[120] | 1 | /** |
---|
| 2 | * Licensed to the Apache Software Foundation (ASF) under one |
---|
| 3 | * or more contributor license agreements. See the NOTICE file |
---|
| 4 | * distributed with this work for additional information |
---|
| 5 | * regarding copyright ownership. The ASF licenses this file |
---|
| 6 | * to you under the Apache License, Version 2.0 (the |
---|
| 7 | * "License"); you may not use this file except in compliance |
---|
| 8 | * with the License. You may obtain a copy of the License at |
---|
| 9 | * |
---|
| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
---|
| 11 | * |
---|
| 12 | * Unless required by applicable law or agreed to in writing, software |
---|
| 13 | * distributed under the License is distributed on an "AS IS" BASIS, |
---|
| 14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
---|
| 15 | * See the License for the specific language governing permissions and |
---|
| 16 | * limitations under the License. |
---|
| 17 | */ |
---|
| 18 | package org.apache.hadoop.hdfs; |
---|
| 19 | |
---|
| 20 | import java.io.IOException; |
---|
| 21 | import java.io.InputStream; |
---|
| 22 | import java.io.OutputStream; |
---|
| 23 | |
---|
| 24 | import org.apache.commons.logging.Log; |
---|
| 25 | import org.apache.commons.logging.LogFactory; |
---|
| 26 | import org.apache.hadoop.conf.Configuration; |
---|
| 27 | import org.apache.hadoop.fs.*; |
---|
| 28 | import org.apache.hadoop.fs.permission.FsPermission; |
---|
| 29 | import org.apache.hadoop.hdfs.protocol.*; |
---|
| 30 | import org.apache.hadoop.hdfs.protocol.FSConstants.UpgradeAction; |
---|
| 31 | import org.apache.hadoop.hdfs.server.common.*; |
---|
| 32 | import org.apache.hadoop.hdfs.server.namenode.NotReplicatedYetException; |
---|
| 33 | import org.apache.hadoop.io.*; |
---|
| 34 | import org.apache.hadoop.ipc.RemoteException; |
---|
| 35 | import org.apache.hadoop.security.AccessControlException; |
---|
| 36 | |
---|
| 37 | import junit.framework.TestCase; |
---|
| 38 | |
---|
| 39 | |
---|
| 40 | /** |
---|
| 41 | * These tests make sure that DFSClient retries fetching data from DFS |
---|
| 42 | * properly in case of errors. |
---|
| 43 | */ |
---|
| 44 | public class TestDFSClientRetries extends TestCase { |
---|
| 45 | public static final Log LOG = |
---|
| 46 | LogFactory.getLog(TestDFSClientRetries.class.getName()); |
---|
| 47 | |
---|
| 48 | // writes 'len' bytes of data to out. |
---|
| 49 | private static void writeData(OutputStream out, int len) throws IOException { |
---|
| 50 | byte [] buf = new byte[4096*16]; |
---|
| 51 | while(len > 0) { |
---|
| 52 | int toWrite = Math.min(len, buf.length); |
---|
| 53 | out.write(buf, 0, toWrite); |
---|
| 54 | len -= toWrite; |
---|
| 55 | } |
---|
| 56 | } |
---|
| 57 | |
---|
| 58 | /** |
---|
| 59 | * This makes sure that when DN closes clients socket after client had |
---|
| 60 | * successfully connected earlier, the data can still be fetched. |
---|
| 61 | */ |
---|
| 62 | public void testWriteTimeoutAtDataNode() throws IOException, |
---|
| 63 | InterruptedException { |
---|
| 64 | Configuration conf = new Configuration(); |
---|
| 65 | |
---|
| 66 | final int writeTimeout = 100; //milliseconds. |
---|
| 67 | // set a very short write timeout for datanode, so that tests runs fast. |
---|
| 68 | conf.setInt("dfs.datanode.socket.write.timeout", writeTimeout); |
---|
| 69 | // set a smaller block size |
---|
| 70 | final int blockSize = 10*1024*1024; |
---|
| 71 | conf.setInt("dfs.block.size", blockSize); |
---|
| 72 | conf.setInt("dfs.client.max.block.acquire.failures", 1); |
---|
| 73 | // set a small buffer size |
---|
| 74 | final int bufferSize = 4096; |
---|
| 75 | conf.setInt("io.file.buffer.size", bufferSize); |
---|
| 76 | |
---|
| 77 | MiniDFSCluster cluster = new MiniDFSCluster(conf, 3, true, null); |
---|
| 78 | |
---|
| 79 | try { |
---|
| 80 | cluster.waitActive(); |
---|
| 81 | FileSystem fs = cluster.getFileSystem(); |
---|
| 82 | |
---|
| 83 | Path filePath = new Path("/testWriteTimeoutAtDataNode"); |
---|
| 84 | OutputStream out = fs.create(filePath, true, bufferSize); |
---|
| 85 | |
---|
| 86 | // write a 2 block file. |
---|
| 87 | writeData(out, 2*blockSize); |
---|
| 88 | out.close(); |
---|
| 89 | |
---|
| 90 | byte[] buf = new byte[1024*1024]; // enough to empty TCP buffers. |
---|
| 91 | |
---|
| 92 | InputStream in = fs.open(filePath, bufferSize); |
---|
| 93 | |
---|
| 94 | //first read a few bytes |
---|
| 95 | IOUtils.readFully(in, buf, 0, bufferSize/2); |
---|
| 96 | //now read few more chunks of data by sleeping in between : |
---|
| 97 | for(int i=0; i<10; i++) { |
---|
| 98 | Thread.sleep(2*writeTimeout); // force write timeout at the datanode. |
---|
| 99 | // read enough to empty out socket buffers. |
---|
| 100 | IOUtils.readFully(in, buf, 0, buf.length); |
---|
| 101 | } |
---|
| 102 | // successfully read with write timeout on datanodes. |
---|
| 103 | in.close(); |
---|
| 104 | } finally { |
---|
| 105 | cluster.shutdown(); |
---|
| 106 | } |
---|
| 107 | } |
---|
| 108 | |
---|
| 109 | // more tests related to different failure cases can be added here. |
---|
| 110 | |
---|
| 111 | class TestNameNode implements ClientProtocol |
---|
| 112 | { |
---|
| 113 | int num_calls = 0; |
---|
| 114 | |
---|
| 115 | // The total number of calls that can be made to addBlock |
---|
| 116 | // before an exception is thrown |
---|
| 117 | int num_calls_allowed; |
---|
| 118 | public final String ADD_BLOCK_EXCEPTION = "Testing exception thrown from" |
---|
| 119 | + "TestDFSClientRetries::" |
---|
| 120 | + "TestNameNode::addBlock"; |
---|
| 121 | public final String RETRY_CONFIG |
---|
| 122 | = "dfs.client.block.write.locateFollowingBlock.retries"; |
---|
| 123 | |
---|
| 124 | public TestNameNode(Configuration conf) throws IOException |
---|
| 125 | { |
---|
| 126 | // +1 because the configuration value is the number of retries and |
---|
| 127 | // the first call is not a retry (e.g., 2 retries == 3 total |
---|
| 128 | // calls allowed) |
---|
| 129 | this.num_calls_allowed = conf.getInt(RETRY_CONFIG, 5) + 1; |
---|
| 130 | } |
---|
| 131 | |
---|
| 132 | public long getProtocolVersion(String protocol, |
---|
| 133 | long clientVersion) |
---|
| 134 | throws IOException |
---|
| 135 | { |
---|
| 136 | return versionID; |
---|
| 137 | } |
---|
| 138 | |
---|
| 139 | public LocatedBlock addBlock(String src, String clientName) |
---|
| 140 | throws IOException |
---|
| 141 | { |
---|
| 142 | num_calls++; |
---|
| 143 | if (num_calls > num_calls_allowed) { |
---|
| 144 | throw new IOException("addBlock called more times than " |
---|
| 145 | + RETRY_CONFIG |
---|
| 146 | + " allows."); |
---|
| 147 | } else { |
---|
| 148 | throw new RemoteException(NotReplicatedYetException.class.getName(), |
---|
| 149 | ADD_BLOCK_EXCEPTION); |
---|
| 150 | } |
---|
| 151 | } |
---|
| 152 | |
---|
| 153 | |
---|
| 154 | // The following methods are stub methods that are not needed by this mock class |
---|
| 155 | |
---|
| 156 | public LocatedBlocks getBlockLocations(String src, long offset, long length) throws IOException { return null; } |
---|
| 157 | |
---|
| 158 | public void create(String src, FsPermission masked, String clientName, boolean overwrite, short replication, long blockSize) throws IOException {} |
---|
| 159 | |
---|
| 160 | public LocatedBlock append(String src, String clientName) throws IOException { return null; } |
---|
| 161 | |
---|
| 162 | public boolean setReplication(String src, short replication) throws IOException { return false; } |
---|
| 163 | |
---|
| 164 | public void setPermission(String src, FsPermission permission) throws IOException {} |
---|
| 165 | |
---|
| 166 | public void setOwner(String src, String username, String groupname) throws IOException {} |
---|
| 167 | |
---|
| 168 | public void abandonBlock(Block b, String src, String holder) throws IOException {} |
---|
| 169 | |
---|
| 170 | public boolean complete(String src, String clientName) throws IOException { return false; } |
---|
| 171 | |
---|
| 172 | public void reportBadBlocks(LocatedBlock[] blocks) throws IOException {} |
---|
| 173 | |
---|
| 174 | public boolean rename(String src, String dst) throws IOException { return false; } |
---|
| 175 | |
---|
| 176 | public boolean delete(String src) throws IOException { return false; } |
---|
| 177 | |
---|
| 178 | public boolean delete(String src, boolean recursive) throws IOException { return false; } |
---|
| 179 | |
---|
| 180 | public boolean mkdirs(String src, FsPermission masked) throws IOException { return false; } |
---|
| 181 | |
---|
| 182 | public FileStatus[] getListing(String src) throws IOException { return null; } |
---|
| 183 | |
---|
| 184 | public void renewLease(String clientName) throws IOException {} |
---|
| 185 | |
---|
| 186 | public long[] getStats() throws IOException { return null; } |
---|
| 187 | |
---|
| 188 | public DatanodeInfo[] getDatanodeReport(FSConstants.DatanodeReportType type) throws IOException { return null; } |
---|
| 189 | |
---|
| 190 | public long getPreferredBlockSize(String filename) throws IOException { return 0; } |
---|
| 191 | |
---|
| 192 | public boolean setSafeMode(FSConstants.SafeModeAction action) throws IOException { return false; } |
---|
| 193 | |
---|
| 194 | public void saveNamespace() throws IOException {} |
---|
| 195 | |
---|
| 196 | public boolean restoreFailedStorage(String arg) throws AccessControlException { return false; } |
---|
| 197 | |
---|
| 198 | public void refreshNodes() throws IOException {} |
---|
| 199 | |
---|
| 200 | public void finalizeUpgrade() throws IOException {} |
---|
| 201 | |
---|
| 202 | public UpgradeStatusReport distributedUpgradeProgress(UpgradeAction action) throws IOException { return null; } |
---|
| 203 | |
---|
| 204 | public void metaSave(String filename) throws IOException {} |
---|
| 205 | |
---|
| 206 | public FileStatus getFileInfo(String src) throws IOException { return null; } |
---|
| 207 | |
---|
| 208 | public ContentSummary getContentSummary(String path) throws IOException { return null; } |
---|
| 209 | |
---|
| 210 | public void setQuota(String path, long namespaceQuota, long diskspaceQuota) throws IOException {} |
---|
| 211 | |
---|
| 212 | public void fsync(String src, String client) throws IOException {} |
---|
| 213 | |
---|
| 214 | public void setTimes(String src, long mtime, long atime) throws IOException {} |
---|
| 215 | |
---|
| 216 | } |
---|
| 217 | |
---|
| 218 | public void testNotYetReplicatedErrors() throws IOException |
---|
| 219 | { |
---|
| 220 | Configuration conf = new Configuration(); |
---|
| 221 | |
---|
| 222 | // allow 1 retry (2 total calls) |
---|
| 223 | conf.setInt("dfs.client.block.write.locateFollowingBlock.retries", 1); |
---|
| 224 | |
---|
| 225 | TestNameNode tnn = new TestNameNode(conf); |
---|
| 226 | final DFSClient client = new DFSClient(null, tnn, conf, null); |
---|
| 227 | OutputStream os = client.create("testfile", true); |
---|
| 228 | os.write(20); // write one random byte |
---|
| 229 | |
---|
| 230 | try { |
---|
| 231 | os.close(); |
---|
| 232 | } catch (Exception e) { |
---|
| 233 | assertTrue("Retries are not being stopped correctly", |
---|
| 234 | e.getMessage().equals(tnn.ADD_BLOCK_EXCEPTION)); |
---|
| 235 | } |
---|
| 236 | } |
---|
| 237 | |
---|
| 238 | } |
---|