/**
* 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.mapred;
import java.io.*;
import java.util.*;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.net.DNSToSwitchMapping;
import org.apache.hadoop.net.NetworkTopology;
import org.apache.hadoop.net.StaticMapping;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.UnixUserGroupInformation;
import org.apache.hadoop.fs.FileSystem;
/**
* This class creates a single-process Map-Reduce cluster for junit testing.
* One thread is created for each server.
*/
public class MiniMRCluster {
private static final Log LOG = LogFactory.getLog(MiniMRCluster.class);
private Thread jobTrackerThread;
private JobTrackerRunner jobTracker;
private int jobTrackerPort = 0;
private int taskTrackerPort = 0;
private int jobTrackerInfoPort = 0;
private int numTaskTrackers;
private List<TaskTrackerRunner> taskTrackerList = new ArrayList<TaskTrackerRunner>();
private List<Thread> taskTrackerThreadList = new ArrayList<Thread>();
private String namenode;
private UnixUserGroupInformation ugi = null;
/**
* An inner class that runs a job tracker.
*/
class JobTrackerRunner implements Runnable {
private JobTracker tracker = null;
JobConf jc = null;
public JobTrackerRunner(JobConf conf) {
jc = conf;
}
public boolean isUp() {
return (tracker != null);
}
public int getJobTrackerPort() {
return tracker.getTrackerPort();
}
public int getJobTrackerInfoPort() {
return tracker.getInfoPort();
}
/**
* Create the job tracker and run it.
*/
public void run() {
try {
jc = (jc == null) ? createJobConf() : createJobConf(jc);
jc.set("mapred.local.dir","build/test/mapred/local");
jc.setClass("topology.node.switch.mapping.impl",
StaticMapping.class, DNSToSwitchMapping.class);
tracker = JobTracker.startTracker(jc);
tracker.offerService();
} catch (Throwable e) {
LOG.error("Job tracker crashed", e);
}
}
/**
* Shutdown the job tracker and wait for it to finish.
*/
public void shutdown() {
try {
if (tracker != null) {
tracker.stopTracker();
}
} catch (Throwable e) {
LOG.error("Problem shutting down job tracker", e);
}
}
}
/**
* An inner class to run the task tracker.
*/
class TaskTrackerRunner implements Runnable {
volatile TaskTracker tt;
int trackerId;
// the localDirs for this taskTracker
String[] localDirs;
volatile boolean isInitialized = false;
volatile boolean isDead = false;
int numDir;
TaskTrackerRunner(int trackerId, int numDir, String hostname)
throws IOException {
this.trackerId = trackerId;
this.numDir = numDir;
localDirs = new String[numDir];
JobConf conf = createJobConf();
if (hostname != null) {
conf.set("slave.host.name", hostname);
}
conf.set("mapred.task.tracker.http.address", "0.0.0.0:0");
conf.set("mapred.task.tracker.report.address",
"127.0.0.1:" + taskTrackerPort);
File localDirBase =
new File(conf.get("mapred.local.dir")).getAbsoluteFile();
localDirBase.mkdirs();
StringBuffer localPath = new StringBuffer();
for(int i=0; i < numDir; ++i) {
File ttDir = new File(localDirBase,
Integer.toString(trackerId) + "_" + 0);
if (!ttDir.mkdirs()) {
if (!ttDir.isDirectory()) {
throw new IOException("Mkdirs failed to create " + ttDir);
}
}
localDirs[i] = ttDir.toString();
if (i != 0) {
localPath.append(",");
}
localPath.append(localDirs[i]);
}
conf.set("mapred.local.dir", localPath.toString());
LOG.info("mapred.local.dir is " + localPath);
try {
tt = new TaskTracker(conf);
isInitialized = true;
} catch (Throwable e) {
isDead = true;
tt = null;
LOG.error("task tracker " + trackerId + " crashed", e);
}
}
/**
* Create and run the task tracker.
*/
public void run() {
try {
if (tt != null) {
tt.run();
}
} catch (Throwable e) {
isDead = true;
tt = null;
LOG.error("task tracker " + trackerId + " crashed", e);
}
}
/**
* Get the local dir for this TaskTracker.
* This is there so that we do not break
* previous tests.
* @return the absolute pathname
*/
public String getLocalDir() {
return localDirs[0];
}
public String[] getLocalDirs(){
return localDirs;
}
public TaskTracker getTaskTracker() {
return tt;
}
/**
* Shut down the server and wait for it to finish.
*/
public void shutdown() {
if (tt != null) {
try {
tt.shutdown();
} catch (Throwable e) {
LOG.error("task tracker " + trackerId + " could not shut down",
e);
}
}
}
}
/**
* Get the local directory for the Nth task tracker
* @param taskTracker the index of the task tracker to check
* @return the absolute pathname of the local dir
*/
public String getTaskTrackerLocalDir(int taskTracker) {
return ((TaskTrackerRunner)
taskTrackerList.get(taskTracker)).getLocalDir();
}
/**
* Get the number of task trackers in the cluster
*/
public int getNumTaskTrackers() {
return taskTrackerList.size();
}
/**
* Wait until the system is idle.
*/
public void waitUntilIdle() {
for(Iterator itr= taskTrackerList.iterator(); itr.hasNext();) {
TaskTrackerRunner runner = (TaskTrackerRunner) itr.next();
while (!runner.isDead && (!runner.isInitialized || !runner.tt.isIdle())) {
if (!runner.isInitialized) {
LOG.info("Waiting for task tracker to start.");
} else {
LOG.info("Waiting for task tracker " + runner.tt.getName() +
" to be idle.");
}
try {
Thread.sleep(1000);
} catch (InterruptedException ie) {}
}
}
}
/**
* Get the actual rpc port used.
*/
public int getJobTrackerPort() {
return jobTrackerPort;
}
public JobConf createJobConf() {
return createJobConf(new JobConf());
}
public JobConf createJobConf(JobConf conf) {
JobConf result = new JobConf(conf);
FileSystem.setDefaultUri(result, namenode);
result.set("mapred.job.tracker", "localhost:"+jobTrackerPort);
result.set("mapred.job.tracker.http.address",
"127.0.0.1:" + jobTrackerInfoPort);
if (ugi != null) {
result.set("mapred.system.dir", "/mapred/system");
UnixUserGroupInformation.saveToConf(result,
UnixUserGroupInformation.UGI_PROPERTY_NAME, ugi);
}
// for debugging have all task output sent to the test output
JobClient.setTaskOutputFilter(result, JobClient.TaskStatusFilter.ALL);
return result;
}
/**
* Create the config and the cluster.
* @param numTaskTrackers no. of tasktrackers in the cluster
* @param namenode the namenode
* @param numDir no. of directories
* @throws IOException
*/
public MiniMRCluster(int numTaskTrackers, String namenode, int numDir,
String[] racks, String[] hosts) throws IOException {
this(0, 0, numTaskTrackers, namenode, numDir, racks, hosts);
}
/**
* Create the config and the cluster.
* @param numTaskTrackers no. of tasktrackers in the cluster
* @param namenode the namenode
* @param numDir no. of directories
* @param racks Array of racks
* @param hosts Array of hosts in the corresponding racks
* @param conf Default conf for the jobtracker
* @throws IOException
*/
public MiniMRCluster(int numTaskTrackers, String namenode, int numDir,
String[] racks, String[] hosts, JobConf conf)
throws IOException {
this(0, 0, numTaskTrackers, namenode, numDir, racks, hosts, null, conf);
}
/**
* Create the config and the cluster.
* @param numTaskTrackers no. of tasktrackers in the cluster
* @param namenode the namenode
* @param numDir no. of directories
* @throws IOException
*/
public MiniMRCluster(int numTaskTrackers, String namenode, int numDir)
throws IOException {
this(0, 0, numTaskTrackers, namenode, numDir);
}
public MiniMRCluster(int jobTrackerPort,
int taskTrackerPort,
int numTaskTrackers,
String namenode,
int numDir)
throws IOException {
this(jobTrackerPort, taskTrackerPort, numTaskTrackers, namenode,
numDir, null);
}
public MiniMRCluster(int jobTrackerPort,
int taskTrackerPort,
int numTaskTrackers,
String namenode,
int numDir,
String[] racks) throws IOException {
this(jobTrackerPort, taskTrackerPort, numTaskTrackers, namenode,
numDir, racks, null);
}
public MiniMRCluster(int jobTrackerPort,
int taskTrackerPort,
int numTaskTrackers,
String namenode,
int numDir,
String[] racks, String[] hosts) throws IOException {
this(jobTrackerPort, taskTrackerPort, numTaskTrackers, namenode,
numDir, racks, hosts, null);
}
public MiniMRCluster(int jobTrackerPort, int taskTrackerPort,
int numTaskTrackers, String namenode,
int numDir, String[] racks, String[] hosts, UnixUserGroupInformation ugi
) throws IOException {
this(jobTrackerPort, taskTrackerPort, numTaskTrackers, namenode,
numDir, racks, hosts, ugi, null);
}
public MiniMRCluster(int jobTrackerPort, int taskTrackerPort,
int numTaskTrackers, String namenode,
int numDir, String[] racks, String[] hosts, UnixUserGroupInformation ugi,
JobConf conf) throws IOException {
if (racks != null && racks.length < numTaskTrackers) {
LOG.error("Invalid number of racks specified. It should be at least " +
"equal to the number of tasktrackers");
shutdown();
}
if (hosts != null && numTaskTrackers > hosts.length ) {
throw new IllegalArgumentException( "The length of hosts [" + hosts.length
+ "] is less than the number of tasktrackers [" + numTaskTrackers + "].");
}
//Generate rack names if required
if (racks == null) {
System.out.println("Generating rack names for tasktrackers");
racks = new String[numTaskTrackers];
for (int i=0; i < racks.length; ++i) {
racks[i] = NetworkTopology.DEFAULT_RACK;
}
}
//Generate some hostnames if required
if (hosts == null) {
System.out.println("Generating host names for tasktrackers");
hosts = new String[numTaskTrackers];
for (int i = 0; i < numTaskTrackers; i++) {
hosts[i] = "host" + i + ".foo.com";
}
}
this.jobTrackerPort = jobTrackerPort;
this.taskTrackerPort = taskTrackerPort;
this.jobTrackerInfoPort = 0;
this.numTaskTrackers = numTaskTrackers;
this.namenode = namenode;
this.ugi = ugi;
// Create the JobTracker
jobTracker = new JobTrackerRunner(conf);
jobTrackerThread = new Thread(jobTracker);
jobTrackerThread.start();
while (!jobTracker.isUp()) {
try { // let daemons get started
LOG.info("Waiting for JobTracker to start...");
Thread.sleep(1000);
} catch(InterruptedException e) {
}
}
// Set the configuration for the task-trackers
this.jobTrackerPort = jobTracker.getJobTrackerPort();
this.jobTrackerInfoPort = jobTracker.getJobTrackerInfoPort();
// Create the TaskTrackers
for (int idx = 0; idx < numTaskTrackers; idx++) {
if (racks != null) {
StaticMapping.addNodeToRack(hosts[idx],racks[idx]);
}
if (hosts != null) {
NetUtils.addStaticResolution(hosts[idx], "localhost");
}
TaskTrackerRunner taskTracker;
taskTracker = new TaskTrackerRunner(idx, numDir,
hosts == null ? null : hosts[idx]);
Thread taskTrackerThread = new Thread(taskTracker);
taskTrackerList.add(taskTracker);
taskTrackerThreadList.add(taskTrackerThread);
}
// Start the MiniMRCluster
for (Thread taskTrackerThread : taskTrackerThreadList){
taskTrackerThread.start();
}
waitUntilIdle();
}
/**
* Shut down the servers.
*/
public void shutdown() {
try {
waitUntilIdle();
for (int idx = 0; idx < numTaskTrackers; idx++) {
TaskTrackerRunner taskTracker = (TaskTrackerRunner) taskTrackerList.get(idx);
Thread taskTrackerThread = (Thread) taskTrackerThreadList.get(idx);
taskTracker.shutdown();
taskTrackerThread.interrupt();
try {
taskTrackerThread.join();
} catch (InterruptedException ex) {
LOG.error("Problem shutting down task tracker", ex);
}
}
jobTracker.shutdown();
jobTrackerThread.interrupt();
try {
jobTrackerThread.join();
} catch (InterruptedException ex) {
LOG.error("Problem waiting for job tracker to finish", ex);
}
} finally {
File configDir = new File("build", "minimr");
File siteFile = new File(configDir, "hadoop-site.xml");
siteFile.delete();
}
}
public static void main(String[] args) throws IOException {
LOG.info("Bringing up Jobtracker and tasktrackers.");
MiniMRCluster mr = new MiniMRCluster(4, "file:///", 1);
LOG.info("JobTracker and TaskTrackers are up.");
mr.shutdown();
LOG.info("JobTracker and TaskTrackers brought down.");
}
}