AHeise commented on a change in pull request #13845: URL: https://github.com/apache/flink/pull/13845#discussion_r587279140
########## File path: flink-streaming-java/src/main/java/org/apache/flink/streaming/runtime/io/recovery/RescalingStreamTaskNetworkInput.java ########## @@ -0,0 +1,280 @@ +/* + * 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.streaming.runtime.io.recovery; + +import org.apache.flink.annotation.Internal; +import org.apache.flink.api.common.TaskInfo; +import org.apache.flink.api.common.typeutils.TypeSerializer; +import org.apache.flink.core.io.InputStatus; +import org.apache.flink.runtime.checkpoint.CheckpointException; +import org.apache.flink.runtime.checkpoint.InflightDataRescalingDescriptor; +import org.apache.flink.runtime.checkpoint.channel.ChannelStateWriter; +import org.apache.flink.runtime.checkpoint.channel.InputChannelInfo; +import org.apache.flink.runtime.event.AbstractEvent; +import org.apache.flink.runtime.io.disk.iomanager.IOManager; +import org.apache.flink.runtime.io.network.api.VirtualChannelSelector; +import org.apache.flink.runtime.io.network.api.serialization.RecordDeserializer; +import org.apache.flink.runtime.io.network.api.serialization.SpillingAdaptiveSpanningRecordDeserializer; +import org.apache.flink.runtime.io.network.partition.consumer.BufferOrEvent; +import org.apache.flink.runtime.plugable.DeserializationDelegate; +import org.apache.flink.streaming.runtime.io.AbstractStreamTaskNetworkInput; +import org.apache.flink.streaming.runtime.io.RecoverableStreamTaskInput; +import org.apache.flink.streaming.runtime.io.StreamTaskInput; +import org.apache.flink.streaming.runtime.io.StreamTaskNetworkInput; +import org.apache.flink.streaming.runtime.io.checkpointing.CheckpointedInputGate; +import org.apache.flink.streaming.runtime.partitioner.ConfigurableStreamPartitioner; +import org.apache.flink.streaming.runtime.partitioner.StreamPartitioner; +import org.apache.flink.streaming.runtime.streamrecord.StreamElement; +import org.apache.flink.streaming.runtime.streamrecord.StreamRecord; +import org.apache.flink.streaming.runtime.streamstatus.StatusWatermarkValve; + +import org.apache.flink.shaded.guava18.com.google.common.collect.Maps; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import java.io.IOException; +import java.util.HashMap; +import java.util.Map; +import java.util.concurrent.CompletableFuture; +import java.util.function.Function; +import java.util.function.Predicate; + +import static org.apache.flink.runtime.checkpoint.CheckpointFailureReason.CHECKPOINT_DECLINED_TASK_NOT_READY; + +/** + * A {@link StreamTaskNetworkInput} implementation that demultiplexes virtual channels. + * + * <p>The demultiplexing works in two dimensions for the following cases. * + * + * <ul> + * <li>Subtasks of the current operator have been collapsed in a round-robin fashion. + * <li>The connected output operator has been rescaled (up and down!) and there is an overlap of + * channels (mostly relevant to keyed exchanges). + * </ul> + * + * <p>In both cases, records from multiple old channels are received over one new physical channel, + * which need to demultiplex the record to correctly restore spanning records (similar to how + * StreamTaskNetworkInput works). + * + * <p>Note that when both cases occur at the same time (downscaling of several operators), there is + * the cross product of channels. So if two subtasks are collapsed and two channels overlap from the + * output side, there is a total of 4 virtual channels. + */ +@Internal +public final class RescalingStreamTaskNetworkInput<T> + extends AbstractStreamTaskNetworkInput<T, DemultiplexingRecordDeserializer<T>> + implements RecoverableStreamTaskInput<T> { + + private static final Logger LOG = + LoggerFactory.getLogger(RescalingStreamTaskNetworkInput.class); + private final IOManager ioManager; + + private RescalingStreamTaskNetworkInput( + CheckpointedInputGate checkpointedInputGate, + TypeSerializer<T> inputSerializer, + IOManager ioManager, + StatusWatermarkValve statusWatermarkValve, + int inputIndex, + InflightDataRescalingDescriptor inflightDataRescalingDescriptor, + Function<Integer, StreamPartitioner<?>> gatePartitioners, + TaskInfo taskInfo) { + super( + checkpointedInputGate, + inputSerializer, + statusWatermarkValve, + inputIndex, + getRecordDeserializers( + checkpointedInputGate, + inputSerializer, + ioManager, + inflightDataRescalingDescriptor, + gatePartitioners, + taskInfo)); + this.ioManager = ioManager; + + LOG.info( + "Created demultiplexer for input {} from {}", + inputIndex, + inflightDataRescalingDescriptor); + } + + private static <T> + Map<InputChannelInfo, DemultiplexingRecordDeserializer<T>> getRecordDeserializers( + CheckpointedInputGate checkpointedInputGate, + TypeSerializer<T> inputSerializer, + IOManager ioManager, + InflightDataRescalingDescriptor rescalingDescriptor, + Function<Integer, StreamPartitioner<?>> gatePartitioners, + TaskInfo taskInfo) { + + RecordFilterFactory<T> recordFilterFactory = + new RecordFilterFactory<>( + taskInfo.getIndexOfThisSubtask(), + inputSerializer, + taskInfo.getNumberOfParallelSubtasks(), + gatePartitioners, + taskInfo.getMaxNumberOfParallelSubtasks()); + final DeserializerFactory deserializerFactory = new DeserializerFactory(ioManager); + Map<InputChannelInfo, DemultiplexingRecordDeserializer<T>> deserializers = + Maps.newHashMapWithExpectedSize(checkpointedInputGate.getChannelInfos().size()); + for (InputChannelInfo channelInfo : checkpointedInputGate.getChannelInfos()) { + deserializers.put( + channelInfo, + DemultiplexingRecordDeserializer.create( + channelInfo, + rescalingDescriptor, + deserializerFactory, + recordFilterFactory)); + } + return deserializers; + } + + @Override + public StreamTaskInput<T> finishRecovery() throws IOException { + close(); + return new StreamTaskNetworkInput<>( + checkpointedInputGate, + inputSerializer, + ioManager, + statusWatermarkValve, + inputIndex); + } + + /** + * Factory method for {@link StreamTaskNetworkInput} or {@link RescalingStreamTaskNetworkInput} + * depending on {@link InflightDataRescalingDescriptor}. + */ + public static <T> StreamTaskInput<T> create( + CheckpointedInputGate checkpointedInputGate, + TypeSerializer<T> inputSerializer, + IOManager ioManager, + StatusWatermarkValve statusWatermarkValve, + int inputIndex, + InflightDataRescalingDescriptor rescalingDescriptorinflightDataRescalingDescriptor, + Function<Integer, StreamPartitioner<?>> gatePartitioners, + TaskInfo taskInfo) { + return rescalingDescriptorinflightDataRescalingDescriptor.equals( + InflightDataRescalingDescriptor.NO_RESCALE) + ? new StreamTaskNetworkInput<>( + checkpointedInputGate, + inputSerializer, + ioManager, + statusWatermarkValve, + inputIndex) + : new RescalingStreamTaskNetworkInput<>( + checkpointedInputGate, + inputSerializer, + ioManager, + statusWatermarkValve, + inputIndex, + rescalingDescriptorinflightDataRescalingDescriptor, + gatePartitioners, + taskInfo); + } + + protected DemultiplexingRecordDeserializer<T> getActiveSerializer( + InputChannelInfo channelInfo) { + final DemultiplexingRecordDeserializer<T> deserialier = + recordDeserializers.get(channelInfo); + if (!deserialier.hasMappings()) { + throw new IllegalStateException( + "Channel " + channelInfo + " should not receive data during recovery."); + } + return deserialier; + } + + protected InputStatus processEvent(BufferOrEvent bufferOrEvent) { + // Event received + final AbstractEvent event = bufferOrEvent.getEvent(); + if (event instanceof VirtualChannelSelector) { + getActiveSerializer(bufferOrEvent.getChannelInfo()) + .select((VirtualChannelSelector) event); + return InputStatus.MORE_AVAILABLE; + } + return super.processEvent(bufferOrEvent); + } + + @Override + public CompletableFuture<Void> prepareSnapshot( + ChannelStateWriter channelStateWriter, long checkpointId) throws CheckpointException { + throw new CheckpointException(CHECKPOINT_DECLINED_TASK_NOT_READY); + } + + static class RecordFilterFactory<T> + implements Function<InputChannelInfo, Predicate<StreamRecord<T>>> { + private final Map<Integer, StreamPartitioner<T>> partitionerCache = new HashMap<>(1); + private final Function<Integer, StreamPartitioner<?>> gatePartitioners; + private final TypeSerializer<T> inputSerializer; + private final int numberOfChannels; + private int subtaskIndex; + private int maxParallelism; + + public RecordFilterFactory( + int subtaskIndex, + TypeSerializer<T> inputSerializer, + int numberOfChannels, + Function<Integer, StreamPartitioner<?>> gatePartitioners, + int maxParallelism) { + this.gatePartitioners = gatePartitioners; + this.inputSerializer = inputSerializer; + this.numberOfChannels = numberOfChannels; + this.subtaskIndex = subtaskIndex; + this.maxParallelism = maxParallelism; + } + + @Override + public Predicate<StreamRecord<T>> apply(InputChannelInfo channelInfo) { + return new RecordFilter<>( + partitionerCache.computeIfAbsent( + channelInfo.getGateIdx(), this::createPartitioner), + inputSerializer, + subtaskIndex); + } + + private StreamPartitioner<T> createPartitioner(Integer index) { + StreamPartitioner<T> partitioner = (StreamPartitioner<T>) gatePartitioners.apply(index); + partitioner.setup(numberOfChannels); + if (partitioner instanceof ConfigurableStreamPartitioner) { + ((ConfigurableStreamPartitioner) partitioner).configure(maxParallelism); + } + return partitioner; + } + } + + static class DeserializerFactory + implements Function< + Integer, RecordDeserializer<DeserializationDelegate<StreamElement>>> { + private final IOManager ioManager; + + public DeserializerFactory(IOManager ioManager) { + this.ioManager = ioManager; + } + + @Override + public RecordDeserializer<DeserializationDelegate<StreamElement>> apply( + Integer totalChannels) { + return new SpillingAdaptiveSpanningRecordDeserializer<>( + ioManager.getSpillingDirectoriesPaths(), + SpillingAdaptiveSpanningRecordDeserializer.DEFAULT_THRESHOLD_FOR_SPILLING + / totalChannels, + SpillingAdaptiveSpanningRecordDeserializer.DEFAULT_FILE_BUFFER_SIZE + / totalChannels); + } Review comment: Good catch. I added some minimum (probably up to debate). ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
