| /** |
| * 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 |
| * <p> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p> |
| * 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.cosn; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.concurrent.TimeUnit; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.io.IOUtils; |
| import org.apache.hadoop.io.retry.RetryPolicies; |
| import org.apache.hadoop.io.retry.RetryPolicy; |
| |
| /** |
| * Used by {@link CosNInputStream} as an asynchronous task |
| * submitted to the thread pool. |
| * Each task is responsible for reading a part of a large file. |
| * It is used to pre-read the data from COS to accelerate file reading process. |
| */ |
| public class CosNFileReadTask implements Runnable { |
| private static final Logger LOG = |
| LoggerFactory.getLogger(CosNFileReadTask.class); |
| |
| private final String key; |
| private final NativeFileSystemStore store; |
| private final CosNInputStream.ReadBuffer readBuffer; |
| |
| private RetryPolicy retryPolicy; |
| |
| public CosNFileReadTask( |
| Configuration conf, |
| String key, NativeFileSystemStore store, |
| CosNInputStream.ReadBuffer readBuffer) { |
| this.key = key; |
| this.store = store; |
| this.readBuffer = readBuffer; |
| |
| RetryPolicy defaultPolicy = |
| RetryPolicies.retryUpToMaximumCountWithFixedSleep( |
| conf.getInt( |
| CosNConfigKeys.COSN_MAX_RETRIES_KEY, |
| CosNConfigKeys.DEFAULT_MAX_RETRIES), |
| conf.getLong( |
| CosNConfigKeys.COSN_RETRY_INTERVAL_KEY, |
| CosNConfigKeys.DEFAULT_RETRY_INTERVAL), |
| TimeUnit.SECONDS); |
| Map<Class<? extends Exception>, RetryPolicy> retryPolicyMap = |
| new HashMap<>(); |
| retryPolicyMap.put(IOException.class, defaultPolicy); |
| retryPolicyMap.put( |
| IndexOutOfBoundsException.class, RetryPolicies.TRY_ONCE_THEN_FAIL); |
| retryPolicyMap.put( |
| NullPointerException.class, RetryPolicies.TRY_ONCE_THEN_FAIL); |
| |
| this.retryPolicy = RetryPolicies.retryByException( |
| defaultPolicy, retryPolicyMap); |
| } |
| |
| @Override |
| public void run() { |
| int retries = 0; |
| RetryPolicy.RetryAction retryAction; |
| try { |
| this.readBuffer.lock(); |
| do { |
| try { |
| InputStream inputStream = this.store.retrieveBlock(this.key, |
| this.readBuffer.getStart(), this.readBuffer.getEnd()); |
| IOUtils.readFully(inputStream, this.readBuffer.getBuffer(), 0, |
| readBuffer.getBuffer().length); |
| inputStream.close(); |
| this.readBuffer.setStatus(CosNInputStream.ReadBuffer.SUCCESS); |
| break; |
| } catch (IOException e) { |
| this.readBuffer.setStatus(CosNInputStream.ReadBuffer.ERROR); |
| LOG.warn( |
| "Exception occurs when retrieve the block range start: " |
| + String.valueOf(this.readBuffer.getStart()) + " end: " |
| + this.readBuffer.getEnd()); |
| try { |
| retryAction = this.retryPolicy.shouldRetry( |
| e, retries++, 0, true); |
| if (retryAction.action |
| == RetryPolicy.RetryAction.RetryDecision.RETRY) { |
| Thread.sleep(retryAction.delayMillis); |
| } |
| } catch (Exception e1) { |
| String errMsg = String.format("Exception occurs when retry[%s] " |
| + "to retrieve the block range start: %s, end:%s", |
| this.retryPolicy.toString(), |
| String.valueOf(this.readBuffer.getStart()), |
| String.valueOf(this.readBuffer.getEnd())); |
| LOG.error(errMsg, e1); |
| break; |
| } |
| } |
| } while (retryAction.action == |
| RetryPolicy.RetryAction.RetryDecision.RETRY); |
| this.readBuffer.signalAll(); |
| } finally { |
| this.readBuffer.unLock(); |
| } |
| } |
| } |