Victsm commented on a change in pull request #29855: URL: https://github.com/apache/spark/pull/29855#discussion_r502935778
########## File path: common/network-shuffle/src/main/java/org/apache/spark/network/shuffle/OneForOneBlockPusher.java ########## @@ -0,0 +1,126 @@ +/* + * 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.util.Arrays; +import java.util.Map; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import org.apache.spark.network.buffer.ManagedBuffer; +import org.apache.spark.network.buffer.NioManagedBuffer; +import org.apache.spark.network.client.RpcResponseCallback; +import org.apache.spark.network.client.TransportClient; +import org.apache.spark.network.shuffle.protocol.PushBlockStream; + +/** + * Similar to {@link OneForOneBlockFetcher}, but for pushing blocks to remote shuffle service to + * be merged instead of for fetching them from remote shuffle services. This is used by + * ShuffleWriter when the block push process is initiated. The supplied BlockFetchingListener + * is used to handle the success or failure in pushing each blocks. + */ +public class OneForOneBlockPusher { + private static final Logger logger = LoggerFactory.getLogger(OneForOneBlockPusher.class); + private static final ErrorHandler PUSH_ERROR_HANDLER = new ErrorHandler.BlockPushErrorHandler(); + + private final TransportClient client; + private final String appId; + private final String[] blockIds; + private final BlockFetchingListener listener; + private final Map<String, ManagedBuffer> buffers; + + public OneForOneBlockPusher( + TransportClient client, + String appId, + String[] blockIds, + BlockFetchingListener listener, + Map<String, ManagedBuffer> buffers) { + this.client = client; + this.appId = appId; + this.blockIds = blockIds; + this.listener = listener; + this.buffers = buffers; + } + + private class BlockPushCallback implements RpcResponseCallback { + + private int index; + private String blockId; + + BlockPushCallback(int index, String blockId) { + this.index = index; + this.blockId = blockId; + } + + @Override + public void onSuccess(ByteBuffer response) { + // On receipt of a successful block push + listener.onBlockFetchSuccess(blockId, new NioManagedBuffer(ByteBuffer.allocate(0))); + } + + @Override + public void onFailure(Throwable e) { + // Since block push is best effort, i.e., if we encountered a block push failure that's not + // retriable or exceeding the max retires, we should not fail all remaining block pushes. + // The best effort nature makes block push tolerable of a partial completion. Thus, we only + // fail the block that's actually failed. Not that, on the RetryingBlockFetcher side, once + // retry is initiated, it would still invalidate the previous active retry listener, and + // retry all outstanding blocks. We are preventing forwarding unnecessary block push failures + // to the parent listener of the retry listener. The only exceptions would be if the block + // push failure is due to block arriving on the server side after merge finalization, or the + // client fails to establish connection to the server side. In both cases, we would fail all + // remaining blocks. + if (PUSH_ERROR_HANDLER.shouldRetryError(e)) { + String[] targetBlockId = Arrays.copyOfRange(blockIds, index, index + 1); + failRemainingBlocks(targetBlockId, e); + } else { + String[] targetBlockId = Arrays.copyOfRange(blockIds, index, blockIds.length); Review comment: The listener in `failRemainingBlocks` is the `RetryingBlockFetchListener`. Here, if the exception is something that will happen for every block push, i.e., blocking being too late or we have a client side connection issue, all remaining blocks will fail. By eagerly failing all remaining blocks, it could potentially speed up processing on the client side. This is similar to how `OneForOneBlockFetcher` handles things. The difference is that `OneForOneBlockFetcher` always eagerly fail all remaining blocks, while `OneForOneBlockPusher` does not. ---------------------------------------------------------------- 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]
