spark-reviews mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From aarondav <...@git.apache.org>
Subject [GitHub] spark pull request: [SPARK-3453] Netty-based BlockTransferService,...
Date Fri, 17 Oct 2014 02:35:51 GMT
Github user aarondav commented on a diff in the pull request:

    https://github.com/apache/spark/pull/2753#discussion_r18999117
  
    --- Diff: network/common/src/main/java/org/apache/spark/network/client/SluiceClient.java
---
    @@ -0,0 +1,161 @@
    +/*
    + * 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.client;
    +
    +import java.io.Closeable;
    +import java.util.UUID;
    +
    +import io.netty.channel.ChannelFuture;
    +import io.netty.channel.ChannelFutureListener;
    +import org.slf4j.Logger;
    +import org.slf4j.LoggerFactory;
    +
    +import org.apache.spark.network.protocol.StreamChunkId;
    +import org.apache.spark.network.protocol.request.ChunkFetchRequest;
    +import org.apache.spark.network.protocol.request.RpcRequest;
    +
    +/**
    + * Client for fetching consecutive chunks of a pre-negotiated stream. This API is intended
to allow
    + * efficient transfer of a large amount of data, broken up into chunks with size ranging
from
    + * hundreds of KB to a few MB.
    + *
    + * Note that while this client deals with the fetching of chunks from a stream (i.e.,
data plane),
    + * the actual setup of the streams is done outside the scope of Sluice. The convenience
method
    + * "sendRPC" is provided to enable control plane communication between the client and
server to
    + * perform this setup.
    + *
    + * For example, a typical workflow might be:
    + * client.sendRPC(new OpenFile("/foo")) --> returns StreamId = 100
    + * client.fetchChunk(streamId = 100, chunkIndex = 0, callback)
    + * client.fetchChunk(streamId = 100, chunkIndex = 1, callback)
    + * ...
    + * client.sendRPC(new CloseStream(100))
    + *
    + * Construct an instance of SluiceClient using {@link SluiceClientFactory}. A single
SluiceClient
    + * may be used for multiple streams, but any given stream must be restricted to a single
client,
    + * in order to avoid out-of-order responses.
    + *
    + * NB: This class is used to make requests to the server, while {@link SluiceClientHandler}
is
    + * responsible for handling responses from the server.
    + *
    + * Concurrency: thread safe and can be called from multiple threads.
    + */
    +public class SluiceClient implements Closeable {
    +  private final Logger logger = LoggerFactory.getLogger(SluiceClient.class);
    +
    +  private final ChannelFuture cf;
    +  private final SluiceClientHandler handler;
    +
    +  private final String serverAddr;
    +
    +  SluiceClient(ChannelFuture cf, SluiceClientHandler handler) {
    +    this.cf = cf;
    +    this.handler = handler;
    +
    +    if (cf != null && cf.channel() != null && cf.channel().remoteAddress()
!= null) {
    +      serverAddr = cf.channel().remoteAddress().toString();
    +    } else {
    +      serverAddr = "<unknown address>";
    +    }
    +  }
    +
    +  public boolean isActive() {
    +    return cf.channel().isActive();
    +  }
    +
    +  /**
    +   * Requests a single chunk from the remote side, from the pre-negotiated streamId.
    +   *
    +   * Chunk indices go from 0 onwards. It is valid to request the same chunk multiple
times, though
    +   * some streams may not support this.
    +   *
    +   * Multiple fetchChunk requests may be outstanding simultaneously, and the chunks are
guaranteed
    +   * to be returned in the same order that they were requested, assuming only a single
SluiceClient
    +   * is used to fetch the chunks.
    +   *
    +   * @param streamId Identifier that refers to a stream in the remote StreamManager.
This should
    +   *                 be agreed upon by client and server beforehand.
    +   * @param chunkIndex 0-based index of the chunk to fetch
    +   * @param callback Callback invoked upon successful receipt of chunk, or upon any failure.
    +   */
    +  public void fetchChunk(
    +      long streamId,
    +      final int chunkIndex,
    +      final ChunkReceivedCallback callback) {
    +    final long startTime = System.currentTimeMillis();
    +    logger.debug("Sending fetch chunk request {} to {}", chunkIndex, serverAddr);
    +
    +    final StreamChunkId streamChunkId = new StreamChunkId(streamId, chunkIndex);
    +    handler.addFetchRequest(streamChunkId, callback);
    +
    +    cf.channel().writeAndFlush(new ChunkFetchRequest(streamChunkId)).addListener(
    +      new ChannelFutureListener() {
    +        @Override
    +        public void operationComplete(ChannelFuture future) throws Exception {
    +          if (future.isSuccess()) {
    +            long timeTaken = System.currentTimeMillis() - startTime;
    +            logger.debug("Sending request {} to {} took {} ms", streamChunkId, serverAddr,
    +                timeTaken);
    +          } else {
    +            // Fail all blocks.
    +            String errorMsg = String.format("Failed to send request %s to %s: %s", streamChunkId,
    +              serverAddr, future.cause().getMessage());
    +            logger.error(errorMsg, future.cause());
    +            future.cause().printStackTrace();
    --- End diff --
    
    whoops!


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastructure@apache.org or file a JIRA ticket
with INFRA.
---

---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscribe@spark.apache.org
For additional commands, e-mail: reviews-help@spark.apache.org


Mime
View raw message