StefanRRichter commented on a change in pull request #7674: [FLINK-10043] [State Backends] Refactor RocksDBKeyedStateBackend object construction/initialization/restore code URL: https://github.com/apache/flink/pull/7674#discussion_r258054045
########## File path: flink-state-backends/flink-statebackend-rocksdb/src/main/java/org/apache/flink/contrib/streaming/state/restore/RocksDBIncrementalRestoreOperation.java ########## @@ -0,0 +1,580 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * 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.contrib.streaming.state.restore; + +import org.apache.flink.api.common.typeutils.TypeSerializerSchemaCompatibility; +import org.apache.flink.configuration.ConfigConstants; +import org.apache.flink.contrib.streaming.state.RocksDBIncrementalCheckpointUtils; +import org.apache.flink.contrib.streaming.state.RocksDBKeySerializationUtils; +import org.apache.flink.contrib.streaming.state.RocksDBKeyedStateBackend; +import org.apache.flink.contrib.streaming.state.RocksDBNativeMetricMonitor; +import org.apache.flink.contrib.streaming.state.RocksDBOperationUtils; +import org.apache.flink.contrib.streaming.state.RocksDBStateDownloader; +import org.apache.flink.contrib.streaming.state.RocksDBWriteBatchWrapper; +import org.apache.flink.contrib.streaming.state.RocksIteratorWrapper; +import org.apache.flink.contrib.streaming.state.StateColumnFamilyHandle; +import org.apache.flink.core.fs.CloseableRegistry; +import org.apache.flink.core.fs.FSDataInputStream; +import org.apache.flink.core.fs.FileStatus; +import org.apache.flink.core.fs.FileSystem; +import org.apache.flink.core.fs.Path; +import org.apache.flink.core.memory.DataInputView; +import org.apache.flink.core.memory.DataInputViewStreamWrapper; +import org.apache.flink.runtime.state.BackendBuildingException; +import org.apache.flink.runtime.state.DirectoryStateHandle; +import org.apache.flink.runtime.state.IncrementalKeyedStateHandle; +import org.apache.flink.runtime.state.IncrementalLocalKeyedStateHandle; +import org.apache.flink.runtime.state.KeyGroupRange; +import org.apache.flink.runtime.state.KeyedBackendSerializationProxy; +import org.apache.flink.runtime.state.KeyedStateHandle; +import org.apache.flink.runtime.state.RegisteredStateMetaInfoBase; +import org.apache.flink.runtime.state.StateSerializerProvider; +import org.apache.flink.runtime.state.StreamStateHandle; +import org.apache.flink.runtime.state.metainfo.StateMetaInfoSnapshot; +import org.apache.flink.util.IOUtils; +import org.apache.flink.util.StateMigrationException; + +import org.rocksdb.ColumnFamilyDescriptor; +import org.rocksdb.ColumnFamilyHandle; +import org.rocksdb.ColumnFamilyOptions; +import org.rocksdb.DBOptions; +import org.rocksdb.RocksDB; +import org.rocksdb.RocksDBException; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import javax.annotation.Nonnull; + +import java.io.File; +import java.io.IOException; +import java.nio.file.Files; +import java.nio.file.StandardCopyOption; +import java.util.ArrayList; +import java.util.Collection; +import java.util.List; +import java.util.Map; +import java.util.Objects; +import java.util.UUID; + +import static org.apache.flink.contrib.streaming.state.snapshot.RocksSnapshotUtil.SST_FILE_SUFFIX; + +/** + * Encapsulates the process of restoring a RocksDB instance from an incremental snapshot. + */ +public class RocksDBIncrementalRestoreOperation<K> extends AbstractRocksDBRestoreOperation<K> { + private static final Logger LOG = LoggerFactory.getLogger(RocksDBIncrementalRestoreOperation.class); + + private final String operatorIdentifier; + private boolean isKeySerializerCompatibilityChecked; + + public RocksDBIncrementalRestoreOperation( + String operatorIdentifier, + KeyGroupRange keyGroupRange, + int keyGroupPrefixBytes, + int numberOfTransferringThreads, + CloseableRegistry cancelStreamRegistry, + ClassLoader userCodeClassLoader, + Map<String, StateColumnFamilyHandle> kvStateInformation, + StateSerializerProvider<K> keySerializerProvider, + File instanceBasePath, + File instanceRocksDBPath, + DBOptions dbOptions, + ColumnFamilyOptions columnOptions, + RocksDBNativeMetricMonitor nativeMetricMonitor, + @Nonnull Collection<KeyedStateHandle> restoreStateHandles) { + super(keyGroupRange, + keyGroupPrefixBytes, + numberOfTransferringThreads, + cancelStreamRegistry, + userCodeClassLoader, + kvStateInformation, + keySerializerProvider, + instanceBasePath, + instanceRocksDBPath, + dbOptions, + columnOptions, + nativeMetricMonitor, + restoreStateHandles); + this.operatorIdentifier = operatorIdentifier; + } + + /** + * Root method that branches for different implementations of {@link KeyedStateHandle}. + */ + @Override + public RocksDBRestoreResult restore() throws Exception { + + if (restoreStateHandles == null || restoreStateHandles.isEmpty()) { + return null; + } + + final KeyedStateHandle theFirstStateHandle = restoreStateHandles.iterator().next(); + + boolean isRescaling = (restoreStateHandles.size() > 1 || + !Objects.equals(theFirstStateHandle.getKeyGroupRange(), keyGroupRange)); + + if (isRescaling) { + restoreWithRescaling(restoreStateHandles); + } else { + restoreWithoutRescaling(theFirstStateHandle); + } + return new RocksDBRestoreResult(this.db, lastCompletedCheckpointId, backendUID, + restoredSstFiles, defaultColumnFamilyHandle); + } + + /** + * Recovery from a single remote incremental state without rescaling. + */ + void restoreWithoutRescaling(KeyedStateHandle rawStateHandle) throws Exception { + // 1. Prepare for restore without rescaling + Path temporaryRestoreInstancePath = new Path( + instanceBasePath.getAbsolutePath(), + UUID.randomUUID().toString()); // used as restore source for IncrementalKeyedStateHandle + RocksDBIncrementalRestorePrepareResult prepareResult = + prepareFiles(rawStateHandle, temporaryRestoreInstancePath, cancelStreamRegistry); + Path restoreSourcePath = prepareResult.getLocalKeyedStateHandle().getDirectoryStateHandle().getDirectory(); + if (rawStateHandle instanceof IncrementalKeyedStateHandle) { + backendUID = ((IncrementalKeyedStateHandle) rawStateHandle).getBackendIdentifier(); + } else { + backendUID = ((IncrementalLocalKeyedStateHandle) rawStateHandle).getBackendIdentifier(); + } + LOG.debug("Restoring keyed backend uid in operator {} from incremental snapshot to {}.", + this.operatorIdentifier, this.backendUID); + if (!instanceRocksDBPath.mkdirs()) { + String errMsg = "Could not create RocksDB data directory: " + instanceBasePath.getAbsolutePath(); + LOG.error(errMsg); + throw new IOException(errMsg); + } + try { + restoreInstanceDirectoryFromPath(restoreSourcePath, dbPath); + } finally { + FileSystem restoreFileSystem = restoreSourcePath.getFileSystem(); + if (restoreFileSystem.exists(restoreSourcePath)) { + restoreFileSystem.delete(restoreSourcePath, true); + } + } + // 2. Open db instance + openDB(); + // 3. Use the restore sst files as the base for succeeding checkpoints + IncrementalLocalKeyedStateHandle restoreStateHandle = prepareResult.getLocalKeyedStateHandle(); + restoredSstFiles.put( + restoreStateHandle.getCheckpointId(), + restoreStateHandle.getSharedStateHandleIDs()); + lastCompletedCheckpointId = restoreStateHandle.getCheckpointId(); + // 4. Register column family handles + registerCFHandles(prepareResult.getStateMetaInfoSnapshots()); + } + + private void registerCFHandles(List<StateMetaInfoSnapshot> metaInfoSnapshots) + throws BackendBuildingException { + // Register CF handlers + for (int i = 0; i < metaInfoSnapshots.size(); ++i) { + try { + getOrRegisterColumnFamilyHandle( + kvStateInformation, + nativeMetricMonitor, + db, + columnFamilyDescriptors.get(i), + columnFamilyHandles.get(i), + metaInfoSnapshots.get(i)); + } catch (RocksDBException e) { + String errMsg = "Failed to register CF handle."; + LOG.error(errMsg, e); + throw new BackendBuildingException(errMsg, e); + } + } + } + + private RocksDBIncrementalRestorePrepareResult prepareFiles( + KeyedStateHandle stateHandle, + Path restoreInstancePath, + CloseableRegistry cancelStreamRegistry) throws IOException { + RocksDBIncrementalRestorePrepareResult prepareResult; + try { + prepareResult = prepareFiles( + stateHandle, + restoreInstancePath, + numberOfTransferringThreads, + cancelStreamRegistry, + userCodeClassLoader, + columnOptions + ); + } catch (Exception e) { + // clean up + FileSystem restoreFileSystem = restoreInstancePath.getFileSystem(); + if (restoreFileSystem.exists(restoreInstancePath)) { + restoreFileSystem.delete(restoreInstancePath, true); + } + // log and rethrow + String errMsg = "Failed to prepare files for restore from incremental state handle."; + LOG.error(errMsg, e); + throw new BackendBuildingException(errMsg, e); + } + return prepareResult; + } + + public RocksDBIncrementalRestorePrepareResult prepareFiles( + KeyedStateHandle rawStateHandle, + Path temporaryRestoreInstancePath, + int numberOfTransferingThreads, + CloseableRegistry cancelStreamRegistry, + ClassLoader userCodeClassLoader, + ColumnFamilyOptions columnFamilyOptions) throws Exception { + + IncrementalLocalKeyedStateHandle localKeyedStateHandle; + List<StateMetaInfoSnapshot> stateMetaInfoSnapshots; + KeyedBackendSerializationProxy<K> serializationProxy; + if (rawStateHandle instanceof IncrementalKeyedStateHandle) { + IncrementalKeyedStateHandle restoreStateHandle = (IncrementalKeyedStateHandle) rawStateHandle; + + // read state data. + try (RocksDBStateDownloader rocksDBStateDownloader = + new RocksDBStateDownloader(numberOfTransferingThreads)) { + rocksDBStateDownloader.transferAllStateDataToDirectory( + restoreStateHandle, + temporaryRestoreInstancePath, + cancelStreamRegistry); + } + + serializationProxy = readMetaData(restoreStateHandle.getMetaStateHandle(), cancelStreamRegistry, userCodeClassLoader); + stateMetaInfoSnapshots = serializationProxy.getStateMetaInfoSnapshots(); + columnFamilyDescriptors = createAndRegisterColumnFamilyDescriptors(stateMetaInfoSnapshots, columnFamilyOptions); + + // since we transferred all remote state to a local directory, we can use the same code as for + // local recovery. + localKeyedStateHandle = new IncrementalLocalKeyedStateHandle( + restoreStateHandle.getBackendIdentifier(), + restoreStateHandle.getCheckpointId(), + new DirectoryStateHandle(temporaryRestoreInstancePath), + restoreStateHandle.getKeyGroupRange(), + restoreStateHandle.getMetaStateHandle(), + restoreStateHandle.getSharedState().keySet()); + } else if (rawStateHandle instanceof IncrementalLocalKeyedStateHandle) { + // Recovery from local incremental state. + localKeyedStateHandle = (IncrementalLocalKeyedStateHandle) rawStateHandle; + serializationProxy = readMetaData(localKeyedStateHandle.getMetaDataState(), cancelStreamRegistry, userCodeClassLoader); + stateMetaInfoSnapshots = serializationProxy.getStateMetaInfoSnapshots(); + columnFamilyDescriptors = createAndRegisterColumnFamilyDescriptors(stateMetaInfoSnapshots, columnFamilyOptions); + } else { + throw new IllegalStateException("Unexpected state handle type, " + + "expected " + IncrementalKeyedStateHandle.class + " or " + IncrementalLocalKeyedStateHandle.class + + ", but found " + rawStateHandle.getClass()); + } + columnFamilyHandles = new ArrayList<>(columnFamilyDescriptors.size() + 1); + return new RocksDBIncrementalRestorePrepareResult(stateMetaInfoSnapshots, localKeyedStateHandle); + } + + /** + * Recovery from multi incremental states with rescaling. For rescaling, this method creates a temporary + * RocksDB instance for a key-groups shard. All contents from the temporary instance are copied into the + * real restore instance and then the temporary instance is discarded. + */ + void restoreWithRescaling(Collection<KeyedStateHandle> restoreStateHandles) throws Exception { + // Init DB instance + initDBWithRescaling(restoreStateHandles); + // Do restore + byte[] startKeyGroupPrefixBytes = new byte[keyGroupPrefixBytes]; + RocksDBKeySerializationUtils.serializeKeyGroup(keyGroupRange.getStartKeyGroup(), startKeyGroupPrefixBytes); + + byte[] stopKeyGroupPrefixBytes = new byte[keyGroupPrefixBytes]; + RocksDBKeySerializationUtils.serializeKeyGroup(keyGroupRange.getEndKeyGroup() + 1, stopKeyGroupPrefixBytes); + + for (KeyedStateHandle rawStateHandle : restoreStateHandles) { + + if (!(rawStateHandle instanceof IncrementalKeyedStateHandle)) { + throw new IllegalStateException("Unexpected state handle type, " + + "expected " + IncrementalKeyedStateHandle.class + + ", but found " + rawStateHandle.getClass()); + } + + Path temporaryRestoreInstancePath = new Path(instanceBasePath.getAbsolutePath() + UUID.randomUUID().toString()); + try (RestoredDBInstance tmpRestoreDBInfo = restoreDBInstanceFromStateHandle( + (IncrementalKeyedStateHandle) rawStateHandle, + temporaryRestoreInstancePath); + RocksDBWriteBatchWrapper writeBatchWrapper = new RocksDBWriteBatchWrapper(this.db)) { + + List<ColumnFamilyDescriptor> tmpColumnFamilyDescriptors = tmpRestoreDBInfo.columnFamilyDescriptors; + List<ColumnFamilyHandle> tmpColumnFamilyHandles = tmpRestoreDBInfo.columnFamilyHandles; + + // iterating only the requested descriptors automatically skips the default column family handle + for (int i = 0; i < tmpColumnFamilyDescriptors.size(); ++i) { + ColumnFamilyHandle tmpColumnFamilyHandle = tmpColumnFamilyHandles.get(i); + ColumnFamilyDescriptor tmpColumnFamilyDescriptor = tmpColumnFamilyDescriptors.get(i); + + ColumnFamilyHandle targetColumnFamilyHandle = getOrRegisterColumnFamilyHandle( + kvStateInformation, nativeMetricMonitor, this.db, + tmpColumnFamilyDescriptor, null, tmpRestoreDBInfo.stateMetaInfoSnapshots.get(i)); + + try (RocksIteratorWrapper iterator = RocksDBKeyedStateBackend.getRocksIterator(tmpRestoreDBInfo.db, tmpColumnFamilyHandle)) { + + iterator.seek(startKeyGroupPrefixBytes); + + while (iterator.isValid()) { + + if (RocksDBIncrementalCheckpointUtils.beforeThePrefixBytes(iterator.key(), stopKeyGroupPrefixBytes)) { + writeBatchWrapper.put(targetColumnFamilyHandle, iterator.key(), iterator.value()); + } else { + // Since the iterator will visit the record according to the sorted order, + // we can just break here. + break; + } + + iterator.next(); + } + } // releases native iterator resources + } + } finally { + FileSystem restoreFileSystem = temporaryRestoreInstancePath.getFileSystem(); + if (restoreFileSystem.exists(temporaryRestoreInstancePath)) { + restoreFileSystem.delete(temporaryRestoreInstancePath, true); + } + } + } + } + + private void initDBWithRescaling(Collection<KeyedStateHandle> restoreStateHandles) throws IOException { + // Prepare for restore with rescaling + IncrementalKeyedStateHandle initialHandle = + (IncrementalKeyedStateHandle) RocksDBIncrementalCheckpointUtils.chooseTheBestStateHandleForInitial( + restoreStateHandles, keyGroupRange); + Path instancePath = new Path(dbPath); + if (initialHandle != null) { + restoreStateHandles.remove(initialHandle); + // 1. Download target files + RocksDBIncrementalRestorePrepareResult prepareResult = + prepareFiles(initialHandle, instancePath, cancelStreamRegistry); + // 2. Open db instance + openDB(); + // 3. Clip the DB instance + try { + RocksDBIncrementalCheckpointUtils.clipDBWithKeyGroupRange( + db, + columnFamilyHandles, + keyGroupRange, + initialHandle.getKeyGroupRange(), + keyGroupPrefixBytes); + } catch (RocksDBException e) { + String errMsg = "Failed to clip DB after initialization."; + LOG.error(errMsg, e); + throw new BackendBuildingException(errMsg, e); + } + // 4. Register column family handles + registerCFHandles(prepareResult.getStateMetaInfoSnapshots()); + } else { + openDB(); + } + } + + /** + * Entity to hold the temporary RocksDB instance created for restore. + */ + private static class RestoredDBInstance implements AutoCloseable { + + @Nonnull + private final RocksDB db; + + @Nonnull + private final ColumnFamilyHandle defaultColumnFamilyHandle; + + @Nonnull + private final List<ColumnFamilyHandle> columnFamilyHandles; + + @Nonnull + private final List<ColumnFamilyDescriptor> columnFamilyDescriptors; + + @Nonnull + private final List<StateMetaInfoSnapshot> stateMetaInfoSnapshots; + + private RestoredDBInstance( + @Nonnull RocksDB db, + @Nonnull List<ColumnFamilyHandle> columnFamilyHandles, + @Nonnull List<ColumnFamilyDescriptor> columnFamilyDescriptors, + @Nonnull List<StateMetaInfoSnapshot> stateMetaInfoSnapshots) { + this.db = db; + this.defaultColumnFamilyHandle = columnFamilyHandles.remove(0); + this.columnFamilyHandles = columnFamilyHandles; + this.columnFamilyDescriptors = columnFamilyDescriptors; + this.stateMetaInfoSnapshots = stateMetaInfoSnapshots; + } + + @Override + public void close() { + + IOUtils.closeQuietly(defaultColumnFamilyHandle); + + for (ColumnFamilyHandle columnFamilyHandle : columnFamilyHandles) { + IOUtils.closeQuietly(columnFamilyHandle); Review comment: Could use `closeAllQuietly` instead of loop ---------------------------------------------------------------- This is an automated message from the Apache Git Service. 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