Victsm commented on a change in pull request #29855: URL: https://github.com/apache/spark/pull/29855#discussion_r499071938
########## File path: common/network-shuffle/src/main/java/org/apache/spark/network/shuffle/BlockPushException.java ########## @@ -0,0 +1,86 @@ +/* + * 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.spark.network.shuffle; + +import java.nio.ByteBuffer; +import java.nio.charset.StandardCharsets; + +import org.apache.spark.network.shuffle.protocol.BlockTransferMessage; +import org.apache.spark.network.shuffle.protocol.PushBlockStream; + +/** + * A special exception type that would decode the encoded {@link PushBlockStream} from the + * exception String. This complements the encoding logic in + * {@link org.apache.spark.network.server.TransportRequestHandler}. + */ +public class BlockPushException extends RuntimeException { + private PushBlockStream header; + + /** + * String constant used for generating exception messages indicating a block to be merged + * arrives too late on the server side, and also for later checking such exceptions on the + * client side. When we get a block push failure because of the block arrives too late, we + * will not retry pushing the block nor log the exception on the client side. + */ + public static final String TOO_LATE_MESSAGE_SUFFIX = + "received after merged shuffle is finalized"; + + /** + * String constant used for generating exception messages indicating the server couldn't + * append a block after all available attempts due to collision with other blocks belonging + * to the same shuffle partition, and also for later checking such exceptions on the client + * side. When we get a block push failure because of the block couldn't be written due to + * this reason, we will not log the exception on the client side. + */ + public static final String COULD_NOT_FIND_OPPORTUNITY_MSG_PREFIX = + "Couldn't find an opportunity to write block"; + + private BlockPushException(PushBlockStream header, String message) { + super(message); + this.header = header; + } + + public static BlockPushException decodeException(String message) { + // Use ISO_8859_1 encoding instead of UTF_8. UTF_8 will change the byte content + // for bytes larger than 127. This would render incorrect result when encoding + // decoding the index inside the PushBlockStream message. + ByteBuffer rawBuffer = ByteBuffer.wrap(message.getBytes(StandardCharsets.ISO_8859_1)); + try { + BlockTransferMessage msgObj = BlockTransferMessage.Decoder.fromByteBuffer(rawBuffer); + if (msgObj instanceof PushBlockStream) { + PushBlockStream header = (PushBlockStream) msgObj; + // When decoding the header, the rawBuffer's position is not updated since it was + // consumed via netty's ByteBuf. Updating the rawBuffer's position here to retrieve + // the remaining exception message. + ByteBuffer remainingBuffer = (ByteBuffer) rawBuffer.position(rawBuffer.position() + + header.encodedLength() + 1); + return new BlockPushException(header, + StandardCharsets.UTF_8.decode(remainingBuffer).toString()); + } else { + throw new UnsupportedOperationException(String.format("Cannot decode the header. " + + "Expected PushBlockStream but got %s instead", msgObj.getClass().getSimpleName())); + } + } catch (Exception e) { + return new BlockPushException(null, message); Review comment: Before fixing this, want to first settle the discussion on `TransportRequestHandler` regarding your suggestion to keep `PushBlockStream` as a metadata tracked on the client side. I updated that thread with some of my previous thoughts. ---------------------------------------------------------------- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
