| /** |
| * 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); |
| } |
| } |
| } |