hadoop ClientThrottlingIntercept 源码

haddop ClientThrottlingIntercept 代码

文件路径：/hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azure/ClientThrottlingIntercept.java

/**
 * 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.hadoop.fs.azure;

import com.microsoft.azure.storage.ErrorReceivingResponseEvent;
import com.microsoft.azure.storage.OperationContext;
import com.microsoft.azure.storage.RequestResult;
import com.microsoft.azure.storage.ResponseReceivedEvent;
import com.microsoft.azure.storage.SendingRequestEvent;
import com.microsoft.azure.storage.StorageEvent;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hadoop.classification.InterfaceAudience;

import java.net.HttpURLConnection;

/**
 * Throttles Azure Storage read and write operations to achieve maximum
 * throughput by minimizing errors.  The errors occur when the account ingress
 * or egress limits are exceeded and the server-side throttles requests.
 * Server-side throttling causes the retry policy to be used, but the retry
 * policy sleeps for long periods of time causing the total ingress or egress
 * throughput to be as much as 35% lower than optimal.  The retry policy is also
 * after the fact, in that it applies after a request fails.  On the other hand,
 * the client-side throttling implemented here happens before requests are made
 * and sleeps just enough to minimize errors, allowing optimal ingress and/or
 * egress throughput.
 */
@InterfaceAudience.Private
final class ClientThrottlingIntercept {
  private static final Logger LOG = LoggerFactory.getLogger(
      ClientThrottlingIntercept.class);
  private static ClientThrottlingIntercept singleton = null;
  private ClientThrottlingAnalyzer readThrottler = null;
  private ClientThrottlingAnalyzer writeThrottler = null;

  // Hide default constructor
  private ClientThrottlingIntercept() {
    readThrottler = new ClientThrottlingAnalyzer("read");
    writeThrottler = new ClientThrottlingAnalyzer("write");
    LOG.debug("Client-side throttling is enabled for the WASB file system.");
  }

  static synchronized void initializeSingleton() {
    if (singleton == null) {
      singleton = new ClientThrottlingIntercept();
    }
  }

  static void hook(OperationContext context) {
    context.getErrorReceivingResponseEventHandler().addListener(
        new ErrorReceivingResponseEventHandler());
    context.getSendingRequestEventHandler().addListener(
        new SendingRequestEventHandler());
    context.getResponseReceivedEventHandler().addListener(
        new ResponseReceivedEventHandler());
  }

  private static void updateMetrics(HttpURLConnection conn,
                                    RequestResult result) {
    BlobOperationDescriptor.OperationType operationType
        = BlobOperationDescriptor.getOperationType(conn);
    int status = result.getStatusCode();
    long contentLength = 0;
    // If the socket is terminated prior to receiving a response, the HTTP
    // status may be 0 or -1.  A status less than 200 or greater than or equal
    // to 500 is considered an error.
    boolean isFailedOperation = (status < HttpURLConnection.HTTP_OK
        || status >= java.net.HttpURLConnection.HTTP_INTERNAL_ERROR);

    switch (operationType) {
      case AppendBlock:
      case PutBlock:
      case PutPage:
        contentLength = BlobOperationDescriptor.getContentLengthIfKnown(conn,
            operationType);
        if (contentLength > 0) {
          singleton.writeThrottler.addBytesTransferred(contentLength,
              isFailedOperation);
        }
        break;
      case GetBlob:
        contentLength = BlobOperationDescriptor.getContentLengthIfKnown(conn,
            operationType);
        if (contentLength > 0) {
          singleton.readThrottler.addBytesTransferred(contentLength,
              isFailedOperation);
        }
        break;
      default:
        break;
    }
  }

  /**
   * Called when a network error occurs before the HTTP status and response
   * headers are received. Client-side throttling uses this to collect metrics.
   *
   * @param event The connection, operation, and request state.
   */
  public static void errorReceivingResponse(ErrorReceivingResponseEvent event) {
    updateMetrics((HttpURLConnection) event.getConnectionObject(),
        event.getRequestResult());
  }

  /**
   * Called before the Azure Storage SDK sends a request. Client-side throttling
   * uses this to suspend the request, if necessary, to minimize errors and
   * maximize throughput.
   *
   * @param event The connection, operation, and request state.
   */
  public static void sendingRequest(SendingRequestEvent event) {
    BlobOperationDescriptor.OperationType operationType
        = BlobOperationDescriptor.getOperationType(
            (HttpURLConnection) event.getConnectionObject());
    switch (operationType) {
      case GetBlob:
        singleton.readThrottler.suspendIfNecessary();
        break;
      case AppendBlock:
      case PutBlock:
      case PutPage:
        singleton.writeThrottler.suspendIfNecessary();
        break;
      default:
        break;
    }
  }

  /**
   * Called after the Azure Storage SDK receives a response. Client-side
   * throttling uses this to collect metrics.
   *
   * @param event The connection, operation, and request state.
   */
  public static void responseReceived(ResponseReceivedEvent event) {
    updateMetrics((HttpURLConnection) event.getConnectionObject(),
        event.getRequestResult());
  }

  /**
   * The ErrorReceivingResponseEvent is fired when the Azure Storage SDK
   * encounters a network error before the HTTP status and response headers are
   * received.
   */
  @InterfaceAudience.Private
  static class ErrorReceivingResponseEventHandler
      extends StorageEvent<ErrorReceivingResponseEvent> {

    /**
     * Called when a network error occurs before the HTTP status and response
     * headers are received.  Client-side throttling uses this to collect
     * metrics.
     *
     * @param event The connection, operation, and request state.
     */
    @Override
    public void eventOccurred(ErrorReceivingResponseEvent event) {
      singleton.errorReceivingResponse(event);
    }
  }

  /**
   * The SendingRequestEvent is fired before the Azure Storage SDK sends a
   * request.
   */
  @InterfaceAudience.Private
  static class SendingRequestEventHandler
      extends StorageEvent<SendingRequestEvent> {

    /**
     * Called before the Azure Storage SDK sends a request. Client-side
     * throttling uses this to suspend the request, if necessary, to minimize
     * errors and maximize throughput.
     *
     * @param event The connection, operation, and request state.
     */
    @Override
    public void eventOccurred(SendingRequestEvent event) {
      singleton.sendingRequest(event);
    }
  }

  /**
   * The ResponseReceivedEvent is fired after the Azure Storage SDK receives a
   * response.
   */
  @InterfaceAudience.Private
  static class ResponseReceivedEventHandler
      extends StorageEvent<ResponseReceivedEvent> {

    /**
     * Called after the Azure Storage SDK receives a response. Client-side
     * throttling uses this
     * to collect metrics.
     *
     * @param event The connection, operation, and request state.
     */
    @Override
    public void eventOccurred(ResponseReceivedEvent event) {
      singleton.responseReceived(event);
    }
  }
}

相关信息

hadoop 源码目录

相关文章

hadoop AzureException 源码

hadoop AzureFileSystemThreadPoolExecutor 源码

hadoop AzureFileSystemThreadTask 源码

hadoop AzureLinkedStack 源码

hadoop AzureNativeFileSystemStore 源码

hadoop BlobMaterialization 源码

hadoop BlobOperationDescriptor 源码

hadoop BlockBlobAppendStream 源码

hadoop BlockBlobInputStream 源码

hadoop CachingAuthorizer 源码