/**
* 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.hdfs.server.namenode;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.CreateFlag;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.fs.permission.PermissionStatus;
import org.apache.hadoop.hdfs.DFSConfigKeys;
import org.apache.hadoop.hdfs.DFSUtil;
import org.apache.hadoop.hdfs.HdfsConfiguration;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
import org.apache.hadoop.hdfs.protocol.LocatedBlock;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicy;
import org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyRackFaultTolerant;
import org.apache.hadoop.hdfs.server.protocol.NamenodeProtocols;
import org.apache.hadoop.net.StaticMapping;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import java.io.IOException;
import java.util.*;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
public class TestBlockPlacementPolicyRackFaultTolerant {
private static final int DEFAULT_BLOCK_SIZE = 1024;
private MiniDFSCluster cluster = null;
private NamenodeProtocols nameNodeRpc = null;
private FSNamesystem namesystem = null;
private PermissionStatus perm = null;
@Before
public void setup() throws IOException {
StaticMapping.resetMap();
Configuration conf = new HdfsConfiguration();
final ArrayList<String> rackList = new ArrayList<String>();
final ArrayList<String> hostList = new ArrayList<String>();
for (int i = 0; i < 10; i++) {
for (int j = 0; j < 2; j++) {
rackList.add("/rack" + i);
hostList.add("/host" + i + j);
}
}
conf.setClass(DFSConfigKeys.DFS_BLOCK_REPLICATOR_CLASSNAME_KEY,
BlockPlacementPolicyRackFaultTolerant.class,
BlockPlacementPolicy.class);
conf.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, DEFAULT_BLOCK_SIZE);
conf.setInt(DFSConfigKeys.DFS_BYTES_PER_CHECKSUM_KEY, DEFAULT_BLOCK_SIZE / 2);
cluster = new MiniDFSCluster.Builder(conf)
.numDataNodes(hostList.size())
.racks(rackList.toArray(new String[rackList.size()]))
.hosts(hostList.toArray(new String[hostList.size()]))
.build();
cluster.waitActive();
nameNodeRpc = cluster.getNameNodeRpc();
namesystem = cluster.getNamesystem();
perm = new PermissionStatus("TestBlockPlacementPolicyEC", null,
FsPermission.getDefault());
}
@After
public void teardown() {
if (cluster != null) {
cluster.shutdown();
}
}
@Test
public void testChooseTarget() throws Exception {
doTestChooseTargetNormalCase();
doTestChooseTargetSpecialCase();
}
private void doTestChooseTargetNormalCase() throws Exception {
String clientMachine = "client.foo.com";
short[][] testSuite = {
{3, 2}, {3, 7}, {3, 8}, {3, 10}, {9, 1}, {10, 1}, {10, 6}, {11, 6},
{11, 9}
};
// Test 5 files
int fileCount = 0;
for (int i = 0; i < 5; i++) {
for (short[] testCase : testSuite) {
short replication = testCase[0];
short additionalReplication = testCase[1];
String src = "/testfile" + (fileCount++);
// Create the file with client machine
HdfsFileStatus fileStatus = namesystem.startFile(src, perm,
clientMachine, clientMachine, EnumSet.of(CreateFlag.CREATE), true,
replication, DEFAULT_BLOCK_SIZE, null, false);
//test chooseTarget for new file
LocatedBlock locatedBlock = nameNodeRpc.addBlock(src, clientMachine,
null, null, fileStatus.getFileId(), null);
doTestLocatedBlock(replication, locatedBlock);
//test chooseTarget for existing file.
LocatedBlock additionalLocatedBlock =
nameNodeRpc.getAdditionalDatanode(src, fileStatus.getFileId(),
locatedBlock.getBlock(), locatedBlock.getLocations(),
locatedBlock.getStorageIDs(), new DatanodeInfo[0],
additionalReplication, clientMachine);
doTestLocatedBlock(replication + additionalReplication, additionalLocatedBlock);
}
}
}
/**
* Test more randomly. So it covers some special cases.
* Like when some racks already have 2 replicas, while some racks have none,
* we should choose the racks that have none.
*/
private void doTestChooseTargetSpecialCase() throws Exception {
String clientMachine = "client.foo.com";
// Test 5 files
String src = "/testfile_1_";
// Create the file with client machine
HdfsFileStatus fileStatus = namesystem.startFile(src, perm,
clientMachine, clientMachine, EnumSet.of(CreateFlag.CREATE), true,
(short) 20, DEFAULT_BLOCK_SIZE, null, false);
//test chooseTarget for new file
LocatedBlock locatedBlock = nameNodeRpc.addBlock(src, clientMachine,
null, null, fileStatus.getFileId(), null);
doTestLocatedBlock(20, locatedBlock);
DatanodeInfo[] locs = locatedBlock.getLocations();
String[] storageIDs = locatedBlock.getStorageIDs();
for (int time = 0; time < 5; time++) {
shuffle(locs, storageIDs);
for (int i = 1; i < locs.length; i++) {
DatanodeInfo[] partLocs = new DatanodeInfo[i];
String[] partStorageIDs = new String[i];
System.arraycopy(locs, 0, partLocs, 0, i);
System.arraycopy(storageIDs, 0, partStorageIDs, 0, i);
for (int j = 1; j < 20 - i; j++) {
LocatedBlock additionalLocatedBlock =
nameNodeRpc.getAdditionalDatanode(src, fileStatus.getFileId(),
locatedBlock.getBlock(), partLocs,
partStorageIDs, new DatanodeInfo[0],
j, clientMachine);
doTestLocatedBlock(i + j, additionalLocatedBlock);
}
}
}
}
private void shuffle(DatanodeInfo[] locs, String[] storageIDs) {
int length = locs.length;
Object[][] pairs = new Object[length][];
for (int i = 0; i < length; i++) {
pairs[i] = new Object[]{locs[i], storageIDs[i]};
}
DFSUtil.shuffle(pairs);
for (int i = 0; i < length; i++) {
locs[i] = (DatanodeInfo) pairs[i][0];
storageIDs[i] = (String) pairs[i][1];
}
}
private void doTestLocatedBlock(int replication, LocatedBlock locatedBlock) {
assertEquals(replication, locatedBlock.getLocations().length);
HashMap<String, Integer> racksCount = new HashMap<String, Integer>();
for (DatanodeInfo node :
locatedBlock.getLocations()) {
addToRacksCount(node.getNetworkLocation(), racksCount);
}
int minCount = Integer.MAX_VALUE;
int maxCount = Integer.MIN_VALUE;
for (Integer rackCount : racksCount.values()) {
minCount = Math.min(minCount, rackCount);
maxCount = Math.max(maxCount, rackCount);
}
assertTrue(maxCount - minCount <= 1);
}
private void addToRacksCount(String rack, HashMap<String, Integer> racksCount) {
Integer count = racksCount.get(rack);
if (count == null) {
racksCount.put(rack, 1);
} else {
racksCount.put(rack, count + 1);
}
}
}