| /** |
| * 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.azurebfs.services; |
| |
| import java.net.HttpURLConnection; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Throttles Azure Blob File System 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. |
| */ |
| public final class AbfsClientThrottlingIntercept { |
| private static final Logger LOG = LoggerFactory.getLogger( |
| AbfsClientThrottlingIntercept.class); |
| private static AbfsClientThrottlingIntercept singleton = null; |
| private AbfsClientThrottlingAnalyzer readThrottler = null; |
| private AbfsClientThrottlingAnalyzer writeThrottler = null; |
| private static boolean isAutoThrottlingEnabled = false; |
| |
| // Hide default constructor |
| private AbfsClientThrottlingIntercept() { |
| readThrottler = new AbfsClientThrottlingAnalyzer("read"); |
| writeThrottler = new AbfsClientThrottlingAnalyzer("write"); |
| } |
| |
| public static synchronized void initializeSingleton(boolean enableAutoThrottling) { |
| if (!enableAutoThrottling) { |
| return; |
| } |
| if (singleton == null) { |
| singleton = new AbfsClientThrottlingIntercept(); |
| isAutoThrottlingEnabled = true; |
| LOG.debug("Client-side throttling is enabled for the ABFS file system."); |
| } |
| } |
| |
| static void updateMetrics(AbfsRestOperationType operationType, |
| AbfsHttpOperation abfsHttpOperation) { |
| if (!isAutoThrottlingEnabled || abfsHttpOperation == null) { |
| return; |
| } |
| |
| int status = abfsHttpOperation.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 >= HttpURLConnection.HTTP_INTERNAL_ERROR); |
| |
| switch (operationType) { |
| case Append: |
| contentLength = abfsHttpOperation.getBytesSent(); |
| if (contentLength > 0) { |
| singleton.writeThrottler.addBytesTransferred(contentLength, |
| isFailedOperation); |
| } |
| break; |
| case ReadFile: |
| contentLength = abfsHttpOperation.getBytesReceived(); |
| if (contentLength > 0) { |
| singleton.readThrottler.addBytesTransferred(contentLength, |
| isFailedOperation); |
| } |
| break; |
| default: |
| break; |
| } |
| } |
| |
| /** |
| * Called before the request is sent. Client-side throttling |
| * uses this to suspend the request, if necessary, to minimize errors and |
| * maximize throughput. |
| */ |
| static void sendingRequest(AbfsRestOperationType operationType) { |
| if (!isAutoThrottlingEnabled) { |
| return; |
| } |
| |
| switch (operationType) { |
| case ReadFile: |
| singleton.readThrottler.suspendIfNecessary(); |
| break; |
| case Append: |
| singleton.writeThrottler.suspendIfNecessary(); |
| break; |
| default: |
| break; |
| } |
| } |
| } |