localFileMapping.clear();
}
}
public DBSnapshotResult getDbSnapshotResult() {
return dbSnapshotResult;
}
public void setDbSnapshotResult(DBSnapshotResult dbSnapshotResult) {
this.dbSnapshotResult = dbSnapshotResult;
}
public CompletableFuture getDbSnapshotResultFuture() {
return dbSnapshotResultFuture;
}
public boolean isCanceled() {
return isCanceled;
}
/**
* Should only be called when cancelling this pending snapshot.
*/
@VisibleForTesting
void setCanceled(boolean canceled) {
isCanceled = canceled;
}
}
/**
* Snapshot meta for region.
*/
class GRegionSnapshotMeta {
private GRegionContext gRegionContext;
private PageIndex pageIndex;
private long lastSeqID;
private long removeAllSeqID;
GRegionSnapshotMeta(
GRegionContext gRegionContext,
PageIndex pageIndex,
long lastSeqID,
long removeAllSeqID) {
this.gRegionContext = gRegionContext;
this.pageIndex = pageIndex;
this.lastSeqID = lastSeqID;
this.removeAllSeqID = removeAllSeqID;
}
public GRegionContext getGRegionContext() {
return gRegionContext;
}
public PageIndex getPageIndex() {
return pageIndex;
}
public long getLastSeqID() {
return lastSeqID;
}
public long getRemoveAllSeqID() {
return removeAllSeqID;
}
}
/**
* Completed snapshot information.
*/
class CompletedSnapshot {
private final long checkpointID;
private final String metaFilePath;
private final Set dataFileIDs;
public CompletedSnapshot(
long checkpointID,
String metaFilePath,
Set dataFileIDs) {
this.checkpointID = checkpointID;
this.metaFilePath = metaFilePath;
this.dataFileIDs = dataFileIDs;
}
public long getCheckpointID() {
return checkpointID;
}
public String getMetaFilePath() {
return metaFilePath;
}
public Set getDataFileIDs() {
return dataFileIDs;
}
@Override
public int hashCode() {
return Objects.hash(checkpointID, metaFilePath, dataFileIDs);
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
CompletedSnapshot that = (CompletedSnapshot) o;
return checkpointID == that.checkpointID
&& metaFilePath.equals(that.metaFilePath)
&& dataFileIDs.equals(that.dataFileIDs);
}
}
/**
* Meta for a restored snapshot.
*/
class RestoredSnapshot {
private final long checkpointID;
private final String metaFilePath;
private final Map fileMapping;
public RestoredSnapshot(
long checkpointID,
String metaFilePath,
Map fileMapping) {
this.checkpointID = checkpointID;
this.metaFilePath = metaFilePath;
this.fileMapping = fileMapping;
}
public long getCheckpointID() {
return checkpointID;
}
public String getMetaFilePath() {
return metaFilePath;
}
public Map getFileMapping() {
return fileMapping;
}
}
}