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apache / hadoop-mapreduce / MAPREDUCE-233 / . / src / java / org / apache / hadoop / mapred / JobTracker.java
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/**
* 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.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.Writer;
import java.net.BindException;
import java.net.InetSocketAddress;
import java.net.UnknownHostException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;
import java.util.Vector;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArrayList;
import javax.security.auth.login.LoginException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.LocalFileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.http.HttpServer;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.ipc.RPC;
import org.apache.hadoop.ipc.Server;
import org.apache.hadoop.ipc.RPC.VersionMismatch;
import org.apache.hadoop.mapred.ClusterStatus.BlackListInfo;
import org.apache.hadoop.mapred.JobInProgress.KillInterruptedException;
import org.apache.hadoop.mapred.JobStatusChangeEvent.EventType;
import org.apache.hadoop.mapred.JobTrackerStatistics.TaskTrackerStat;
import org.apache.hadoop.mapred.TaskTrackerStatus.TaskTrackerHealthStatus;
import org.apache.hadoop.mapreduce.ClusterMetrics;
import org.apache.hadoop.mapreduce.QueueInfo;
import org.apache.hadoop.mapreduce.TaskTrackerInfo;
import org.apache.hadoop.mapreduce.TaskType;
import org.apache.hadoop.mapreduce.jobhistory.JobHistory;
import org.apache.hadoop.mapreduce.protocol.ClientProtocol;
import org.apache.hadoop.mapreduce.security.TokenStorage;
import org.apache.hadoop.mapreduce.security.token.JobTokenSecretManager;
import org.apache.hadoop.mapreduce.server.jobtracker.JTConfig;
import org.apache.hadoop.mapreduce.server.jobtracker.TaskTracker;
import org.apache.hadoop.mapreduce.util.ConfigUtil;
import org.apache.hadoop.mapreduce.util.MRAsyncDiskService;
import org.apache.hadoop.net.DNSToSwitchMapping;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.net.NetworkTopology;
import org.apache.hadoop.net.Node;
import org.apache.hadoop.net.NodeBase;
import org.apache.hadoop.net.ScriptBasedMapping;
import org.apache.hadoop.security.AccessControlException;
import org.apache.hadoop.security.PermissionChecker;
import org.apache.hadoop.security.RefreshUserToGroupMappingsProtocol;
import org.apache.hadoop.security.SecurityUtil;
import org.apache.hadoop.security.UnixUserGroupInformation;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.security.authorize.AuthorizationException;
import org.apache.hadoop.security.authorize.ConfiguredPolicy;
import org.apache.hadoop.security.authorize.PolicyProvider;
import org.apache.hadoop.security.authorize.RefreshAuthorizationPolicyProtocol;
import org.apache.hadoop.security.authorize.ServiceAuthorizationManager;
import org.apache.hadoop.util.HostsFileReader;
import org.apache.hadoop.util.ReflectionUtils;
import org.apache.hadoop.util.Service;
import org.apache.hadoop.util.StringUtils;
import org.apache.hadoop.util.VersionInfo;
/*******************************************************
* JobTracker is the central location for submitting and
* tracking MR jobs in a network environment.
*
*******************************************************/
public class JobTracker extends Service
implements MRConstants, InterTrackerProtocol,
ClientProtocol, TaskTrackerManager, RefreshUserToGroupMappingsProtocol,
RefreshAuthorizationPolicyProtocol, AdminOperationsProtocol, JTConfig {
static{
ConfigUtil.loadResources();
}
private long tasktrackerExpiryInterval;
// The interval after which one fault of a tracker will be discarded,
// if there are no faults during this.
private static long UPDATE_FAULTY_TRACKER_INTERVAL = 24 * 60 * 60 * 1000;
// The maximum percentage of trackers in cluster added
// to the 'blacklist' across all the jobs.
private static double MAX_BLACKLIST_PERCENT = 0.50;
// A tracker is blacklisted across jobs only if number of
// blacklists are X% above the average number of blacklists.
// X is the blacklist threshold here.
private double AVERAGE_BLACKLIST_THRESHOLD = 0.50;
// The maximum number of blacklists for a tracker after which the
// tracker could be blacklisted across all jobs
private int MAX_BLACKLISTS_PER_TRACKER = 4;
// Approximate number of heartbeats that could arrive JobTracker
// in a second
private int NUM_HEARTBEATS_IN_SECOND;
private final int DEFAULT_NUM_HEARTBEATS_IN_SECOND = 100;
private final int MIN_NUM_HEARTBEATS_IN_SECOND = 1;
// Scaling factor for heartbeats, used for testing only
private float HEARTBEATS_SCALING_FACTOR;
private final float MIN_HEARTBEATS_SCALING_FACTOR = 0.01f;
private final float DEFAULT_HEARTBEATS_SCALING_FACTOR = 1.0f;
public static enum State { INITIALIZING, RUNNING }
private static final int FS_ACCESS_RETRY_PERIOD = 10000;
static final String JOB_INFO_FILE = "job-info";
private DNSToSwitchMapping dnsToSwitchMapping;
NetworkTopology clusterMap = new NetworkTopology();
private int numTaskCacheLevels; // the max level to which we cache tasks
private Set<Node> nodesAtMaxLevel = new HashSet<Node>();
TaskScheduler taskScheduler;
private final List<JobInProgressListener> jobInProgressListeners =
new CopyOnWriteArrayList<JobInProgressListener>();
// system directory is completely owned by the JobTracker
final static FsPermission SYSTEM_DIR_PERMISSION =
FsPermission.createImmutable((short) 0700); // rwx------
// system files should have 700 permission
final static FsPermission SYSTEM_FILE_PERMISSION =
FsPermission.createImmutable((short) 0700); // rwx------
private static Clock clock = null;
static final Clock DEFAULT_CLOCK = new Clock();
private JobHistory jobHistory;
private final JobTokenSecretManager jobTokenSecretManager
= new JobTokenSecretManager();
JobTokenSecretManager getJobTokenSecretManager() {
return jobTokenSecretManager;
}
private MRAsyncDiskService asyncDiskService;
private String defaultStagingBaseDir;
/**
* A client tried to submit a job before the Job Tracker was ready.
*/
public static class IllegalStateException extends IOException {
private static final long serialVersionUID = 1L;
public IllegalStateException(String msg) {
super(msg);
}
}
private int nextJobId = 1;
public static final Log LOG = LogFactory.getLog(JobTracker.class);
/**
* Returns JobTracker's clock. Note that the correct clock implementation will
* be obtained only when the JobTracker is initialized. If the JobTracker is
* not initialized then the default clock i.e {@link Clock} is returned.
*/
static Clock getClock() {
return clock == null ? DEFAULT_CLOCK : clock;
}
/**
* Return the JT's job history handle.
* @return the jobhistory handle
*/
JobHistory getJobHistory() { return jobHistory; }
/**
* Start the JobTracker with given configuration.
*
* The conf will be modified to reflect the actual ports on which
* the JobTracker is up and running if the user passes the port as
* <code>zero</code>.
*
* @param conf configuration for the JobTracker.
* @throws IOException
*/
public static JobTracker startTracker(JobConf conf)
throws IOException, InterruptedException, LoginException {
return startTracker(conf, DEFAULT_CLOCK);
}
static JobTracker startTracker(JobConf conf, Clock clock)
throws IOException, InterruptedException, LoginException {
return startTracker(conf, clock, generateNewIdentifier());
}
static JobTracker startTracker(JobConf conf, Clock clock, String identifier)
throws IOException, InterruptedException, LoginException {
JobTracker result = null;
while (true) {
try {
result = new JobTracker(conf, clock, identifier);
startService(result);
result.taskScheduler.setTaskTrackerManager(result);
break;
} catch (VersionMismatch e) {
throw e;
} catch (BindException e) {
throw e;
} catch (UnknownHostException e) {
throw e;
} catch (AccessControlException ace) {
// in case of jobtracker not having right access
// bail out
throw ace;
} catch (IOException e) {
LOG.warn("Error starting tracker: " +
e, e);
}
Thread.sleep(1000);
}
if (result != null && result.isRunning()) {
JobEndNotifier.startNotifier();
}
return result;
}
/**
* This stops the tracker, the JobEndNotifier and moves the service into the
* terminated state.
*
* @throws IOException for any trouble during closedown
*/
public synchronized void stopTracker() throws IOException {
close();
}
public long getProtocolVersion(String protocol,
long clientVersion) throws IOException {
if (protocol.equals(InterTrackerProtocol.class.getName())) {
return InterTrackerProtocol.versionID;
} else if (protocol.equals(ClientProtocol.class.getName())){
return ClientProtocol.versionID;
} else if (protocol.equals(RefreshAuthorizationPolicyProtocol.class.getName())){
return RefreshAuthorizationPolicyProtocol.versionID;
} else if (protocol.equals(AdminOperationsProtocol.class.getName())){
return AdminOperationsProtocol.versionID;
} else if (protocol.equals(RefreshUserToGroupMappingsProtocol.class.getName())){
return RefreshUserToGroupMappingsProtocol.versionID;
} else {
throw new IOException("Unknown protocol to job tracker: " + protocol);
}
}
/**
* A thread to timeout tasks that have been assigned to task trackers,
* but that haven't reported back yet.
* Note that I included a stop() method, even though there is no place
* where JobTrackers are cleaned up.
*/
private class ExpireLaunchingTasks implements Runnable {
/**
* This is a map of the tasks that have been assigned to task trackers,
* but that have not yet been seen in a status report.
* map: task-id -> time-assigned
*/
private Map<TaskAttemptID, Long> launchingTasks =
new LinkedHashMap<TaskAttemptID, Long>();
public void run() {
while (true) {
try {
// Every 3 minutes check for any tasks that are overdue
Thread.sleep(tasktrackerExpiryInterval/3);
long now = clock.getTime();
LOG.debug("Starting launching task sweep");
synchronized (JobTracker.this) {
synchronized (launchingTasks) {
Iterator<Map.Entry<TaskAttemptID, Long>> itr =
launchingTasks.entrySet().iterator();
while (itr.hasNext()) {
Map.Entry<TaskAttemptID, Long> pair = itr.next();
TaskAttemptID taskId = pair.getKey();
long age = now - (pair.getValue()).longValue();
LOG.info(taskId + " is " + age + " ms debug.");
if (age > tasktrackerExpiryInterval) {
LOG.info("Launching task " + taskId + " timed out.");
TaskInProgress tip = null;
tip = taskidToTIPMap.get(taskId);
if (tip != null) {
JobInProgress job = tip.getJob();
String trackerName = getAssignedTracker(taskId);
TaskTrackerStatus trackerStatus =
getTaskTrackerStatus(trackerName);
// This might happen when the tasktracker has already
// expired and this thread tries to call failedtask
// again. expire tasktracker should have called failed
// task!
if (trackerStatus != null)
job.failedTask(tip, taskId, "Error launching task",
tip.isMapTask()? TaskStatus.Phase.MAP:
TaskStatus.Phase.STARTING,
TaskStatus.State.FAILED,
trackerName);
}
itr.remove();
} else {
// the tasks are sorted by start time, so once we find
// one that we want to keep, we are done for this cycle.
break;
}
}
}
}
} catch (InterruptedException ie) {
// all done
break;
} catch (Exception e) {
LOG.error("Expire Launching Task Thread got exception: " +
StringUtils.stringifyException(e));
}
}
}
public void addNewTask(TaskAttemptID taskName) {
synchronized (launchingTasks) {
launchingTasks.put(taskName,
clock.getTime());
}
}
public void removeTask(TaskAttemptID taskName) {
synchronized (launchingTasks) {
launchingTasks.remove(taskName);
}
}
}
///////////////////////////////////////////////////////
// Used to expire TaskTrackers that have gone down
///////////////////////////////////////////////////////
class ExpireTrackers implements Runnable {
public ExpireTrackers() {
}
/**
* The run method lives for the life of the JobTracker, and removes TaskTrackers
* that have not checked in for some time.
*/
public void run() {
while (true) {
try {
//
// Thread runs periodically to check whether trackers should be expired.
// The sleep interval must be no more than half the maximum expiry time
// for a task tracker.
//
Thread.sleep(tasktrackerExpiryInterval / 3);
checkExpiredTrackers();
} catch (InterruptedException iex) {
break;
} catch (Exception t) {
LOG.error("Tracker Expiry Thread got exception: " +
StringUtils.stringifyException(t));
}
}
}
}
void checkExpiredTrackers() {
//
// Loop through all expired items in the queue
//
// Need to lock the JobTracker here since we are
// manipulating it's data-structures via
// ExpireTrackers.run -> JobTracker.lostTaskTracker ->
// JobInProgress.failedTask -> JobTracker.markCompleteTaskAttempt
// Also need to lock JobTracker before locking 'taskTracker' &
// 'trackerExpiryQueue' to prevent deadlock:
// @see {@link JobTracker.processHeartbeat(TaskTrackerStatus, boolean)}
synchronized (JobTracker.this) {
synchronized (taskTrackers) {
synchronized (trackerExpiryQueue) {
long now = clock.getTime();
TaskTrackerStatus leastRecent = null;
while ((trackerExpiryQueue.size() > 0) &&
(leastRecent = trackerExpiryQueue.first()) != null &&
((now - leastRecent.getLastSeen()) >
tasktrackerExpiryInterval)) {
// Remove profile from head of queue
trackerExpiryQueue.remove(leastRecent);
String trackerName = leastRecent.getTrackerName();
// Figure out if last-seen time should be updated, or if
// tracker is dead
TaskTracker current = getTaskTracker(trackerName);
TaskTrackerStatus newProfile =
(current == null ) ? null : current.getStatus();
// Items might leave the taskTracker set through other means; the
// status stored in 'taskTrackers' might be null, which means the
// tracker has already been destroyed.
if (newProfile != null) {
if ((now - newProfile.getLastSeen()) >
tasktrackerExpiryInterval) {
// Remove completely after marking the tasks as 'KILLED'
removeTracker(current);
// remove the mapping from the hosts list
String hostname = newProfile.getHost();
hostnameToTaskTracker.get(hostname).remove(trackerName);
} else {
// Update time by inserting latest profile
trackerExpiryQueue.add(newProfile);
}
}
}
}
}
}
}
// Assumes JobTracker, taskTrackers and trackerExpiryQueue are locked on entry
private void removeTracker(TaskTracker tracker) {
lostTaskTracker(tracker);
String trackerName = tracker.getStatus().getTrackerName();
// tracker is lost, and if it is blacklisted, remove
// it from the count of blacklisted trackers in the cluster
if (isBlacklisted(trackerName)) {
faultyTrackers.decrBlackListedTrackers(1);
}
updateTaskTrackerStatus(trackerName, null);
statistics.taskTrackerRemoved(trackerName);
getInstrumentation().decTrackers(1);
}
public synchronized void retireJob(JobID jobid, String historyFile) {
synchronized (jobs) {
JobInProgress job = jobs.get(jobid);
if (job != null) {
JobStatus status = job.getStatus();
//set the historyfile
if (historyFile != null) {
status.setHistoryFile(historyFile);
}
// clean up job files from the local disk
job.cleanupLocalizedJobConf(job.getProfile().getJobID());
//this configuration is primarily for testing
//test cases can set this to false to validate job data structures on
//job completion
boolean retireJob =
conf.getBoolean(JT_RETIREJOBS, true);
if (retireJob) {
//purge the job from memory
removeJobTasks(job);
jobs.remove(job.getProfile().getJobID());
for (JobInProgressListener l : jobInProgressListeners) {
l.jobRemoved(job);
}
String jobUser = job.getProfile().getUser();
LOG.info("Retired job with id: '" +
job.getProfile().getJobID() + "' of user '" +
jobUser + "'");
//add the job status to retired cache
retireJobs.addToCache(job.getStatus());
}
}
}
}
///////////////////////////////////////////////////////
// Used to remove old finished Jobs that have been around for too long
///////////////////////////////////////////////////////
class RetireJobs {
private final Map<JobID, JobStatus> jobIDStatusMap =
new HashMap<JobID, JobStatus>();
private final LinkedList<JobStatus> jobStatusQ =
new LinkedList<JobStatus>();
public RetireJobs() {
}
synchronized void addToCache(JobStatus status) {
status.setRetired();
jobStatusQ.add(status);
jobIDStatusMap.put(status.getJobID(), status);
if (jobStatusQ.size() > retiredJobsCacheSize) {
JobStatus removed = jobStatusQ.remove();
jobIDStatusMap.remove(removed.getJobID());
LOG.info("Retired job removed from cache " + removed.getJobID());
}
}
synchronized JobStatus get(JobID jobId) {
return jobIDStatusMap.get(jobId);
}
@SuppressWarnings("unchecked")
synchronized LinkedList<JobStatus> getAll() {
return (LinkedList<JobStatus>) jobStatusQ.clone();
}
}
enum ReasonForBlackListing {
EXCEEDING_FAILURES,
NODE_UNHEALTHY
}
// The FaultInfo which indicates the number of faults of a tracker
// and when the last fault occurred
// and whether the tracker is blacklisted across all jobs or not
private static class FaultInfo {
static final String FAULT_FORMAT_STRING = "%d failures on the tracker";
int numFaults = 0;
long lastUpdated;
boolean blacklisted;
private boolean isHealthy;
private HashMap<ReasonForBlackListing, String>rfbMap;
FaultInfo(long time) {
numFaults = 0;
lastUpdated = time;
blacklisted = false;
rfbMap = new HashMap<ReasonForBlackListing, String>();
}
void setFaultCount(int num) {
numFaults = num;
}
void setLastUpdated(long timeStamp) {
lastUpdated = timeStamp;
}
int getFaultCount() {
return numFaults;
}
long getLastUpdated() {
return lastUpdated;
}
boolean isBlacklisted() {
return blacklisted;
}
void setBlacklist(ReasonForBlackListing rfb,
String trackerFaultReport) {
blacklisted = true;
this.rfbMap.put(rfb, trackerFaultReport);
}
public void setHealthy(boolean isHealthy) {
this.isHealthy = isHealthy;
}
public boolean isHealthy() {
return isHealthy;
}
public String getTrackerFaultReport() {
StringBuffer sb = new StringBuffer();
for(String reasons : rfbMap.values()) {
sb.append(reasons);
sb.append("\n");
}
if (sb.length() > 0) {
sb.replace(sb.length()-1, sb.length(), "");
}
return sb.toString();
}
Set<ReasonForBlackListing> getReasonforblacklisting() {
return this.rfbMap.keySet();
}
public void unBlacklist() {
this.blacklisted = false;
this.rfbMap.clear();
}
public boolean removeBlackListedReason(ReasonForBlackListing rfb) {
String str = rfbMap.remove(rfb);
return str!=null;
}
public void addBlackListedReason(ReasonForBlackListing rfb, String reason) {
this.rfbMap.put(rfb, reason);
}
}
private class FaultyTrackersInfo {
// A map from hostName to its faults
private Map<String, FaultInfo> potentiallyFaultyTrackers =
new HashMap<String, FaultInfo>();
// This count gives the number of blacklisted trackers in the cluster
// at any time. This is maintained to avoid iteration over
// the potentiallyFaultyTrackers to get blacklisted trackers. And also
// this count doesn't include blacklisted trackers which are lost,
// although the fault info is maintained for lost trackers.
private volatile int numBlacklistedTrackers = 0;
/**
* Increments faults(blacklist by job) for the tracker by one.
*
* Adds the tracker to the potentially faulty list.
* Assumes JobTracker is locked on the entry.
*
* @param hostName
*/
void incrementFaults(String hostName) {
synchronized (potentiallyFaultyTrackers) {
FaultInfo fi = getFaultInfo(hostName, true);
long now = clock.getTime();
int numFaults = fi.getFaultCount();
++numFaults;
fi.setFaultCount(numFaults);
fi.setLastUpdated(now);
if (exceedsFaults(fi)) {
LOG.info("Adding " + hostName + " to the blacklist"
+ " across all jobs");
String reason = String.format(FaultInfo.FAULT_FORMAT_STRING,
numFaults);
blackListTracker(hostName, reason,
ReasonForBlackListing.EXCEEDING_FAILURES);
}
}
}
private void incrBlackListedTrackers(int count) {
numBlacklistedTrackers += count;
getInstrumentation().addBlackListedTrackers(count);
}
private void decrBlackListedTrackers(int count) {
numBlacklistedTrackers -= count;
getInstrumentation().decBlackListedTrackers(count);
}
private void blackListTracker(String hostName, String reason, ReasonForBlackListing rfb) {
FaultInfo fi = getFaultInfo(hostName, true);
boolean blackListed = fi.isBlacklisted();
if(blackListed) {
if (LOG.isDebugEnabled()) {
LOG.debug("Adding blacklisted reason for tracker : " + hostName
+ " Reason for blacklisting is : " + rfb);
}
if (!fi.getReasonforblacklisting().contains(rfb)) {
LOG.info("Adding blacklisted reason for tracker : " + hostName
+ " Reason for blacklisting is : " + rfb);
}
fi.addBlackListedReason(rfb, reason);
} else {
LOG.info("Blacklisting tracker : " + hostName
+ " Reason for blacklisting is : " + rfb);
Set<TaskTracker> trackers =
hostnameToTaskTracker.get(hostName);
synchronized (trackers) {
for (TaskTracker tracker : trackers) {
tracker.cancelAllReservations();
}
}
removeHostCapacity(hostName);
fi.setBlacklist(rfb, reason);
}
}
private boolean canUnBlackListTracker(String hostName,
ReasonForBlackListing rfb) {
FaultInfo fi = getFaultInfo(hostName, false);
if(fi == null) {
return false;
}
Set<ReasonForBlackListing> rfbSet = fi.getReasonforblacklisting();
return fi.isBlacklisted() && rfbSet.contains(rfb);
}
private void unBlackListTracker(String hostName,
ReasonForBlackListing rfb) {
// check if you can black list the tracker then call this methods
FaultInfo fi = getFaultInfo(hostName, false);
if(fi.removeBlackListedReason(rfb)) {
if(fi.getReasonforblacklisting().isEmpty()) {
addHostCapacity(hostName);
LOG.info("Unblacklisting tracker : " + hostName);
fi.unBlacklist();
//We have unBlackListed tracker, so tracker should
//definitely be healthy. Check fault count if fault count
//is zero don't keep it memory.
if(fi.numFaults == 0) {
potentiallyFaultyTrackers.remove(hostName);
}
}
}
}
// Assumes JobTracker is locked on entry.
private FaultInfo getFaultInfo(String hostName,
boolean createIfNeccessary) {
FaultInfo fi = null;
synchronized (potentiallyFaultyTrackers) {
fi = potentiallyFaultyTrackers.get(hostName);
long now = clock.getTime();
if (fi == null && createIfNeccessary) {
fi = new FaultInfo(now);
potentiallyFaultyTrackers.put(hostName, fi);
}
}
return fi;
}
/**
* Blacklists the tracker across all jobs if
* <ol>
* <li>#faults are more than
* MAX_BLACKLISTS_PER_TRACKER (configurable) blacklists</li>
* <li>#faults is 50% (configurable) above the average #faults</li>
* <li>50% the cluster is not blacklisted yet </li>
* </ol>
*/
private boolean exceedsFaults(FaultInfo fi) {
int faultCount = fi.getFaultCount();
if (faultCount >= MAX_BLACKLISTS_PER_TRACKER) {
// calculate avgBlackLists
long clusterSize = getClusterStatus().getTaskTrackers();
long sum = 0;
for (FaultInfo f : potentiallyFaultyTrackers.values()) {
sum += f.getFaultCount();
}
double avg = (double) sum / clusterSize;
long totalCluster = clusterSize + numBlacklistedTrackers;
if ((faultCount - avg) > (AVERAGE_BLACKLIST_THRESHOLD * avg) &&
numBlacklistedTrackers < (totalCluster * MAX_BLACKLIST_PERCENT)) {
return true;
}
}
return false;
}
/**
* Removes the tracker from blacklist and
* from potentially faulty list, when it is restarted.
*
* Assumes JobTracker is locked on the entry.
*
* @param hostName
*/
void markTrackerHealthy(String hostName) {
synchronized (potentiallyFaultyTrackers) {
FaultInfo fi = potentiallyFaultyTrackers.remove(hostName);
if (fi != null && fi.isBlacklisted()) {
LOG.info("Removing " + hostName + " from blacklist");
addHostCapacity(hostName);
}
}
}
/**
* Check whether tasks can be assigned to the tracker.
*
* One fault of the tracker is discarded if there
* are no faults during one day. So, the tracker will get a
* chance again to run tasks of a job.
* Assumes JobTracker is locked on the entry.
*
* @param hostName The tracker name
* @param now The current time
*
* @return true if the tracker is blacklisted
* false otherwise
*/
boolean shouldAssignTasksToTracker(String hostName, long now) {
synchronized (potentiallyFaultyTrackers) {
FaultInfo fi = potentiallyFaultyTrackers.get(hostName);
if (fi != null &&
(now - fi.getLastUpdated()) > UPDATE_FAULTY_TRACKER_INTERVAL) {
int numFaults = fi.getFaultCount() - 1;
fi.setFaultCount(numFaults);
fi.setLastUpdated(now);
if (canUnBlackListTracker(hostName,
ReasonForBlackListing.EXCEEDING_FAILURES)) {
unBlackListTracker(hostName,
ReasonForBlackListing.EXCEEDING_FAILURES);
}
}
return (fi != null && fi.isBlacklisted());
}
}
private void removeHostCapacity(String hostName) {
synchronized (taskTrackers) {
// remove the capacity of trackers on this host
int numTrackersOnHost = 0;
for (TaskTrackerStatus status : getStatusesOnHost(hostName)) {
int mapSlots = status.getMaxMapSlots();
totalMapTaskCapacity -= mapSlots;
int reduceSlots = status.getMaxReduceSlots();
totalReduceTaskCapacity -= reduceSlots;
++numTrackersOnHost;
getInstrumentation().addBlackListedMapSlots(
mapSlots);
getInstrumentation().addBlackListedReduceSlots(
reduceSlots);
}
// remove the host
uniqueHostsMap.remove(hostName);
incrBlackListedTrackers(numTrackersOnHost);
}
}
// This is called on tracker's restart or after a day of blacklist.
private void addHostCapacity(String hostName) {
synchronized (taskTrackers) {
int numTrackersOnHost = 0;
// add the capacity of trackers on the host
for (TaskTrackerStatus status : getStatusesOnHost(hostName)) {
int mapSlots = status.getMaxMapSlots();
totalMapTaskCapacity += mapSlots;
int reduceSlots = status.getMaxReduceSlots();
totalReduceTaskCapacity += reduceSlots;
numTrackersOnHost++;
getInstrumentation().decBlackListedMapSlots(mapSlots);
getInstrumentation().decBlackListedReduceSlots(reduceSlots);
}
uniqueHostsMap.put(hostName,
numTrackersOnHost);
decrBlackListedTrackers(numTrackersOnHost);
}
}
/**
* Whether a host is blacklisted across all the jobs.
*
* Assumes JobTracker is locked on the entry.
* @param hostName
* @return
*/
boolean isBlacklisted(String hostName) {
synchronized (potentiallyFaultyTrackers) {
FaultInfo fi = null;
if ((fi = potentiallyFaultyTrackers.get(hostName)) != null) {
return fi.isBlacklisted();
}
}
return false;
}
// Assumes JobTracker is locked on the entry.
int getFaultCount(String hostName) {
synchronized (potentiallyFaultyTrackers) {
FaultInfo fi = null;
if ((fi = potentiallyFaultyTrackers.get(hostName)) != null) {
return fi.getFaultCount();
}
}
return 0;
}
// Assumes JobTracker is locked on the entry.
Set<ReasonForBlackListing> getReasonForBlackListing(String hostName) {
synchronized (potentiallyFaultyTrackers) {
FaultInfo fi = null;
if ((fi = potentiallyFaultyTrackers.get(hostName)) != null) {
return fi.getReasonforblacklisting();
}
}
return null;
}
// Assumes JobTracker is locked on the entry.
void setNodeHealthStatus(String hostName, boolean isHealthy, String reason) {
FaultInfo fi = null;
// If tracker is not healthy, create a fault info object
// blacklist it.
if (!isHealthy) {
fi = getFaultInfo(hostName, true);
fi.setHealthy(isHealthy);
updateNodeHealthFailureStatistics(hostName, fi);
synchronized (potentiallyFaultyTrackers) {
blackListTracker(hostName, reason,
ReasonForBlackListing.NODE_UNHEALTHY);
}
} else {
fi = getFaultInfo(hostName, false);
if (fi == null) {
return;
} else {
if (canUnBlackListTracker(hostName,
ReasonForBlackListing.NODE_UNHEALTHY)) {
unBlackListTracker(hostName, ReasonForBlackListing.NODE_UNHEALTHY);
}
}
}
}
/**
* Update the node health failure statistics of the given
* host.
*
* We increment the count only when the host transitions
* from healthy -> unhealthy.
*
* @param hostName
* @param fi Fault info object for the host.
*/
private void updateNodeHealthFailureStatistics(String hostName,
FaultInfo fi) {
//Check if the node was already blacklisted due to
//unhealthy reason. If so dont increment the count.
if (!fi.getReasonforblacklisting().contains(
ReasonForBlackListing.NODE_UNHEALTHY)) {
Set<TaskTracker> trackers = hostnameToTaskTracker.get(hostName);
synchronized (trackers) {
for (TaskTracker t : trackers) {
TaskTrackerStat stat = statistics.getTaskTrackerStat(
t.getTrackerName());
stat.incrHealthCheckFailed();
}
}
}
}
}
/**
* Get all task tracker statuses on given host
*
* Assumes JobTracker is locked on the entry
* @param hostName
* @return {@link java.util.List} of {@link TaskTrackerStatus}
*/
private List<TaskTrackerStatus> getStatusesOnHost(String hostName) {
List<TaskTrackerStatus> statuses = new ArrayList<TaskTrackerStatus>();
synchronized (taskTrackers) {
for (TaskTracker tt : taskTrackers.values()) {
TaskTrackerStatus status = tt.getStatus();
if (hostName.equals(status.getHost())) {
statuses.add(status);
}
}
}
return statuses;
}
///////////////////////////////////////////////////////
// Used to recover the jobs upon restart
///////////////////////////////////////////////////////
class RecoveryManager {
private Set<JobID> jobsToRecover; // set of jobs to be recovered
private int recovered;
private int restartCount = 0;
private boolean shouldRecover = false;
public RecoveryManager() {
jobsToRecover = new TreeSet<JobID>();
}
public boolean contains(JobID id) {
return jobsToRecover.contains(id);
}
int getRecovered() {
return recovered;
}
void addJobForRecovery(JobID id) {
jobsToRecover.add(id);
}
public boolean shouldRecover() {
return shouldRecover;
}
Set<JobID> getJobsToRecover() {
return jobsToRecover;
}
// add the job
void addJobForRecovery(FileStatus status) throws IOException {
recoveryManager.addJobForRecovery(JobID.forName(status.getPath().getName()));
shouldRecover = true; // enable actual recovery if num-files > 1
}
Path getRestartCountFile() {
return new Path(getSystemDir(), "jobtracker.info");
}
Path getTempRestartCountFile() {
return new Path(getSystemDir(), "jobtracker.info.recover");
}
/**
* Initialize the recovery process. It simply creates a jobtracker.info file
* in the jobtracker's system directory and writes its restart count in it.
* For the first start, the jobtracker writes '0' in it. Upon subsequent
* restarts the jobtracker replaces the count with its current count which
* is (old count + 1). The whole purpose of this api is to obtain restart
* counts across restarts to avoid attempt-id clashes.
*
* Note that in between if the jobtracker.info files goes missing then the
* jobtracker will disable recovery and continue.
*
*/
void updateRestartCount() throws IOException {
Path restartFile = getRestartCountFile();
Path tmpRestartFile = getTempRestartCountFile();
FileSystem fs = restartFile.getFileSystem(conf);
FsPermission filePerm = new FsPermission(SYSTEM_FILE_PERMISSION);
// read the count from the jobtracker info file
if (fs.exists(restartFile)) {
fs.delete(tmpRestartFile, false); // delete the tmp file
} else if (fs.exists(tmpRestartFile)) {
// if .rec exists then delete the main file and rename the .rec to main
fs.rename(tmpRestartFile, restartFile); // rename .rec to main file
} else {
// For the very first time the jobtracker will create a jobtracker.info
// file. If the jobtracker has restarted then disable recovery as files'
// needed for recovery are missing.
// disable recovery if this is a restart
shouldRecover = false;
// write the jobtracker.info file
try {
FSDataOutputStream out = FileSystem.create(fs, restartFile,
filePerm);
out.writeInt(0);
out.close();
} catch (IOException ioe) {
LOG.warn("Writing to file " + restartFile + " failed!");
LOG.warn("FileSystem is not ready yet!");
fs.delete(restartFile, false);
throw ioe;
}
return;
}
FSDataInputStream in = fs.open(restartFile);
try {
// read the old count
restartCount = in.readInt();
++restartCount; // increment the restart count
} catch (IOException ioe) {
LOG.warn("System directory is garbled. Failed to read file "
+ restartFile);
LOG.warn("Jobtracker recovery is not possible with garbled"
+ " system directory! Please delete the system directory and"
+ " restart the jobtracker. Note that deleting the system"
+ " directory will result in loss of all the running jobs.");
throw new RuntimeException(ioe);
} finally {
if (in != null) {
in.close();
}
}
// Write back the new restart count and rename the old info file
//TODO This is similar to jobhistory recovery, maybe this common code
// can be factored out.
// write to the tmp file
FSDataOutputStream out = FileSystem.create(fs, tmpRestartFile, filePerm);
out.writeInt(restartCount);
out.close();
// delete the main file
fs.delete(restartFile, false);
// rename the .rec to main file
fs.rename(tmpRestartFile, restartFile);
}
public void recover() {
long recoveryProcessStartTime = clock.getTime();
if (!shouldRecover()) {
// clean up jobs structure
jobsToRecover.clear();
return;
}
LOG.info("Starting the recovery process for " + jobsToRecover.size() +
" jobs ...");
for (JobID jobId : jobsToRecover) {
LOG.info("Submitting job "+ jobId);
try {
Path jobInfoFile = getSystemFileForJob(jobId);
FSDataInputStream in = fs.open(jobInfoFile);
JobInfo token = new JobInfo();
token.readFields(in);
in.close();
UnixUserGroupInformation ugi = new UnixUserGroupInformation(
token.getUser().toString(),
new String[]{UnixUserGroupInformation.DEFAULT_GROUP});
submitJob(token.getJobID(), restartCount,
ugi, token.getJobSubmitDir().toString(), true, null);
recovered++;
} catch (Exception e) {
LOG.warn("Could not recover job " + jobId, e);
}
}
recoveryDuration = clock.getTime() - recoveryProcessStartTime;
hasRecovered = true;
LOG.info("Recovery done! Recoverd " + recovered +" of "+
jobsToRecover.size() + " jobs.");
LOG.info("Recovery Duration (ms):" + recoveryDuration);
}
}
private JobTrackerInstrumentation myInstrumentation;
/////////////////////////////////////////////////////////////////
// The real JobTracker
////////////////////////////////////////////////////////////////
int port;
String localMachine;
private final String trackerIdentifier;
long startTime;
int totalSubmissions = 0;
private int totalMapTaskCapacity;
private int totalReduceTaskCapacity;
private final HostsFileReader hostsReader;
// JobTracker recovery variables
private volatile boolean hasRecovered = false;
private volatile long recoveryDuration;
//
// Properties to maintain while running Jobs and Tasks:
//
// 1. Each Task is always contained in a single Job. A Job succeeds when all its
// Tasks are complete.
//
// 2. Every running or successful Task is assigned to a Tracker. Idle Tasks are not.
//
// 3. When a Tracker fails, all of its assigned Tasks are marked as failures.
//
// 4. A Task might need to be reexecuted if it (or the machine it's hosted on) fails
// before the Job is 100% complete. Sometimes an upstream Task can fail without
// reexecution if all downstream Tasks that require its output have already obtained
// the necessary files.
//
// All the known jobs. (jobid->JobInProgress)
Map<JobID, JobInProgress> jobs = new TreeMap<JobID, JobInProgress>();
// (trackerID --> list of jobs to cleanup)
Map<String, Set<JobID>> trackerToJobsToCleanup =
new HashMap<String, Set<JobID>>();
// (trackerID --> list of tasks to cleanup)
Map<String, Set<TaskAttemptID>> trackerToTasksToCleanup =
new HashMap<String, Set<TaskAttemptID>>();
// All the known TaskInProgress items, mapped to by taskids (taskid->TIP)
Map<TaskAttemptID, TaskInProgress> taskidToTIPMap =
new TreeMap<TaskAttemptID, TaskInProgress>();
// (taskid --> trackerID)
TreeMap<TaskAttemptID, String> taskidToTrackerMap = new TreeMap<TaskAttemptID, String>();
// (trackerID->TreeSet of taskids running at that tracker)
TreeMap<String, Set<TaskAttemptID>> trackerToTaskMap =
new TreeMap<String, Set<TaskAttemptID>>();
// (trackerID -> TreeSet of completed taskids running at that tracker)
TreeMap<String, Set<TaskAttemptID>> trackerToMarkedTasksMap =
new TreeMap<String, Set<TaskAttemptID>>();
// (trackerID --> last sent HeartBeatResponse)
Map<String, HeartbeatResponse> trackerToHeartbeatResponseMap =
new TreeMap<String, HeartbeatResponse>();
// (hostname --> Node (NetworkTopology))
Map<String, Node> hostnameToNodeMap =
Collections.synchronizedMap(new TreeMap<String, Node>());
// (hostname --> Set(tasktracker))
// This is used to keep track of all trackers running on one host. While
// decommissioning the host, all the trackers on the host will be lost.
Map<String, Set<TaskTracker>> hostnameToTaskTracker =
Collections.synchronizedMap(new TreeMap<String, Set<TaskTracker>>());
// Number of resolved entries
int numResolved;
private FaultyTrackersInfo faultyTrackers = new FaultyTrackersInfo();
private JobTrackerStatistics statistics =
new JobTrackerStatistics();
//
// Watch and expire TaskTracker objects using these structures.
// We can map from Name->TaskTrackerStatus, or we can expire by time.
//
int totalMaps = 0;
int totalReduces = 0;
private int occupiedMapSlots = 0;
private int occupiedReduceSlots = 0;
private int reservedMapSlots = 0;
private int reservedReduceSlots = 0;
private HashMap<String, TaskTracker> taskTrackers =
new HashMap<String, TaskTracker>();
Map<String,Integer>uniqueHostsMap = new ConcurrentHashMap<String, Integer>();
ExpireTrackers expireTrackers = new ExpireTrackers();
Thread expireTrackersThread = null;
RetireJobs retireJobs = new RetireJobs();
int retiredJobsCacheSize;
ExpireLaunchingTasks expireLaunchingTasks = new ExpireLaunchingTasks();
Thread expireLaunchingTaskThread = new Thread(expireLaunchingTasks,
"expireLaunchingTasks");
CompletedJobStatusStore completedJobStatusStore;
Thread completedJobsStoreThread = null;
RecoveryManager recoveryManager;
/**
* It might seem like a bug to maintain a TreeSet of tasktracker objects,
* which can be updated at any time. But that's not what happens! We
* only update status objects in the taskTrackers table. Status objects
* are never updated once they enter the expiry queue. Instead, we wait
* for them to expire and remove them from the expiry queue. If a status
* object has been updated in the taskTracker table, the latest status is
* reinserted. Otherwise, we assume the tracker has expired.
*/
TreeSet<TaskTrackerStatus> trackerExpiryQueue =
new TreeSet<TaskTrackerStatus>(
new Comparator<TaskTrackerStatus>() {
public int compare(TaskTrackerStatus p1, TaskTrackerStatus p2) {
if (p1.getLastSeen() < p2.getLastSeen()) {
return -1;
} else if (p1.getLastSeen() > p2.getLastSeen()) {
return 1;
} else {
return (p1.getTrackerName().compareTo(p2.getTrackerName()));
}
}
}
);
// Used to provide an HTML view on Job, Task, and TaskTracker structures
HttpServer infoServer;
int infoPort;
Server interTrackerServer;
// Some jobs are stored in a local system directory. We can delete
// the files when we're done with the job.
static final String SUBDIR = "jobTracker";
FileSystem fs = null;
Path systemDir = null;
JobConf conf;
private UserGroupInformation mrOwner;
private String supergroup;
long limitMaxMemForMapTasks;
long limitMaxMemForReduceTasks;
long memSizeForMapSlotOnJT;
long memSizeForReduceSlotOnJT;
private final QueueManager queueManager;
//TO BE USED BY TEST CLASSES ONLY
//ONLY BUILD THE STATE WHICH IS REQUIRED BY TESTS
JobTracker() {
hostsReader = null;
retiredJobsCacheSize = 0;
infoServer = null;
queueManager = null;
supergroup = null;
taskScheduler = null;
trackerIdentifier = null;
recoveryManager = null;
jobHistory = null;
completedJobStatusStore = null;
tasktrackerExpiryInterval = 0;
myInstrumentation = new JobTrackerMetricsInst(this, new JobConf());
mrOwner = null;
defaultStagingBaseDir = "/Users";
}
JobTracker(JobConf conf)
throws IOException,InterruptedException, LoginException {
this(conf, new Clock());
}
/**
* Create the JobTracker, based on the configuration.
* This does not start the service
* @param conf configuration to use
* @param clock clock to use
* @throws IOException on problems initializing the tracker
*/
JobTracker(JobConf conf, Clock clock)
throws IOException, InterruptedException, LoginException {
this(conf, clock, generateNewIdentifier());
}
JobTracker(JobConf conf, Clock newClock, String jobtrackerIdentifier)
throws IOException, InterruptedException, LoginException {
clock = newClock;
mrOwner = UnixUserGroupInformation.login(conf);
supergroup = conf.get(JT_SUPERGROUP, "supergroup");
LOG.info("Starting jobtracker with owner as " + mrOwner.getUserName()
+ " and supergroup as " + supergroup);
this.conf = conf;
setConf(conf);
//
// Grab some static constants
//
tasktrackerExpiryInterval =
conf.getLong(JT_TRACKER_EXPIRY_INTERVAL, 10 * 60 * 1000);
retiredJobsCacheSize = conf.getInt(JT_RETIREJOB_CACHE_SIZE, 1000);
MAX_BLACKLISTS_PER_TRACKER =
conf.getInt(JTConfig.JT_MAX_TRACKER_BLACKLISTS, 4);
NUM_HEARTBEATS_IN_SECOND =
conf.getInt(JT_HEARTBEATS_IN_SECOND, DEFAULT_NUM_HEARTBEATS_IN_SECOND);
if (NUM_HEARTBEATS_IN_SECOND < MIN_NUM_HEARTBEATS_IN_SECOND) {
NUM_HEARTBEATS_IN_SECOND = DEFAULT_NUM_HEARTBEATS_IN_SECOND;
}
HEARTBEATS_SCALING_FACTOR =
conf.getFloat(JT_HEARTBEATS_SCALING_FACTOR,
DEFAULT_HEARTBEATS_SCALING_FACTOR);
if (HEARTBEATS_SCALING_FACTOR < MIN_HEARTBEATS_SCALING_FACTOR) {
HEARTBEATS_SCALING_FACTOR = DEFAULT_HEARTBEATS_SCALING_FACTOR;
}
//This configuration is there solely for tuning purposes and
//once this feature has been tested in real clusters and an appropriate
//value for the threshold has been found, this config might be taken out.
AVERAGE_BLACKLIST_THRESHOLD = conf.getFloat(JTConfig.JT_AVG_BLACKLIST_THRESHOLD, 0.5f);
// This is a directory of temporary submission files. We delete it
// on startup, and can delete any files that we're done with
initializeTaskMemoryRelatedConfig();
// Read the hosts/exclude files to restrict access to the jobtracker.
this.hostsReader = new HostsFileReader(conf.get(JTConfig.JT_HOSTS_FILENAME, ""),
conf.get(JTConfig.JT_HOSTS_EXCLUDE_FILENAME, ""));
Configuration queuesConf = new Configuration(this.conf);
queueManager = new QueueManager(queuesConf);
this.trackerIdentifier = jobtrackerIdentifier;
// Create the scheduler
Class<? extends TaskScheduler> schedulerClass
= conf.getClass(JT_TASK_SCHEDULER,
JobQueueTaskScheduler.class, TaskScheduler.class);
taskScheduler = (TaskScheduler) ReflectionUtils.newInstance(schedulerClass, conf);
//LOOK AT THIS TODO
taskScheduler.setTaskTrackerManager(this);
}
/**
* This contains the startup logic moved out of the constructor.
* It must never be called directly. Instead call {@link Service#start()} and
* let service decide whether to invoke this method once and once only.
*
* Although most of the intialization work has been performed, the
* JobTracker does not go live until {@link #offerService()} is called.
* accordingly, JobTracker does not enter the Live state here.
* @throws IOException for any startup problems
* @throws InterruptedException if the thread was interrupted on startup
*/
@Override
protected void innerStart() throws IOException, InterruptedException {
// This is a directory of temporary submission files. We delete it
// on startup, and can delete any files that we're done with
JobConf jobConf = new JobConf(conf);
// Set ports, start RPC servers, setup security policy etc.
InetSocketAddress addr = getAddress(conf);
this.localMachine = addr.getHostName();
this.port = addr.getPort();
// Set service-level authorization security policy
if (conf.getBoolean(
ServiceAuthorizationManager.SERVICE_AUTHORIZATION_CONFIG, false)) {
PolicyProvider policyProvider =
(PolicyProvider)(ReflectionUtils.newInstance(
conf.getClass(PolicyProvider.POLICY_PROVIDER_CONFIG,
MapReducePolicyProvider.class, PolicyProvider.class),
conf));
SecurityUtil.setPolicy(new ConfiguredPolicy(conf, policyProvider));
}
int handlerCount = conf.getInt(JT_IPC_HANDLER_COUNT, 10);
this.interTrackerServer = RPC.getServer(this, addr.getHostName(), addr.getPort(), handlerCount, false, conf);
if (LOG.isDebugEnabled()) {
Properties p = System.getProperties();
for (Iterator it = p.keySet().iterator(); it.hasNext();) {
String key = (String) it.next();
String val = p.getProperty(key);
LOG.debug("Property '" + key + "' is " + val);
}
}
InetSocketAddress infoSocAddr = NetUtils.createSocketAddr(
conf.get(JT_HTTP_ADDRESS, "0.0.0.0:50030"));
String infoBindAddress = infoSocAddr.getHostName();
int tmpInfoPort = infoSocAddr.getPort();
this.startTime = clock.getTime();
infoServer = new HttpServer("job", infoBindAddress, tmpInfoPort,
tmpInfoPort == 0, conf);
infoServer.setAttribute("job.tracker", this);
// initialize history parameters.
jobHistory = new JobHistory();
jobHistory.init(this, conf, this.localMachine, this.startTime);
infoServer.addServlet("reducegraph", "/taskgraph", TaskGraphServlet.class);
infoServer.start();
// Initialize instrumentation
//this operation is synchronized to stop findbugs warning of inconsistent
//access
synchronized (this) {
JobTrackerInstrumentation tmp;
Class<? extends JobTrackerInstrumentation> metricsInst =
getInstrumentationClass(jobConf);
try {
java.lang.reflect.Constructor<? extends JobTrackerInstrumentation> c =
metricsInst.getConstructor(new Class[] {JobTracker.class, JobConf.class} );
tmp = c.newInstance(this, jobConf);
} catch(Exception e) {
//Reflection can throw lots of exceptions -- handle them all by
//falling back on the default.
LOG.error("failed to initialize job tracker metrics", e);
tmp = new JobTrackerMetricsInst(this, jobConf);
}
myInstrumentation = tmp;
}
// The rpc/web-server ports can be ephemeral ports...
// ... ensure we have the correct info
this.port = interTrackerServer.getListenerAddress().getPort();
this.conf.set(JT_IPC_ADDRESS, (this.localMachine + ":" + this.port));
LOG.info("JobTracker up at: " + this.port);
this.infoPort = this.infoServer.getPort();
this.conf.set(JT_HTTP_ADDRESS,
infoBindAddress + ":" + this.infoPort);
LOG.info("JobTracker webserver: " + this.infoServer.getPort());
// start the recovery manager
recoveryManager = new RecoveryManager();
while (!Thread.currentThread().isInterrupted()) {
try {
// if we haven't contacted the namenode go ahead and do it
if (fs == null) {
fs = FileSystem.get(conf);
if(fs == null) {
throw new IllegalStateException("Unable to bind to the filesystem");
}
}
// clean up the system dir, which will only work if hdfs is out of
// safe mode
if(systemDir == null) {
systemDir = new Path(getSystemDir());
}
try {
FileStatus systemDirStatus = fs.getFileStatus(systemDir);
if (!systemDirStatus.getOwner().equals(mrOwner.getUserName())) {
throw new AccessControlException("The systemdir " + systemDir +
" is not owned by " + mrOwner.getUserName());
}
if (!systemDirStatus.getPermission().equals(SYSTEM_DIR_PERMISSION)) {
LOG.warn("Incorrect permissions on " + systemDir +
". Setting it to " + SYSTEM_DIR_PERMISSION);
fs.setPermission(systemDir, SYSTEM_DIR_PERMISSION);
}
} catch (FileNotFoundException fnf) {} //ignore
// Make sure that the backup data is preserved
FileStatus[] systemDirData;
try {
systemDirData = fs.listStatus(this.systemDir);
} catch (FileNotFoundException fnfe) {
systemDirData = null;
}
// Check if the history is enabled .. as we can't have persistence with
// history disabled
if (conf.getBoolean(JT_RESTART_ENABLED, false)
&& systemDirData != null) {
for (FileStatus status : systemDirData) {
try {
recoveryManager.addJobForRecovery(status);
} catch (Throwable t) {
LOG.warn("Failed to add the job " + status.getPath().getName(),
t);
}
}
// Check if there are jobs to be recovered
if (recoveryManager.shouldRecover()) {
break; // if there is something to recover else clean the sys dir
}
}
LOG.info("Cleaning up the system directory");
fs.delete(systemDir, true);
if (FileSystem.mkdirs(fs, systemDir,
new FsPermission(SYSTEM_DIR_PERMISSION))) {
break;
}
LOG.error("Mkdirs failed to create " + systemDir);
} catch (AccessControlException ace) {
LOG.warn("Failed to operate on " + JTConfig.JT_SYSTEM_DIR + "(" + systemDir
+ ") because of permissions.");
LOG.warn("Manually delete the " + JTConfig.JT_SYSTEM_DIR + "(" + systemDir
+ ") and then start the JobTracker.");
LOG.warn("Bailing out ... ");
throw ace;
} catch (IOException ie) {
LOG.info("problem cleaning system directory: " + systemDir + ": " + ie,
ie);
}
try {
Thread.sleep(FS_ACCESS_RETRY_PERIOD);
} catch (InterruptedException e) {
throw new IOException("Interrupted during system directory cleanup ",
e);
}
}
if (Thread.currentThread().isInterrupted()) {
throw new IOException("Interrupted during startup");
}
// Same with 'localDir' except it's always on the local disk.
asyncDiskService = new MRAsyncDiskService(FileSystem.getLocal(conf), conf.getLocalDirs());
asyncDiskService.moveAndDeleteFromEachVolume(SUBDIR);
// Initialize history DONE folder
jobHistory.initDone(conf, fs);
String historyLogDir =
jobHistory.getCompletedJobHistoryLocation().toString();
infoServer.setAttribute("historyLogDir", historyLogDir);
FileSystem historyFS = new Path(historyLogDir).getFileSystem(conf);
infoServer.setAttribute("fileSys", historyFS);
this.dnsToSwitchMapping = ReflectionUtils.newInstance(
conf.getClass("topology.node.switch.mapping.impl", ScriptBasedMapping.class,
DNSToSwitchMapping.class), conf);
this.numTaskCacheLevels = conf.getInt(JT_TASKCACHE_LEVELS,
NetworkTopology.DEFAULT_HOST_LEVEL);
//initializes the job status store
// this operation is synchronized to stop findbugs warning of inconsistent
// access
synchronized (this) {
completedJobStatusStore = new CompletedJobStatusStore(conf);
}
Path homeDir = fs.getHomeDirectory();
defaultStagingBaseDir = homeDir.getParent().toString();
}
private static SimpleDateFormat getDateFormat() {
return new SimpleDateFormat("yyyyMMddHHmm");
}
private static String generateNewIdentifier() {
return getDateFormat().format(new Date());
}
static boolean validateIdentifier(String id) {
try {
// the jobtracker id should be 'date' parseable
getDateFormat().parse(id);
return true;
} catch (ParseException pe) {}
return false;
}
static boolean validateJobNumber(String id) {
try {
// the job number should be integer parseable
Integer.parseInt(id);
return true;
} catch (IllegalArgumentException pe) {}
return false;
}
/**
* Whether the JT has recovered upon restart
*/
public boolean hasRecovered() {
return hasRecovered;
}
/**
* How long the jobtracker took to recover from restart.
*/
public long getRecoveryDuration() {
return recoveryDuration;
}
/**
* Get JobTracker's FileSystem. This is the filesystem for mapreduce.system.dir.
*/
FileSystem getFileSystem() {
return fs;
}
/**
* Get the FileSystem for the given path. This can be used to resolve
* filesystem for job history, local job files or mapreduce.system.dir path.
*/
FileSystem getFileSystem(Path path) throws IOException {
return path.getFileSystem(conf);
}
/**
* Get JobTracker's LocalFileSystem handle. This is used by jobs for
* localizing job files to the local disk.
*/
LocalFileSystem getLocalFileSystem() throws IOException {
return FileSystem.getLocal(conf);
}
TaskScheduler getScheduler() {
return taskScheduler;
}
public static Class<? extends JobTrackerInstrumentation> getInstrumentationClass(Configuration conf) {
return conf.getClass(JT_INSTRUMENTATION,
JobTrackerMetricsInst.class, JobTrackerInstrumentation.class);
}
public static void setInstrumentationClass(Configuration conf, Class<? extends JobTrackerInstrumentation> t) {
conf.setClass(JT_INSTRUMENTATION,
t, JobTrackerInstrumentation.class);
}
JobTrackerInstrumentation getInstrumentation() {
return myInstrumentation;
}
public static InetSocketAddress getAddress(Configuration conf) {
String jobTrackerStr =
conf.get(JT_IPC_ADDRESS, "localhost:8012");
return NetUtils.createSocketAddr(jobTrackerStr);
}
void startExpireTrackersThread() {
this.expireTrackersThread = new Thread(this.expireTrackers, "expireTrackers");
this.expireTrackersThread.start();
}
/**
* Run forever.
* Change the system state to indicate that we are live
* @throws InterruptedException interrupted operations
* @throws IOException IO Problems
*/
public void offerService() throws InterruptedException, IOException {
if(getServiceState() == ServiceState.LIVE) {
//catch re-entrancy by returning early
return;
}
// Prepare for recovery. This is done irrespective of the status of restart
// flag.
while (true) {
try {
recoveryManager.updateRestartCount();
break;
} catch (IOException ioe) {
LOG.warn("Failed to initialize recovery manager. ", ioe);
// wait for some time
Thread.sleep(FS_ACCESS_RETRY_PERIOD);
LOG.warn("Retrying...");
}
}
//now we are live
enterLiveState();
taskScheduler.start();
recoveryManager.recover();
// refresh the node list as the recovery manager might have added
// disallowed trackers
refreshHosts();
startExpireTrackersThread();
expireLaunchingTaskThread.start();
synchronized (this) {
//this is synchronized to stop findbugs warning
if (completedJobStatusStore.isActive()) {
completedJobsStoreThread = new Thread(completedJobStatusStore,
"completedjobsStore-housekeeper");
completedJobsStoreThread.start();
}
}
LOG.info("Starting interTrackerServer");
// start the inter-tracker server once the jt is ready
this.interTrackerServer.start();
LOG.info("Starting RUNNING");
this.interTrackerServer.join();
LOG.info("Stopped interTrackerServer");
}
/////////////////////////////////////////////////////
// Service Lifecycle
/////////////////////////////////////////////////////
/**
* This service shuts down by stopping the
* {@link JobEndNotifier} and then closing down the job
* tracker
*
* @throws IOException exceptions which will be logged
*/
@Override
protected void innerClose() throws IOException {
try {
JobEndNotifier.stopNotifier();
} finally {
closeJobTracker();
}
}
/**
* Close down all the Job tracker threads, and the
* task scheduler.
* This was package scoped, but has been made private so that
* it does not get used. Callers should call {@link #close()} to
* stop a JobTracker
* @throws IOException if problems occur
*/
private void closeJobTracker() throws IOException {
if (this.infoServer != null) {
LOG.info("Stopping infoServer");
try {
this.infoServer.stop();
infoServer = null;
} catch (Exception ex) {
LOG.warn("Exception shutting down JobTracker", ex);
}
}
if (this.interTrackerServer != null) {
LOG.info("Stopping interTrackerServer");
this.interTrackerServer.stop();
interTrackerServer = null;
}
stopExpireTrackersThread();
if (taskScheduler != null) {
taskScheduler.terminate();
taskScheduler = null;
}
retireThread("expireLaunchingTasks", expireLaunchingTaskThread);
expireLaunchingTaskThread = null;
retireThread("completedJobsStore thread", completedJobsStoreThread);
completedJobsStoreThread = null;
LOG.info("stopped all jobtracker services");
}
void stopExpireTrackersThread() {
retireThread("expireTrackers", expireTrackersThread);
expireTrackersThread = null;
}
/**
* Retire a named thread if it is not null and still alive. The thread will be
* interruped and then joined.
*
* @param name thread name for log messages
* @param thread thread -can be null.
* @return true if the thread was shut down; false implies this thread was
* interrupted.
*/
protected boolean retireThread(String name, Thread thread) {
if (thread != null && thread.isAlive()) {
LOG.info("Stopping " + name);
thread.interrupt();
try {
thread.join();
} catch (InterruptedException ex) {
LOG.info("interruped during " + name + " shutdown", ex);
return false;
}
}
return true;
}
/**
* Close the filesystem without raising an exception. At the end of this
* method, fs==null.
* Warning: closing the FS may make it unusable for other clients in the same JVM.
*/
protected synchronized void closeTheFilesystemQuietly() {
if (fs != null) {
try {
fs.close();
} catch (IOException e) {
LOG.warn("When closing the filesystem: " + e, e);
}
fs = null;
}
if (jobHistory != null) {
jobHistory.shutDown();
}
LOG.info("stopped all jobtracker services");
return;
}
/**
* {@inheritDoc}
*
* @return the name of this service
*/
@Override
public String getServiceName() {
return "JobTracker";
}
/**
* Get the current number of trackers.
* This includes blacklisted trackers
* @return the number of task trackers
*/
@Override
public int getLiveWorkerCount() {
return taskTrackers.size();
}
/**
* Return a string that is useful in logs and debugging
* @return state of the job tracker
*/
@Override
public String toString() {
return super.toString()
+ " http://" + conf.get("mapred.job.tracker.http.address") + "/ "
+ (interTrackerServer != null
? ("ipc://" + interTrackerServer.getListenerAddress() + "/ ")
: "")
+ "workers=" + getLiveWorkerCount();
}
///////////////////////////////////////////////////////
// Maintain lookup tables; called by JobInProgress
// and TaskInProgress
///////////////////////////////////////////////////////
void createTaskEntry(TaskAttemptID taskid, String taskTracker, TaskInProgress tip) {
LOG.info("Adding task (" + tip.getAttemptType(taskid) + ") " +
"'" + taskid + "' to tip " +
tip.getTIPId() + ", for tracker '" + taskTracker + "'");
// taskid --> tracker
taskidToTrackerMap.put(taskid, taskTracker);
// tracker --> taskid
Set<TaskAttemptID> taskset = trackerToTaskMap.get(taskTracker);
if (taskset == null) {
taskset = new TreeSet<TaskAttemptID>();
trackerToTaskMap.put(taskTracker, taskset);
}
taskset.add(taskid);
// taskid --> TIP
taskidToTIPMap.put(taskid, tip);
}
void removeTaskEntry(TaskAttemptID taskid) {
// taskid --> tracker
String tracker = taskidToTrackerMap.remove(taskid);
// tracker --> taskid
if (tracker != null) {
Set<TaskAttemptID> trackerSet = trackerToTaskMap.get(tracker);
if (trackerSet != null) {
trackerSet.remove(taskid);
}
}
// taskid --> TIP
if (taskidToTIPMap.remove(taskid) != null) {
// log the task removal in case of success
LOG.info("Removing task '" + taskid + "'");
}
}
/**
* Mark a 'task' for removal later.
* This function assumes that the JobTracker is locked on entry.
*
* @param taskTracker the tasktracker at which the 'task' was running
* @param taskid completed (success/failure/killed) task
*/
void markCompletedTaskAttempt(String taskTracker, TaskAttemptID taskid) {
// tracker --> taskid
Set<TaskAttemptID> taskset = trackerToMarkedTasksMap.get(taskTracker);
if (taskset == null) {
taskset = new TreeSet<TaskAttemptID>();
trackerToMarkedTasksMap.put(taskTracker, taskset);
}
taskset.add(taskid);
LOG.debug("Marked '" + taskid + "' from '" + taskTracker + "'");
}
/**
* Mark all 'non-running' jobs of the job for pruning.
* This function assumes that the JobTracker is locked on entry.
*
* @param job the completed job
*/
void markCompletedJob(JobInProgress job) {
for (TaskInProgress tip : job.getTasks(TaskType.JOB_SETUP)) {
for (TaskStatus taskStatus : tip.getTaskStatuses()) {
if (taskStatus.getRunState() != TaskStatus.State.RUNNING &&
taskStatus.getRunState() != TaskStatus.State.COMMIT_PENDING &&
taskStatus.getRunState() != TaskStatus.State.UNASSIGNED) {
markCompletedTaskAttempt(taskStatus.getTaskTracker(),
taskStatus.getTaskID());
}
}
}
for (TaskInProgress tip : job.getTasks(TaskType.MAP)) {
for (TaskStatus taskStatus : tip.getTaskStatuses()) {
if (taskStatus.getRunState() != TaskStatus.State.RUNNING &&
taskStatus.getRunState() != TaskStatus.State.COMMIT_PENDING &&
taskStatus.getRunState() != TaskStatus.State.FAILED_UNCLEAN &&
taskStatus.getRunState() != TaskStatus.State.KILLED_UNCLEAN &&
taskStatus.getRunState() != TaskStatus.State.UNASSIGNED) {
markCompletedTaskAttempt(taskStatus.getTaskTracker(),
taskStatus.getTaskID());
}
}
}
for (TaskInProgress tip : job.getTasks(TaskType.REDUCE)) {
for (TaskStatus taskStatus : tip.getTaskStatuses()) {
if (taskStatus.getRunState() != TaskStatus.State.RUNNING &&
taskStatus.getRunState() != TaskStatus.State.COMMIT_PENDING &&
taskStatus.getRunState() != TaskStatus.State.FAILED_UNCLEAN &&
taskStatus.getRunState() != TaskStatus.State.KILLED_UNCLEAN &&
taskStatus.getRunState() != TaskStatus.State.UNASSIGNED) {
markCompletedTaskAttempt(taskStatus.getTaskTracker(),
taskStatus.getTaskID());
}
}
}
}
/**
* Remove all 'marked' tasks running on a given {@link TaskTracker}
* from the {@link JobTracker}'s data-structures.
* This function assumes that the JobTracker is locked on entry.
*
* @param taskTracker tasktracker whose 'non-running' tasks are to be purged
*/
void removeMarkedTasks(String taskTracker) {
// Purge all the 'marked' tasks which were running at taskTracker
Set<TaskAttemptID> markedTaskSet =
trackerToMarkedTasksMap.get(taskTracker);
if (markedTaskSet != null) {
for (TaskAttemptID taskid : markedTaskSet) {
removeTaskEntry(taskid);
if (LOG.isDebugEnabled()) {
LOG.debug("Removed marked completed task '" + taskid + "' from '" +
taskTracker + "'");
}
}
// Clear
trackerToMarkedTasksMap.remove(taskTracker);
}
}
/**
* Call {@link #removeTaskEntry(String)} for each of the
* job's tasks.
* When the job is retiring we can afford to nuke all it's tasks
*
* @param job the job about to be 'retired'
*/
synchronized void removeJobTasks(JobInProgress job) {
// iterate over all the task types
for (TaskType type : TaskType.values()) {
// iterate over all the tips of the type under consideration
for (TaskInProgress tip : job.getTasks(type)) {
// iterate over all the task-ids in the tip under consideration
for (TaskAttemptID id : tip.getAllTaskAttemptIDs()) {
// remove the task-id entry from the jobtracker
removeTaskEntry(id);
}
}
}
}
/**
* Safe clean-up all data structures at the end of the
* job (success/failure/killed).
* Here we also ensure that for a given user we maintain
* information for only MAX_COMPLETE_USER_JOBS_IN_MEMORY jobs
* on the JobTracker.
*
* @param job completed job.
*/
synchronized void finalizeJob(JobInProgress job) {
// Mark the 'non-running' tasks for pruning
markCompletedJob(job);
JobEndNotifier.registerNotification(job.getJobConf(), job.getStatus());
// start the merge of log files
JobID id = job.getStatus().getJobID();
// mark the job as completed
try {
jobHistory.markCompleted(id);
} catch (IOException ioe) {
LOG.info("Failed to mark job " + id + " as completed!", ioe);
}
final JobTrackerInstrumentation metrics = getInstrumentation();
metrics.finalizeJob(conf, id);
// mark the job for cleanup at all the trackers
addJobForCleanup(id);
// add the blacklisted trackers to potentially faulty list
if (job.getStatus().getRunState() == JobStatus.SUCCEEDED) {
if (job.getNoOfBlackListedTrackers() > 0) {
for (String hostName : job.getBlackListedTrackers()) {
faultyTrackers.incrementFaults(hostName);
}
}
}
}
///////////////////////////////////////////////////////
// Accessors for objects that want info on jobs, tasks,
// trackers, etc.
///////////////////////////////////////////////////////
public int getTotalSubmissions() {
return totalSubmissions;
}
public String getJobTrackerMachine() {
return localMachine;
}
/**
* Get the unique identifier (ie. timestamp) of this job tracker start.
* @return a string with a unique identifier
*/
public String getTrackerIdentifier() {
return trackerIdentifier;
}
public int getTrackerPort() {
return port;
}
public int getInfoPort() {
return infoPort;
}
public long getStartTime() {
return startTime;
}
public Vector<JobInProgress> runningJobs() {
Vector<JobInProgress> v = new Vector<JobInProgress>();
for (Iterator it = jobs.values().iterator(); it.hasNext();) {
JobInProgress jip = (JobInProgress) it.next();
JobStatus status = jip.getStatus();
if (status.getRunState() == JobStatus.RUNNING) {
v.add(jip);
}
}
return v;
}
/**
* Version that is called from a timer thread, and therefore needs to be
* careful to synchronize.
*/
public synchronized List<JobInProgress> getRunningJobs() {
synchronized (jobs) {
return runningJobs();
}
}
public Vector<JobInProgress> failedJobs() {
Vector<JobInProgress> v = new Vector<JobInProgress>();
for (Iterator it = jobs.values().iterator(); it.hasNext();) {
JobInProgress jip = (JobInProgress) it.next();
JobStatus status = jip.getStatus();
if ((status.getRunState() == JobStatus.FAILED)
|| (status.getRunState() == JobStatus.KILLED)) {
v.add(jip);
}
}
return v;
}
public synchronized List<JobInProgress> getFailedJobs() {
synchronized (jobs) {
return failedJobs();
}
}
public Vector<JobInProgress> completedJobs() {
Vector<JobInProgress> v = new Vector<JobInProgress>();
for (Iterator it = jobs.values().iterator(); it.hasNext();) {
JobInProgress jip = (JobInProgress) it.next();
JobStatus status = jip.getStatus();
if (status.getRunState() == JobStatus.SUCCEEDED) {
v.add(jip);
}
}
return v;
}
public synchronized List<JobInProgress> getCompletedJobs() {
synchronized (jobs) {
return completedJobs();
}
}
/**
* Get all the task trackers in the cluster
*
* @return {@link Collection} of {@link TaskTrackerStatus}
*/
// lock to taskTrackers should hold JT lock first.
public synchronized Collection<TaskTrackerStatus> taskTrackers() {
Collection<TaskTrackerStatus> ttStatuses;
synchronized (taskTrackers) {
ttStatuses =
new ArrayList<TaskTrackerStatus>(taskTrackers.values().size());
for (TaskTracker tt : taskTrackers.values()) {
ttStatuses.add(tt.getStatus());
}
}
return ttStatuses;
}
/**
* Get the active task tracker statuses in the cluster
*
* @return {@link Collection} of active {@link TaskTrackerStatus}
*/
// This method is synchronized to make sure that the locking order
// "taskTrackers lock followed by faultyTrackers.potentiallyFaultyTrackers
// lock" is under JobTracker lock to avoid deadlocks.
synchronized public Collection<TaskTrackerStatus> activeTaskTrackers() {
Collection<TaskTrackerStatus> activeTrackers =
new ArrayList<TaskTrackerStatus>();
synchronized (taskTrackers) {
for ( TaskTracker tt : taskTrackers.values()) {
TaskTrackerStatus status = tt.getStatus();
if (!faultyTrackers.isBlacklisted(status.getHost())) {
activeTrackers.add(status);
}
}
}
return activeTrackers;
}
/**
* Get the active and blacklisted task tracker names in the cluster. The first
* element in the returned list contains the list of active tracker names.
* The second element in the returned list contains the list of blacklisted
* tracker names.
*/
// This method is synchronized to make sure that the locking order
// "taskTrackers lock followed by faultyTrackers.potentiallyFaultyTrackers
// lock" is under JobTracker lock to avoid deadlocks.
synchronized public List<List<String>> taskTrackerNames() {
List<String> activeTrackers =
new ArrayList<String>();
List<String> blacklistedTrackers =
new ArrayList<String>();
synchronized (taskTrackers) {
for (TaskTracker tt : taskTrackers.values()) {
TaskTrackerStatus status = tt.getStatus();
if (!faultyTrackers.isBlacklisted(status.getHost())) {
activeTrackers.add(status.getTrackerName());
} else {
blacklistedTrackers.add(status.getTrackerName());
}
}
}
List<List<String>> result = new ArrayList<List<String>>(2);
result.add(activeTrackers);
result.add(blacklistedTrackers);
return result;
}
/**
* Get the blacklisted task tracker statuses in the cluster
*
* @return {@link Collection} of blacklisted {@link TaskTrackerStatus}
*/
// This method is synchronized to make sure that the locking order
// "taskTrackers lock followed by faultyTrackers.potentiallyFaultyTrackers
// lock" is under JobTracker lock to avoid deadlocks.
synchronized public Collection<TaskTrackerStatus> blacklistedTaskTrackers() {
Collection<TaskTrackerStatus> blacklistedTrackers =
new ArrayList<TaskTrackerStatus>();
synchronized (taskTrackers) {
for (TaskTracker tt : taskTrackers.values()) {
TaskTrackerStatus status = tt.getStatus();
if (faultyTrackers.isBlacklisted(status.getHost())) {
blacklistedTrackers.add(status);
}
}
}
return blacklistedTrackers;
}
synchronized int getFaultCount(String hostName) {
return faultyTrackers.getFaultCount(hostName);
}
/**
* Get the number of blacklisted trackers across all the jobs
*
* @return
*/
int getBlacklistedTrackerCount() {
return faultyTrackers.numBlacklistedTrackers;
}
/**
* Whether the tracker is blacklisted or not
*
* @param trackerID
*
* @return true if blacklisted, false otherwise
*/
synchronized public boolean isBlacklisted(String trackerID) {
TaskTrackerStatus status = getTaskTrackerStatus(trackerID);
if (status != null) {
return faultyTrackers.isBlacklisted(status.getHost());
}
return false;
}
// lock to taskTrackers should hold JT lock first.
synchronized public TaskTrackerStatus getTaskTrackerStatus(String trackerID) {
TaskTracker taskTracker;
synchronized (taskTrackers) {
taskTracker = taskTrackers.get(trackerID);
}
return (taskTracker == null) ? null : taskTracker.getStatus();
}
// lock to taskTrackers should hold JT lock first.
synchronized public TaskTracker getTaskTracker(String trackerID) {
synchronized (taskTrackers) {
return taskTrackers.get(trackerID);
}
}
JobTrackerStatistics getStatistics() {
return statistics;
}
/**
* Adds a new node to the jobtracker. It involves adding it to the expiry
* thread and adding it for resolution
*
* Assumes JobTracker, taskTrackers and trackerExpiryQueue are locked on entry
*
* @param status Task Tracker's status
*/
void addNewTracker(TaskTracker taskTracker) {
TaskTrackerStatus status = taskTracker.getStatus();
trackerExpiryQueue.add(status);
// Register the tracker if its not registered
String hostname = status.getHost();
if (getNode(status.getTrackerName()) == null) {
// Making the network location resolution inline ..
resolveAndAddToTopology(hostname);
}
// add it to the set of tracker per host
Set<TaskTracker> trackers = hostnameToTaskTracker.get(hostname);
if (trackers == null) {
trackers = Collections.synchronizedSet(new HashSet<TaskTracker>());
hostnameToTaskTracker.put(hostname, trackers);
}
statistics.taskTrackerAdded(status.getTrackerName());
getInstrumentation().addTrackers(1);
LOG.info("Adding tracker " + status.getTrackerName() + " to host "
+ hostname);
trackers.add(taskTracker);
}
public Node resolveAndAddToTopology(String name) {
List <String> tmpList = new ArrayList<String>(1);
tmpList.add(name);
List <String> rNameList = dnsToSwitchMapping.resolve(tmpList);
String rName = rNameList.get(0);
String networkLoc = NodeBase.normalize(rName);
return addHostToNodeMapping(name, networkLoc);
}
private Node addHostToNodeMapping(String host, String networkLoc) {
Node node;
if ((node = clusterMap.getNode(networkLoc+"/"+host)) == null) {
node = new NodeBase(host, networkLoc);
clusterMap.add(node);
if (node.getLevel() < getNumTaskCacheLevels()) {
LOG.fatal("Got a host whose level is: " + node.getLevel() + "."
+ " Should get at least a level of value: "
+ getNumTaskCacheLevels());
try {
stopTracker();
} catch (IOException ie) {
LOG.warn("Exception encountered during shutdown: "
+ StringUtils.stringifyException(ie));
System.exit(-1);
}
}
hostnameToNodeMap.put(host, node);
// Make an entry for the node at the max level in the cache
nodesAtMaxLevel.add(getParentNode(node, getNumTaskCacheLevels() - 1));
}
return node;
}
/**
* Returns a collection of nodes at the max level
*/
public Collection<Node> getNodesAtMaxLevel() {
return nodesAtMaxLevel;
}
public static Node getParentNode(Node node, int level) {
for (int i = 0; i < level; ++i) {
node = node.getParent();
}
return node;
}
/**
* Return the Node in the network topology that corresponds to the hostname
*/
public Node getNode(String name) {
return hostnameToNodeMap.get(name);
}
public int getNumTaskCacheLevels() {
return numTaskCacheLevels;
}
public int getNumResolvedTaskTrackers() {
return numResolved;
}
public int getNumberOfUniqueHosts() {
return uniqueHostsMap.size();
}
public void addJobInProgressListener(JobInProgressListener listener) {
jobInProgressListeners.add(listener);
}
public void removeJobInProgressListener(JobInProgressListener listener) {
jobInProgressListeners.remove(listener);
}
// Update the listeners about the job
// Assuming JobTracker is locked on entry.
void updateJobInProgressListeners(JobChangeEvent event) {
for (JobInProgressListener listener : jobInProgressListeners) {
listener.jobUpdated(event);
}
}
/**
* Return the {@link QueueManager} associated with the JobTracker.
*/
public QueueManager getQueueManager() {
return queueManager;
}
////////////////////////////////////////////////////
// InterTrackerProtocol
////////////////////////////////////////////////////
public String getBuildVersion() throws IOException{
return VersionInfo.getBuildVersion();
}
/**
* The periodic heartbeat mechanism between the {@link TaskTracker} and
* the {@link JobTracker}.
*
* The {@link JobTracker} processes the status information sent by the
* {@link TaskTracker} and responds with instructions to start/stop
* tasks or jobs, and also 'reset' instructions during contingencies.
*/
public synchronized HeartbeatResponse heartbeat(TaskTrackerStatus status,
boolean restarted,
boolean initialContact,
boolean acceptNewTasks,
short responseId)
throws IOException {
if (LOG.isDebugEnabled()) {
LOG.debug("Got heartbeat from: " + status.getTrackerName() +
" (restarted: " + restarted +
" initialContact: " + initialContact +
" acceptNewTasks: " + acceptNewTasks + ")" +
" with responseId: " + responseId);
}
// Make sure heartbeat is from a tasktracker allowed by the jobtracker.
if (!acceptTaskTracker(status)) {
throw new DisallowedTaskTrackerException(status);
}
// First check if the last heartbeat response got through
String trackerName = status.getTrackerName();
long now = clock.getTime();
boolean isBlacklisted = false;
if (restarted) {
faultyTrackers.markTrackerHealthy(status.getHost());
} else {
isBlacklisted =
faultyTrackers.shouldAssignTasksToTracker(status.getHost(), now);
}
HeartbeatResponse prevHeartbeatResponse =
trackerToHeartbeatResponseMap.get(trackerName);
if (initialContact != true) {
// If this isn't the 'initial contact' from the tasktracker,
// there is something seriously wrong if the JobTracker has
// no record of the 'previous heartbeat'; if so, ask the
// tasktracker to re-initialize itself.
if (prevHeartbeatResponse == null) {
// This is the first heartbeat from the old tracker to the newly
// started JobTracker
// Jobtracker might have restarted but no recovery is needed
// otherwise this code should not be reached
LOG.warn("Serious problem, cannot find record of 'previous' " +
"heartbeat for '" + trackerName +
"'; reinitializing the tasktracker");
return new HeartbeatResponse(responseId,
new TaskTrackerAction[] {new ReinitTrackerAction()});
} else {
// It is completely safe to not process a 'duplicate' heartbeat from a
// {@link TaskTracker} since it resends the heartbeat when rpcs are
// lost see {@link TaskTracker.transmitHeartbeat()};
// acknowledge it by re-sending the previous response to let the
// {@link TaskTracker} go forward.
if (prevHeartbeatResponse.getResponseId() != responseId) {
LOG.info("Ignoring 'duplicate' heartbeat from '" +
trackerName + "'; resending the previous 'lost' response");
return prevHeartbeatResponse;
}
}
}
// Process this heartbeat
short newResponseId = (short)(responseId + 1);
status.setLastSeen(now);
if (!processHeartbeat(status, initialContact)) {
if (prevHeartbeatResponse != null) {
trackerToHeartbeatResponseMap.remove(trackerName);
}
return new HeartbeatResponse(newResponseId,
new TaskTrackerAction[] {new ReinitTrackerAction()});
}
// Initialize the response to be sent for the heartbeat
HeartbeatResponse response = new HeartbeatResponse(newResponseId, null);
List<TaskTrackerAction> actions = new ArrayList<TaskTrackerAction>();
isBlacklisted = faultyTrackers.isBlacklisted(status.getHost());
// Check for new tasks to be executed on the tasktracker
if (acceptNewTasks && !isBlacklisted) {
TaskTrackerStatus taskTrackerStatus = getTaskTrackerStatus(trackerName) ;
if (taskTrackerStatus == null) {
LOG.warn("Unknown task tracker polling; ignoring: " + trackerName);
} else {
List<Task> tasks = getSetupAndCleanupTasks(taskTrackerStatus);
if (tasks == null ) {
tasks = taskScheduler.assignTasks(taskTrackers.get(trackerName));
}
if (tasks != null) {
for (Task task : tasks) {
expireLaunchingTasks.addNewTask(task.getTaskID());
LOG.debug(trackerName + " -> LaunchTask: " + task.getTaskID());
actions.add(new LaunchTaskAction(task));
}
}
}
}
// Check for tasks to be killed
List<TaskTrackerAction> killTasksList = getTasksToKill(trackerName);
if (killTasksList != null) {
actions.addAll(killTasksList);
}
// Check for jobs to be killed/cleanedup
List<TaskTrackerAction> killJobsList = getJobsForCleanup(trackerName);
if (killJobsList != null) {
actions.addAll(killJobsList);
}
// Check for tasks whose outputs can be saved
List<TaskTrackerAction> commitTasksList = getTasksToSave(status);
if (commitTasksList != null) {
actions.addAll(commitTasksList);
}
// calculate next heartbeat interval and put in heartbeat response
int nextInterval = getNextHeartbeatInterval();
response.setHeartbeatInterval(nextInterval);
response.setActions(
actions.toArray(new TaskTrackerAction[actions.size()]));
// Update the trackerToHeartbeatResponseMap
trackerToHeartbeatResponseMap.put(trackerName, response);
// Done processing the hearbeat, now remove 'marked' tasks
removeMarkedTasks(trackerName);
return response;
}
/**
* Calculates next heartbeat interval using cluster size.
* Heartbeat interval is incremented by 1 second for every 100 nodes by default.
* @return next heartbeat interval.
*/
public int getNextHeartbeatInterval() {
// get the no of task trackers
int clusterSize = getClusterStatus().getTaskTrackers();
int heartbeatInterval = Math.max(
(int)(1000 * HEARTBEATS_SCALING_FACTOR *
Math.ceil((double)clusterSize /
NUM_HEARTBEATS_IN_SECOND)),
HEARTBEAT_INTERVAL_MIN) ;
return heartbeatInterval;
}
/**
* Return if the specified tasktracker is in the hosts list,
* if one was configured. If none was configured, then this
* returns true.
*/
private boolean inHostsList(TaskTrackerStatus status) {
Set<String> hostsList = hostsReader.getHosts();
return (hostsList.isEmpty() || hostsList.contains(status.getHost()));
}
/**
* Return if the specified tasktracker is in the exclude list.
*/
private boolean inExcludedHostsList(TaskTrackerStatus status) {
Set<String> excludeList = hostsReader.getExcludedHosts();
return excludeList.contains(status.getHost());
}
/**
* Returns true if the tasktracker is in the hosts list and
* not in the exclude list.
*/
private boolean acceptTaskTracker(TaskTrackerStatus status) {
return (inHostsList(status) && !inExcludedHostsList(status));
}
/**
* Update the last recorded status for the given task tracker.
* It assumes that the taskTrackers are locked on entry.
* @param trackerName The name of the tracker
* @param status The new status for the task tracker
* @return Was an old status found?
*/
boolean updateTaskTrackerStatus(String trackerName,
TaskTrackerStatus status) {
TaskTracker tt = getTaskTracker(trackerName);
TaskTrackerStatus oldStatus = (tt == null) ? null : tt.getStatus();
if (oldStatus != null) {
totalMaps -= oldStatus.countMapTasks();
totalReduces -= oldStatus.countReduceTasks();
occupiedMapSlots -= oldStatus.countOccupiedMapSlots();
occupiedReduceSlots -= oldStatus.countOccupiedReduceSlots();
getInstrumentation().decRunningMaps(oldStatus.countMapTasks());
getInstrumentation().decRunningReduces(oldStatus.countReduceTasks());
getInstrumentation().decOccupiedMapSlots(oldStatus.countOccupiedMapSlots());
getInstrumentation().decOccupiedReduceSlots(oldStatus.countOccupiedReduceSlots());
if (!faultyTrackers.isBlacklisted(oldStatus.getHost())) {
int mapSlots = oldStatus.getMaxMapSlots();
totalMapTaskCapacity -= mapSlots;
int reduceSlots = oldStatus.getMaxReduceSlots();
totalReduceTaskCapacity -= reduceSlots;
}
if (status == null) {
taskTrackers.remove(trackerName);
Integer numTaskTrackersInHost =
uniqueHostsMap.get(oldStatus.getHost());
if (numTaskTrackersInHost != null) {
numTaskTrackersInHost --;
if (numTaskTrackersInHost > 0) {
uniqueHostsMap.put(oldStatus.getHost(), numTaskTrackersInHost);
}
else {
uniqueHostsMap.remove(oldStatus.getHost());
}
}
}
}
if (status != null) {
totalMaps += status.countMapTasks();
totalReduces += status.countReduceTasks();
occupiedMapSlots += status.countOccupiedMapSlots();
occupiedReduceSlots += status.countOccupiedReduceSlots();
getInstrumentation().addRunningMaps(status.countMapTasks());
getInstrumentation().addRunningReduces(status.countReduceTasks());
getInstrumentation().addOccupiedMapSlots(status.countOccupiedMapSlots());
getInstrumentation().addOccupiedReduceSlots(status.countOccupiedReduceSlots());
if (!faultyTrackers.isBlacklisted(status.getHost())) {
int mapSlots = status.getMaxMapSlots();
totalMapTaskCapacity += mapSlots;
int reduceSlots = status.getMaxReduceSlots();
totalReduceTaskCapacity += reduceSlots;
}
boolean alreadyPresent = false;
TaskTracker taskTracker = taskTrackers.get(trackerName);
if (taskTracker != null) {
alreadyPresent = true;
} else {
taskTracker = new TaskTracker(trackerName);
}
taskTracker.setStatus(status);
taskTrackers.put(trackerName, taskTracker);
if (LOG.isDebugEnabled()) {
int runningMaps = 0, runningReduces = 0;
int commitPendingMaps = 0, commitPendingReduces = 0;
int unassignedMaps = 0, unassignedReduces = 0;
int miscMaps = 0, miscReduces = 0;
List<TaskStatus> taskReports = status.getTaskReports();
for (Iterator<TaskStatus> it = taskReports.iterator(); it.hasNext();) {
TaskStatus ts = it.next();
boolean isMap = ts.getIsMap();
TaskStatus.State state = ts.getRunState();
if (state == TaskStatus.State.RUNNING) {
if (isMap) { ++runningMaps; }
else { ++runningReduces; }
} else if (state == TaskStatus.State.UNASSIGNED) {
if (isMap) { ++unassignedMaps; }
else { ++unassignedReduces; }
} else if (state == TaskStatus.State.COMMIT_PENDING) {
if (isMap) { ++commitPendingMaps; }
else { ++commitPendingReduces; }
} else {
if (isMap) { ++miscMaps; }
else { ++miscReduces; }
}
}
LOG.debug(trackerName + ": Status -" +
" running(m) = " + runningMaps +
" unassigned(m) = " + unassignedMaps +
" commit_pending(m) = " + commitPendingMaps +
" misc(m) = " + miscMaps +
" running(r) = " + runningReduces +
" unassigned(r) = " + unassignedReduces +
" commit_pending(r) = " + commitPendingReduces +
" misc(r) = " + miscReduces);
}
if (!alreadyPresent) {
Integer numTaskTrackersInHost =
uniqueHostsMap.get(status.getHost());
if (numTaskTrackersInHost == null) {
numTaskTrackersInHost = 0;
}
numTaskTrackersInHost ++;
uniqueHostsMap.put(status.getHost(), numTaskTrackersInHost);
}
}
getInstrumentation().setMapSlots(totalMapTaskCapacity);
getInstrumentation().setReduceSlots(totalReduceTaskCapacity);
return oldStatus != null;
}
// Increment the number of reserved slots in the cluster.
// This method assumes the caller has JobTracker lock.
void incrementReservations(TaskType type, int reservedSlots) {
if (type.equals(TaskType.MAP)) {
reservedMapSlots += reservedSlots;
} else if (type.equals(TaskType.REDUCE)) {
reservedReduceSlots += reservedSlots;
}
}
// Decrement the number of reserved slots in the cluster.
// This method assumes the caller has JobTracker lock.
void decrementReservations(TaskType type, int reservedSlots) {
if (type.equals(TaskType.MAP)) {
reservedMapSlots -= reservedSlots;
} else if (type.equals(TaskType.REDUCE)) {
reservedReduceSlots -= reservedSlots;
}
}
private void updateNodeHealthStatus(TaskTrackerStatus trackerStatus) {
TaskTrackerHealthStatus status = trackerStatus.getHealthStatus();
synchronized (faultyTrackers) {
faultyTrackers.setNodeHealthStatus(trackerStatus.getHost(),
status.isNodeHealthy(), status.getHealthReport());
}
}
/**
* Process incoming heartbeat messages from the task trackers.
*/
synchronized boolean processHeartbeat(
TaskTrackerStatus trackerStatus,
boolean initialContact) {
String trackerName = trackerStatus.getTrackerName();
synchronized (taskTrackers) {
synchronized (trackerExpiryQueue) {
boolean seenBefore = updateTaskTrackerStatus(trackerName,
trackerStatus);
TaskTracker taskTracker = getTaskTracker(trackerName);
if (initialContact) {
// If it's first contact, then clear out
// any state hanging around
if (seenBefore) {
lostTaskTracker(taskTracker);
}
} else {
// If not first contact, there should be some record of the tracker
if (!seenBefore) {
LOG.warn("Status from unknown Tracker : " + trackerName);
updateTaskTrackerStatus(trackerName, null);
return false;
}
}
if (initialContact) {
// if this is lost tracker that came back now, and if it blacklisted
// increment the count of blacklisted trackers in the cluster
if (isBlacklisted(trackerName)) {
faultyTrackers.incrBlackListedTrackers(1);
}
addNewTracker(taskTracker);
}
}
}
updateTaskStatuses(trackerStatus);
updateNodeHealthStatus(trackerStatus);
return true;
}
/**
* A tracker wants to know if any of its Tasks have been
* closed (because the job completed, whether successfully or not)
*/
synchronized List<TaskTrackerAction> getTasksToKill(String taskTracker) {
Set<TaskAttemptID> taskIds = trackerToTaskMap.get(taskTracker);
List<TaskTrackerAction> killList = new ArrayList<TaskTrackerAction>();
if (taskIds != null) {
for (TaskAttemptID killTaskId : taskIds) {
TaskInProgress tip = taskidToTIPMap.get(killTaskId);
if (tip == null) {
continue;
}
if (tip.shouldClose(killTaskId)) {
//
// This is how the JobTracker ends a task at the TaskTracker.
// It may be successfully completed, or may be killed in
// mid-execution.
//
if (!tip.getJob().isComplete()) {
killList.add(new KillTaskAction(killTaskId));
LOG.debug(taskTracker + " -> KillTaskAction: " + killTaskId);
}
}
}
}
// add the stray attempts for uninited jobs
synchronized (trackerToTasksToCleanup) {
Set<TaskAttemptID> set = trackerToTasksToCleanup.remove(taskTracker);
if (set != null) {
for (TaskAttemptID id : set) {
killList.add(new KillTaskAction(id));
}
}
}
return killList;
}
/**
* Add a job to cleanup for the tracker.
*/
private void addJobForCleanup(JobID id) {
for (String taskTracker : taskTrackers.keySet()) {
LOG.debug("Marking job " + id + " for cleanup by tracker " + taskTracker);
synchronized (trackerToJobsToCleanup) {
Set<JobID> jobsToKill = trackerToJobsToCleanup.get(taskTracker);
if (jobsToKill == null) {
jobsToKill = new HashSet<JobID>();
trackerToJobsToCleanup.put(taskTracker, jobsToKill);
}
jobsToKill.add(id);
}
}
}
/**
* A tracker wants to know if any job needs cleanup because the job completed.
*/
private List<TaskTrackerAction> getJobsForCleanup(String taskTracker) {
Set<JobID> jobs = null;
synchronized (trackerToJobsToCleanup) {
jobs = trackerToJobsToCleanup.remove(taskTracker);
}
if (jobs != null) {
// prepare the actions list
List<TaskTrackerAction> killList = new ArrayList<TaskTrackerAction>();
for (JobID killJobId : jobs) {
killList.add(new KillJobAction(killJobId));
LOG.debug(taskTracker + " -> KillJobAction: " + killJobId);
}
return killList;
}
return null;
}
/**
* A tracker wants to know if any of its Tasks can be committed
*/
synchronized List<TaskTrackerAction> getTasksToSave(
TaskTrackerStatus tts) {
List<TaskStatus> taskStatuses = tts.getTaskReports();
if (taskStatuses != null) {
List<TaskTrackerAction> saveList = new ArrayList<TaskTrackerAction>();
for (TaskStatus taskStatus : taskStatuses) {
if (taskStatus.getRunState() == TaskStatus.State.COMMIT_PENDING) {
TaskAttemptID taskId = taskStatus.getTaskID();
TaskInProgress tip = taskidToTIPMap.get(taskId);
if (tip == null) {
continue;
}
if (tip.shouldCommit(taskId)) {
saveList.add(new CommitTaskAction(taskId));
LOG.debug(tts.getTrackerName() +
" -> CommitTaskAction: " + taskId);
}
}
}
return saveList;
}
return null;
}
// returns cleanup tasks first, then setup tasks.
synchronized List<Task> getSetupAndCleanupTasks(
TaskTrackerStatus taskTracker) throws IOException {
int maxMapTasks = taskTracker.getMaxMapSlots();
int maxReduceTasks = taskTracker.getMaxReduceSlots();
int numMaps = taskTracker.countOccupiedMapSlots();
int numReduces = taskTracker.countOccupiedReduceSlots();
int numTaskTrackers = getClusterStatus().getTaskTrackers();
int numUniqueHosts = getNumberOfUniqueHosts();
Task t = null;
synchronized (jobs) {
if (numMaps < maxMapTasks) {
for (Iterator<JobInProgress> it = jobs.values().iterator();
it.hasNext();) {
JobInProgress job = it.next();
t = job.obtainJobCleanupTask(taskTracker, numTaskTrackers,
numUniqueHosts, true);
if (t != null) {
return Collections.singletonList(t);
}
}
for (Iterator<JobInProgress> it = jobs.values().iterator();
it.hasNext();) {
JobInProgress job = it.next();
t = job.obtainTaskCleanupTask(taskTracker, true);
if (t != null) {
return Collections.singletonList(t);
}
}
for (Iterator<JobInProgress> it = jobs.values().iterator();
it.hasNext();) {
JobInProgress job = it.next();
t = job.obtainJobSetupTask(taskTracker, numTaskTrackers,
numUniqueHosts, true);
if (t != null) {
return Collections.singletonList(t);
}
}
}
if (numReduces < maxReduceTasks) {
for (Iterator<JobInProgress> it = jobs.values().iterator();
it.hasNext();) {
JobInProgress job = it.next();
t = job.obtainJobCleanupTask(taskTracker, numTaskTrackers,
numUniqueHosts, false);
if (t != null) {
return Collections.singletonList(t);
}
}
for (Iterator<JobInProgress> it = jobs.values().iterator();
it.hasNext();) {
JobInProgress job = it.next();
t = job.obtainTaskCleanupTask(taskTracker, false);
if (t != null) {
return Collections.singletonList(t);
}
}
for (Iterator<JobInProgress> it = jobs.values().iterator();
it.hasNext();) {
JobInProgress job = it.next();
t = job.obtainJobSetupTask(taskTracker, numTaskTrackers,
numUniqueHosts, false);
if (t != null) {
return Collections.singletonList(t);
}
}
}
}
return null;
}
/**
* Grab the local fs name
*/
public synchronized String getFilesystemName() throws IOException {
if (fs == null) {
throw new IllegalStateException("FileSystem object not available yet");
}
return fs.getUri().toString();
}
public void reportTaskTrackerError(String taskTracker,
String errorClass,
String errorMessage) throws IOException {
LOG.warn("Report from " + taskTracker + ": " + errorMessage);
}
/**
* Remove the job_ from jobids to get the unique string.
*/
static String getJobUniqueString(String jobid) {
return jobid.substring(4);
}
////////////////////////////////////////////////////
// JobSubmissionProtocol
////////////////////////////////////////////////////
/**
* Allocates a new JobId string.
* @deprecated use {@link #getNewJobID()} instead
*/
@Deprecated
public synchronized JobID getNewJobId() throws IOException {
verifyServiceState(ServiceState.LIVE);
return JobID.downgrade(getNewJobID());
}
/**
* Allocates a new JobId string.
*/
public synchronized org.apache.hadoop.mapreduce.JobID getNewJobID()
throws IOException {
return new org.apache.hadoop.mapreduce.JobID(
getTrackerIdentifier(), nextJobId++);
}
/**
* JobTracker.submitJob() kicks off a new job.
*
* Create a 'JobInProgress' object, which contains both JobProfile
* and JobStatus. Those two sub-objects are sometimes shipped outside
* of the JobTracker. But JobInProgress adds info that's useful for
* the JobTracker alone.
*/
public synchronized org.apache.hadoop.mapreduce.JobStatus submitJob(
org.apache.hadoop.mapreduce.JobID jobId,String jobSubmitDir, TokenStorage ts)
throws IOException {
return submitJob(JobID.downgrade(jobId), jobSubmitDir, ts);
}
/**
* JobTracker.submitJob() kicks off a new job.
*
* Create a 'JobInProgress' object, which contains both JobProfile
* and JobStatus. Those two sub-objects are sometimes shipped outside
* of the JobTracker. But JobInProgress adds info that's useful for
* the JobTracker alone.
* @deprecated Use
* {@link #submitJob(org.apache.hadoop.mapreduce.JobID, String, TokenStorage)}
* instead
*/
@Deprecated
public synchronized JobStatus submitJob(
JobID jobId, String jobSubmitDir, TokenStorage ts)
throws IOException {
return submitJob(jobId, 0,
UserGroupInformation.getCurrentUGI(),
jobSubmitDir, false, ts);
}
/**
* Submits either a new job or a job from an earlier run.
*/
private synchronized JobStatus submitJob(org.apache.hadoop.mapreduce.JobID jobID,
int restartCount, UserGroupInformation ugi, String jobSubmitDir,
boolean recovered, TokenStorage ts) throws IOException {
verifyServiceState(ServiceState.LIVE);
JobID jobId = JobID.downgrade(jobID);
if(jobs.containsKey(jobId)) {
//job already running, don't start twice
return jobs.get(jobId).getStatus();
}
//the conversion from String to Text for the UGI's username will
//not be required when we have the UGI to return us the username as
//Text.
JobInfo jobInfo = new JobInfo(jobId, new Text(ugi.getUserName()),
new Path(jobSubmitDir));
JobInProgress job =
new JobInProgress(this, this.conf, restartCount, jobInfo, ts);
String queue = job.getProfile().getQueueName();
if(!(queueManager.getLeafQueueNames().contains(queue))) {
throw new IOException("Queue \"" + queue + "\" does not exist");
}
//check if queue is RUNNING
if(!queueManager.isRunning(queue)) {
throw new IOException("Queue \"" + queue + "\" is not running");
}
try {
checkAccess(job, Queue.QueueOperation.SUBMIT_JOB, ugi);
} catch (IOException ioe) {
LOG.warn("Access denied for user " + job.getJobConf().getUser()
+ ". Ignoring job " + jobId, ioe);
throw ioe;
}
// Check the job if it cannot run in the cluster because of invalid memory
// requirements.
try {
checkMemoryRequirements(job);
} catch (IOException ioe) {
throw ioe;
}
if (!recovered) {
//Store the information in a file so that the job can be recovered
//later (if at all)
Path jobDir = getSystemDirectoryForJob(jobId);
FileSystem.mkdirs(fs, jobDir, new FsPermission(SYSTEM_DIR_PERMISSION));
FSDataOutputStream out = fs.create(getSystemFileForJob(jobId));
jobInfo.write(out);
out.close();
}
return addJob(jobId, job);
}
/**
* Adds a job to the jobtracker. Make sure that the checks are inplace before
* adding a job. This is the core job submission logic
* @param jobId The id for the job submitted which needs to be added
*/
synchronized JobStatus addJob(JobID jobId, JobInProgress job) {
totalSubmissions++;
synchronized (jobs) {
synchronized (taskScheduler) {
jobs.put(job.getProfile().getJobID(), job);
for (JobInProgressListener listener : jobInProgressListeners) {
try {
listener.jobAdded(job);
} catch (IOException ioe) {
LOG.warn("Failed to add and so skipping the job : "
+ job.getJobID() + ". Exception : " + ioe);
}
}
}
}
myInstrumentation.submitJob(job.getJobConf(), jobId);
LOG.info("Job " + jobId + " added successfully for user '"
+ job.getJobConf().getUser() + "' to queue '"
+ job.getJobConf().getQueueName() + "'");
return job.getStatus();
}
// Check whether the specified operation can be performed
// related to the job.
private void checkAccess(JobInProgress job,
Queue.QueueOperation oper)
throws IOException {
// get the user group info
UserGroupInformation ugi = UserGroupInformation.getCurrentUGI();
checkAccess(job, oper, ugi);
}
// use the passed ugi for checking the access
private void checkAccess(JobInProgress job, Queue.QueueOperation oper,
UserGroupInformation ugi) throws IOException {
// get the queue
String queue = job.getProfile().getQueueName();
if (!queueManager.hasAccess(queue, job, oper, ugi)) {
throw new AccessControlException("User "
+ ugi.getUserName()
+ " cannot perform "
+ "operation " + oper + " on queue " + queue +
".\n Please run \"hadoop queue -showacls\" " +
"command to find the queues you have access" +
" to .");
}
}
/**@deprecated use {@link #getClusterStatus(boolean)}*/
@Deprecated
public synchronized ClusterStatus getClusterStatus() {
return getClusterStatus(false);
}
public synchronized ClusterStatus getClusterStatus(boolean detailed) {
synchronized (taskTrackers) {
//backport the service state into the job tracker state
State state = getServiceState() == ServiceState.LIVE ?
State.RUNNING :
State.INITIALIZING;
if (detailed) {
List<List<String>> trackerNames = taskTrackerNames();
Collection<BlackListInfo> blackListedTrackers = getBlackListedTrackers();
return new ClusterStatus(trackerNames.get(0),
blackListedTrackers,
tasktrackerExpiryInterval,
totalMaps,
totalReduces,
totalMapTaskCapacity,
totalReduceTaskCapacity,
state, getExcludedNodes().size()
);
} else {
return new ClusterStatus(taskTrackers.size() -
getBlacklistedTrackerCount(),
getBlacklistedTrackerCount(),
tasktrackerExpiryInterval,
totalMaps,
totalReduces,
totalMapTaskCapacity,
totalReduceTaskCapacity,
state, getExcludedNodes().size());
}
}
}
public synchronized ClusterMetrics getClusterMetrics() {
return new ClusterMetrics(totalMaps,
totalReduces, occupiedMapSlots, occupiedReduceSlots,
reservedMapSlots, reservedReduceSlots,
totalMapTaskCapacity, totalReduceTaskCapacity,
totalSubmissions,
taskTrackers.size() - getBlacklistedTrackerCount(),
getBlacklistedTrackerCount(), getExcludedNodes().size()) ;
}
public org.apache.hadoop.mapreduce.server.jobtracker.State
getJobTrackerState() {
return getServiceState().equals(ServiceState.LIVE) ?
org.apache.hadoop.mapreduce.server.jobtracker.State.RUNNING
: org.apache.hadoop.mapreduce.server.jobtracker.State.INITIALIZING;
}
public long getTaskTrackerExpiryInterval() {
return tasktrackerExpiryInterval;
}
/**
* Get all active trackers in cluster.
* @return array of TaskTrackerInfo
*/
public TaskTrackerInfo[] getActiveTrackers()
throws IOException, InterruptedException {
List<String> activeTrackers = taskTrackerNames().get(0);
TaskTrackerInfo[] info = new TaskTrackerInfo[activeTrackers.size()];
for (int i = 0; i < activeTrackers.size(); i++) {
info[i] = new TaskTrackerInfo(activeTrackers.get(i));
}
return info;
}
/**
* Get all blacklisted trackers in cluster.
* @return array of TaskTrackerInfo
*/
public TaskTrackerInfo[] getBlacklistedTrackers()
throws IOException, InterruptedException {
Collection<BlackListInfo> blackListed = getBlackListedTrackers();
TaskTrackerInfo[] info = new TaskTrackerInfo[blackListed.size()];
int i = 0;
for (BlackListInfo binfo : blackListed) {
info[i++] = new TaskTrackerInfo(binfo.getTrackerName(),
binfo.getReasonForBlackListing(), binfo.getBlackListReport());
}
return info;
}
public synchronized void killJob(org.apache.hadoop.mapreduce.JobID jobid)
throws IOException {
killJob(JobID.downgrade(jobid));
}
/**
* @deprecated Use {@link #killJob(org.apache.hadoop.mapreduce.JobID)} instead
*/
@Deprecated
public synchronized void killJob(JobID jobid) throws IOException {
if (null == jobid) {
LOG.info("Null jobid object sent to JobTracker.killJob()");
return;
}
JobInProgress job = jobs.get(jobid);
if (null == job) {
LOG.info("killJob(): JobId " + jobid.toString() + " is not a valid job");
return;
}
checkAccess(job, Queue.QueueOperation.ADMINISTER_JOBS);
killJob(job);
}
private synchronized void killJob(JobInProgress job) {
LOG.info("Killing job " + job.getJobID());
JobStatus prevStatus = (JobStatus)job.getStatus().clone();
job.kill();
// Inform the listeners if the job is killed
// Note :
// If the job is killed in the PREP state then the listeners will be
// invoked
// If the job is killed in the RUNNING state then cleanup tasks will be
// launched and the updateTaskStatuses() will take care of it
JobStatus newStatus = (JobStatus)job.getStatus().clone();
if (prevStatus.getRunState() != newStatus.getRunState()
&& newStatus.getRunState() == JobStatus.KILLED) {
JobStatusChangeEvent event =
new JobStatusChangeEvent(job, EventType.RUN_STATE_CHANGED, prevStatus,
newStatus);
updateJobInProgressListeners(event);
}
}
/**
* Initialize a job and inform the listeners about a state change, if any.
* Other components in the framework should use this api to initialize a job.
*/
public void initJob(JobInProgress job) {
if (null == job) {
LOG.info("Init on null job is not valid");
return;
}
try {
JobStatus prevStatus = (JobStatus)job.getStatus().clone();
LOG.info("Initializing " + job.getJobID());
job.initTasks();
// Here the job *should* be in the PREP state.
// From here there are 3 ways :
// - job requires setup : the job remains in PREP state and
// setup is launched to move the job in RUNNING state
// - job is complete (no setup required and no tasks) : complete
// the job and move it to SUCCEEDED
// - job has tasks but doesnt require setup : make the job RUNNING.
if (job.isJobEmpty()) { // is the job empty?
completeEmptyJob(job); // complete it
} else if (!job.isSetupCleanupRequired()) { // setup/cleanup not required
job.completeSetup(); // complete setup and make job running
}
// Inform the listeners if the job state has changed
// Note :
// If job does not require setup, job state will be RUNNING
// If job is configured with 0 maps, 0 reduces and no setup-cleanup then
// the job state will be SUCCEEDED
// otherwise, job state is PREP.
JobStatus newStatus = (JobStatus)job.getStatus().clone();
if (prevStatus.getRunState() != newStatus.getRunState()) {
JobStatusChangeEvent event =
new JobStatusChangeEvent(job, EventType.RUN_STATE_CHANGED, prevStatus,
newStatus);
synchronized (JobTracker.this) {
updateJobInProgressListeners(event);
}
}
} catch (KillInterruptedException kie) {
// If job was killed during initialization, job state will be KILLED
LOG.error("Job initialization interrupted :\n" +
StringUtils.stringifyException(kie));
killJob(job);
} catch (Throwable t) {
// If the job initialization is failed, job state will be FAILED
LOG.error("Job initialization failed:\n" +
StringUtils.stringifyException(t));
failJob(job);
}
}
// This simply marks the job as completed. Note that the caller is responsible
// for raising events.
private synchronized void completeEmptyJob(JobInProgress job) {
job.completeEmptyJob();
}
/**
* Fail a job and inform the listeners. Other components in the framework
* should use this to fail a job.
*/
public synchronized void failJob(JobInProgress job) {
if (null == job) {
LOG.info("Fail on null job is not valid");
return;
}
JobStatus prevStatus = (JobStatus)job.getStatus().clone();
LOG.info("Failing job " + job.getJobID());
job.fail();
// Inform the listeners if the job state has changed
JobStatus newStatus = (JobStatus)job.getStatus().clone();
if (prevStatus.getRunState() != newStatus.getRunState()) {
JobStatusChangeEvent event =
new JobStatusChangeEvent(job, EventType.RUN_STATE_CHANGED, prevStatus,
newStatus);
updateJobInProgressListeners(event);
}
}
/**
* Set the priority of a job
* @param jobid id of the job
* @param priority new priority of the job
*/
public synchronized void setJobPriority(org.apache.hadoop.mapreduce.JobID
jobid, String priority) throws IOException {
setJobPriority(JobID.downgrade(jobid), priority);
}
/**
* Set the priority of a job
* @param jobid id of the job
* @param priority new priority of the job
* @deprecated Use
* {@link #setJobPriority(org.apache.hadoop.mapreduce.JobID, String)} instead
*/
@Deprecated
public synchronized void setJobPriority(JobID jobid,
String priority)
throws IOException {
JobInProgress job = jobs.get(jobid);
if (null == job) {
LOG.info("setJobPriority(): JobId " + jobid.toString()
+ " is not a valid job");
return;
}
checkAccess(job, Queue.QueueOperation.ADMINISTER_JOBS);
JobPriority newPriority = JobPriority.valueOf(priority);
setJobPriority(jobid, newPriority);
}
void storeCompletedJob(JobInProgress job) {
//persists the job info in DFS
completedJobStatusStore.store(job);
}
public JobProfile getJobProfile(org.apache.hadoop.mapreduce.JobID jobid) {
return getJobProfile(JobID.downgrade(jobid));
}
/**
* @deprecated Use {@link #getJobProfile(org.apache.hadoop.mapreduce.JobID)}
* instead
*/
@Deprecated
public JobProfile getJobProfile(JobID jobid) {
synchronized (this) {
JobInProgress job = jobs.get(jobid);
if (job != null) {
return job.getProfile();
}
}
return completedJobStatusStore.readJobProfile(jobid);
}
public JobStatus getJobStatus(org.apache.hadoop.mapreduce.JobID jobid) {
return getJobStatus(JobID.downgrade(jobid));
}
/**
* @deprecated Use
* {@link #getJobStatus(org.apache.hadoop.mapreduce.JobID)} instead
*/
@Deprecated
public JobStatus getJobStatus(JobID jobid) {
if (null == jobid) {
LOG.warn("JobTracker.getJobStatus() cannot get status for null jobid");
return null;
}
synchronized (this) {
JobInProgress job = jobs.get(jobid);
if (job != null) {
return job.getStatus();
} else {
JobStatus status = retireJobs.get(jobid);
if (status != null) {
return status;
}
}
}
return completedJobStatusStore.readJobStatus(jobid);
}
public org.apache.hadoop.mapreduce.Counters getJobCounters(
org.apache.hadoop.mapreduce.JobID jobid) {
Counters counters = getJobCounters(JobID.downgrade(jobid));
if (counters != null) {
return new org.apache.hadoop.mapreduce.Counters(counters);
}
return null;
}
/**
* @deprecated Use
* {@link #getJobCounters(org.apache.hadoop.mapreduce.JobID)} instead
*/
@Deprecated
public Counters getJobCounters(JobID jobid) {
synchronized (this) {
JobInProgress job = jobs.get(jobid);
if (job != null) {
return job.getCounters();
}
}
return completedJobStatusStore.readCounters(jobid);
}
/**
* @param jobid
* @return array of TaskReport
* @deprecated Use
* {@link #getTaskReports(org.apache.hadoop.mapreduce.JobID, TaskType)}
* instead
*/
@Deprecated
public synchronized TaskReport[] getMapTaskReports(JobID jobid) {
JobInProgress job = jobs.get(jobid);
if (job == null) {
return new TaskReport[0];
} else {
Vector<TaskReport> reports = new Vector<TaskReport>();
Vector<TaskInProgress> completeMapTasks =
job.reportTasksInProgress(true, true);
for (Iterator it = completeMapTasks.iterator(); it.hasNext();) {
TaskInProgress tip = (TaskInProgress) it.next();
reports.add(tip.generateSingleReport());
}
Vector<TaskInProgress> incompleteMapTasks =
job.reportTasksInProgress(true, false);
for (Iterator it = incompleteMapTasks.iterator(); it.hasNext();) {
TaskInProgress tip = (TaskInProgress) it.next();
reports.add(tip.generateSingleReport());
}
return reports.toArray(new TaskReport[reports.size()]);
}
}
/**
* @param jobid
* @return array of TaskReport
* @deprecated Use
* {@link #getTaskReports(org.apache.hadoop.mapreduce.JobID, TaskType)}
* instead
*/
@Deprecated
public synchronized TaskReport[] getReduceTaskReports(JobID jobid) {
JobInProgress job = jobs.get(jobid);
if (job == null) {
return new TaskReport[0];
} else {
Vector<TaskReport> reports = new Vector<TaskReport>();
Vector completeReduceTasks = job.reportTasksInProgress(false, true);
for (Iterator it = completeReduceTasks.iterator(); it.hasNext();) {
TaskInProgress tip = (TaskInProgress) it.next();
reports.add(tip.generateSingleReport());
}
Vector incompleteReduceTasks = job.reportTasksInProgress(false, false);
for (Iterator it = incompleteReduceTasks.iterator(); it.hasNext();) {
TaskInProgress tip = (TaskInProgress) it.next();
reports.add(tip.generateSingleReport());
}
return reports.toArray(new TaskReport[reports.size()]);
}
}
/**
* @param jobid
* @return array of TaskReport
* @deprecated Use
* {@link #getTaskReports(org.apache.hadoop.mapreduce.JobID, TaskType)}
* instead
*/
@Deprecated
public synchronized TaskReport[] getCleanupTaskReports(JobID jobid) {
JobInProgress job = jobs.get(jobid);
if (job == null) {
return new TaskReport[0];
} else {
Vector<TaskReport> reports = new Vector<TaskReport>();
Vector<TaskInProgress> completeTasks = job.reportCleanupTIPs(true);
for (Iterator<TaskInProgress> it = completeTasks.iterator();
it.hasNext();) {
TaskInProgress tip = it.next();
reports.add(tip.generateSingleReport());
}
Vector<TaskInProgress> incompleteTasks = job.reportCleanupTIPs(false);
for (Iterator<TaskInProgress> it = incompleteTasks.iterator();
it.hasNext();) {
TaskInProgress tip = it.next();
reports.add(tip.generateSingleReport());
}
return reports.toArray(new TaskReport[reports.size()]);
}
}
/**
* @param jobid
* @return array of TaskReport
* @deprecated Use
* {@link #getTaskReports(org.apache.hadoop.mapreduce.JobID, TaskType)}
* instead
*/
@Deprecated
public synchronized TaskReport[] getSetupTaskReports(JobID jobid) {
JobInProgress job = jobs.get(jobid);
if (job == null) {
return new TaskReport[0];
} else {
Vector<TaskReport> reports = new Vector<TaskReport>();
Vector<TaskInProgress> completeTasks = job.reportSetupTIPs(true);
for (Iterator<TaskInProgress> it = completeTasks.iterator();
it.hasNext();) {
TaskInProgress tip = it.next();
reports.add(tip.generateSingleReport());
}
Vector<TaskInProgress> incompleteTasks = job.reportSetupTIPs(false);
for (Iterator<TaskInProgress> it = incompleteTasks.iterator();
it.hasNext();) {
TaskInProgress tip = it.next();
reports.add(tip.generateSingleReport());
}
return reports.toArray(new TaskReport[reports.size()]);
}
}
public synchronized TaskReport[] getTaskReports(
org.apache.hadoop.mapreduce.JobID jobid, TaskType type) {
switch (type) {
case MAP :
return getMapTaskReports(JobID.downgrade(jobid));
case REDUCE :
return getReduceTaskReports(JobID.downgrade(jobid));
case JOB_CLEANUP:
return getCleanupTaskReports(JobID.downgrade(jobid));
case JOB_SETUP :
return getSetupTaskReports(JobID.downgrade(jobid));
}
return new TaskReport[0];
}
TaskCompletionEvent[] EMPTY_EVENTS = new TaskCompletionEvent[0];
/*
* Returns a list of TaskCompletionEvent for the given job,
* starting from fromEventId.
*/
public synchronized TaskCompletionEvent[] getTaskCompletionEvents(
org.apache.hadoop.mapreduce.JobID jobid, int fromEventId, int maxEvents)
throws IOException {
return getTaskCompletionEvents(JobID.downgrade(jobid),
fromEventId, maxEvents);
}
/*
* Returns a list of TaskCompletionEvent for the given job,
* starting from fromEventId.
* @see org.apache.hadoop.mapred.JobSubmissionProtocol#getTaskCompletionEvents(java.lang.String, int, int)
*/
@Deprecated
public synchronized TaskCompletionEvent[] getTaskCompletionEvents(
JobID jobid, int fromEventId, int maxEvents) throws IOException{
synchronized (this) {
JobInProgress job = this.jobs.get(jobid);
if (null != job) {
if (job.inited()) {
return job.getTaskCompletionEvents(fromEventId, maxEvents);
} else {
return EMPTY_EVENTS;
}
}
}
return completedJobStatusStore.readJobTaskCompletionEvents(jobid, fromEventId, maxEvents);
}
/**
* Get the diagnostics for a given task
* @param taskId the id of the task
* @return an array of the diagnostic messages
*/
public synchronized String[] getTaskDiagnostics(
org.apache.hadoop.mapreduce.TaskAttemptID taskId)
throws IOException {
return getTaskDiagnostics(TaskAttemptID.downgrade(taskId));
}
/**
* Get the diagnostics for a given task
* @param taskId the id of the task
* @return an array of the diagnostic messages
*/
@Deprecated
public synchronized String[] getTaskDiagnostics(TaskAttemptID taskId)
throws IOException {
List<String> taskDiagnosticInfo = null;
JobID jobId = taskId.getJobID();
TaskID tipId = taskId.getTaskID();
JobInProgress job = jobs.get(jobId);
if (job != null) {
TaskInProgress tip = job.getTaskInProgress(tipId);
if (tip != null) {
taskDiagnosticInfo = tip.getDiagnosticInfo(taskId);
}
}
return ((taskDiagnosticInfo == null) ? new String[0]
: taskDiagnosticInfo.toArray(new String[0]));
}
/** Get all the TaskStatuses from the tipid. */
TaskStatus[] getTaskStatuses(TaskID tipid) {
TaskInProgress tip = getTip(tipid);
return (tip == null ? new TaskStatus[0]
: tip.getTaskStatuses());
}
/** Returns the TaskStatus for a particular taskid. */
TaskStatus getTaskStatus(TaskAttemptID taskid) {
TaskInProgress tip = getTip(taskid.getTaskID());
return (tip == null ? null
: tip.getTaskStatus(taskid));
}
/**
* Returns the counters for the specified task in progress.
*/
Counters getTipCounters(TaskID tipid) {
TaskInProgress tip = getTip(tipid);
return (tip == null ? null : tip.getCounters());
}
/**
* Returns the configured task scheduler for this job tracker.
* @return the configured task scheduler
*/
TaskScheduler getTaskScheduler() {
return taskScheduler;
}
/**
* Returns specified TaskInProgress, or null.
*/
public TaskInProgress getTip(TaskID tipid) {
JobInProgress job = jobs.get(tipid.getJobID());
return (job == null ? null : job.getTaskInProgress(tipid));
}
public synchronized boolean killTask(
org.apache.hadoop.mapreduce.TaskAttemptID taskid,
boolean shouldFail) throws IOException {
return killTask(TaskAttemptID.downgrade(taskid), shouldFail);
}
/** Mark a Task to be killed */
@Deprecated
public synchronized boolean killTask(TaskAttemptID taskid, boolean shouldFail) throws IOException{
TaskInProgress tip = taskidToTIPMap.get(taskid);
if(tip != null) {
checkAccess(tip.getJob(), Queue.QueueOperation.ADMINISTER_JOBS);
return tip.killTask(taskid, shouldFail);
}
else {
LOG.info("Kill task attempt failed since task " + taskid + " was not found");
return false;
}
}
/**
* Get tracker name for a given task id.
* @param taskId the name of the task
* @return The name of the task tracker
*/
public synchronized String getAssignedTracker(TaskAttemptID taskId) {
return taskidToTrackerMap.get(taskId);
}
public JobStatus[] jobsToComplete() {
return getJobStatus(jobs.values(), true);
}
public org.apache.hadoop.mapreduce.JobStatus[] getAllJobs() {
List<JobStatus> list = new ArrayList<JobStatus>();
list.addAll(Arrays.asList(getJobStatus(jobs.values(),false)));
list.addAll(retireJobs.getAll());
return list.toArray(new JobStatus[list.size()]);
}
/**
* @see org.apache.hadoop.mapreduce.protocol.ClientProtocol#getSystemDir()
*/
public String getSystemDir() {
if (fs == null) {
throw new java.lang.IllegalStateException("Filesystem is null; "
+ "JobTracker is not live: " + this);
}
Path sysDir = new Path(conf.get(JTConfig.JT_SYSTEM_DIR, "/tmp/hadoop/mapred/system"));
return fs.makeQualified(sysDir).toString();
}
/**
* @see org.apache.hadoop.mapreduce.protocol.ClientProtocol#getStagingAreaDir()
*/
public String getStagingAreaDir() {
Path stagingRootDir = new Path(conf.get(JTConfig.JT_STAGING_AREA_ROOT,
defaultStagingBaseDir));
String user = UserGroupInformation.getCurrentUGI().getUserName();
return fs.makeQualified(new Path(stagingRootDir,
user+"/.staging")).toString();
}
/**
* @see
* org.apache.hadoop.mapreduce.protocol.ClientProtocol#getJobHistoryDir()
*/
public String getJobHistoryDir() {
return jobHistory.getCompletedJobHistoryLocation().toString();
}
///////////////////////////////////////////////////////////////
// JobTracker methods
///////////////////////////////////////////////////////////////
public JobInProgress getJob(JobID jobid) {
return jobs.get(jobid);
}
//Get the job directory in system directory
Path getSystemDirectoryForJob(JobID id) {
return new Path(getSystemDir(), id.toString());
}
//Get the job token file in system directory
Path getSystemFileForJob(JobID id) {
return new Path(getSystemDirectoryForJob(id)+"/" + JOB_INFO_FILE);
}
/**
* Change the run-time priority of the given job.
* @param jobId job id
* @param priority new {@link JobPriority} for the job
*/
synchronized void setJobPriority(JobID jobId, JobPriority priority) {
JobInProgress job = jobs.get(jobId);
if (job != null) {
synchronized (taskScheduler) {
JobStatus oldStatus = (JobStatus)job.getStatus().clone();
job.setPriority(priority);
JobStatus newStatus = (JobStatus)job.getStatus().clone();
JobStatusChangeEvent event =
new JobStatusChangeEvent(job, EventType.PRIORITY_CHANGED, oldStatus,
newStatus);
updateJobInProgressListeners(event);
}
} else {
LOG.warn("Trying to change the priority of an unknown job: " + jobId);
}
}
////////////////////////////////////////////////////
// Methods to track all the TaskTrackers
////////////////////////////////////////////////////
/**
* Accept and process a new TaskTracker profile. We might
* have known about the TaskTracker previously, or it might
* be brand-new. All task-tracker structures have already
* been updated. Just process the contained tasks and any
* jobs that might be affected.
*/
void updateTaskStatuses(TaskTrackerStatus status) {
String trackerName = status.getTrackerName();
for (TaskStatus report : status.getTaskReports()) {
report.setTaskTracker(trackerName);
TaskAttemptID taskId = report.getTaskID();
// expire it
expireLaunchingTasks.removeTask(taskId);
JobInProgress job = getJob(taskId.getJobID());
if (job == null) {
// if job is not there in the cleanup list ... add it
synchronized (trackerToJobsToCleanup) {
Set<JobID> jobs = trackerToJobsToCleanup.get(trackerName);
if (jobs == null) {
jobs = new HashSet<JobID>();
trackerToJobsToCleanup.put(trackerName, jobs);
}
jobs.add(taskId.getJobID());
}
continue;
}
if (!job.inited()) {
// if job is not yet initialized ... kill the attempt
synchronized (trackerToTasksToCleanup) {
Set<TaskAttemptID> tasks = trackerToTasksToCleanup.get(trackerName);
if (tasks == null) {
tasks = new HashSet<TaskAttemptID>();
trackerToTasksToCleanup.put(trackerName, tasks);
}
tasks.add(taskId);
}
continue;
}
TaskInProgress tip = taskidToTIPMap.get(taskId);
if (tip != null) {
// Update the job and inform the listeners if necessary
JobStatus prevStatus = (JobStatus)job.getStatus().clone();
// Clone TaskStatus object here, because JobInProgress
// or TaskInProgress can modify this object and
// the changes should not get reflected in TaskTrackerStatus.
// An old TaskTrackerStatus is used later in countMapTasks, etc.
job.updateTaskStatus(tip, (TaskStatus)report.clone());
JobStatus newStatus = (JobStatus)job.getStatus().clone();
// Update the listeners if an incomplete job completes
if (prevStatus.getRunState() != newStatus.getRunState()) {
JobStatusChangeEvent event =
new JobStatusChangeEvent(job, EventType.RUN_STATE_CHANGED,
prevStatus, newStatus);
updateJobInProgressListeners(event);
}
} else {
LOG.info("Serious problem. While updating status, cannot find taskid "
+ report.getTaskID());
}
// Process 'failed fetch' notifications
List<TaskAttemptID> failedFetchMaps = report.getFetchFailedMaps();
if (failedFetchMaps != null) {
for (TaskAttemptID mapTaskId : failedFetchMaps) {
TaskInProgress failedFetchMap = taskidToTIPMap.get(mapTaskId);
if (failedFetchMap != null) {
// Gather information about the map which has to be failed, if need be
String failedFetchTrackerName = getAssignedTracker(mapTaskId);
if (failedFetchTrackerName == null) {
failedFetchTrackerName = "Lost task tracker";
}
failedFetchMap.getJob().fetchFailureNotification(failedFetchMap,
mapTaskId,
failedFetchTrackerName);
}
}
}
}
}
/**
* We lost the task tracker! All task-tracker structures have
* already been updated. Just process the contained tasks and any
* jobs that might be affected.
*/
void lostTaskTracker(TaskTracker taskTracker) {
String trackerName = taskTracker.getTrackerName();
LOG.info("Lost tracker '" + trackerName + "'");
// remove the tracker from the local structures
synchronized (trackerToJobsToCleanup) {
trackerToJobsToCleanup.remove(trackerName);
}
synchronized (trackerToTasksToCleanup) {
trackerToTasksToCleanup.remove(trackerName);
}
Set<TaskAttemptID> lostTasks = trackerToTaskMap.get(trackerName);
trackerToTaskMap.remove(trackerName);
if (lostTasks != null) {
// List of jobs which had any of their tasks fail on this tracker
Set<JobInProgress> jobsWithFailures = new HashSet<JobInProgress>();
for (TaskAttemptID taskId : lostTasks) {
TaskInProgress tip = taskidToTIPMap.get(taskId);
JobInProgress job = tip.getJob();
// Completed reduce tasks never need to be failed, because
// their outputs go to dfs
// And completed maps with zero reducers of the job
// never need to be failed.
if (!tip.isComplete() ||
(tip.isMapTask() && !tip.isJobSetupTask() &&
job.desiredReduces() != 0)) {
// if the job is done, we don't want to change anything
if (job.getStatus().getRunState() == JobStatus.RUNNING ||
job.getStatus().getRunState() == JobStatus.PREP) {
// the state will be KILLED_UNCLEAN, if the task(map or reduce)
// was RUNNING on the tracker
TaskStatus.State killState = (tip.isRunningTask(taskId) &&
!tip.isJobSetupTask() && !tip.isJobCleanupTask()) ?
TaskStatus.State.KILLED_UNCLEAN : TaskStatus.State.KILLED;
job.failedTask(tip, taskId, ("Lost task tracker: " + trackerName),
(tip.isMapTask() ?
TaskStatus.Phase.MAP :
TaskStatus.Phase.REDUCE),
killState,
trackerName);
jobsWithFailures.add(job);
}
} else {
// Completed 'reduce' task and completed 'maps' with zero
// reducers of the job, not failed;
// only removed from data-structures.
markCompletedTaskAttempt(trackerName, taskId);
}
}
// Penalize this tracker for each of the jobs which
// had any tasks running on it when it was 'lost'
// Also, remove any reserved slots on this tasktracker
for (JobInProgress job : jobsWithFailures) {
job.addTrackerTaskFailure(trackerName, taskTracker);
}
// Cleanup
taskTracker.cancelAllReservations();
// Purge 'marked' tasks, needs to be done
// here to prevent hanging references!
removeMarkedTasks(trackerName);
}
}
/**
* Rereads the config to get hosts and exclude list file names.
* Rereads the files to update the hosts and exclude lists.
*/
public synchronized void refreshNodes() throws IOException {
// check access
PermissionChecker.checkSuperuserPrivilege(mrOwner, supergroup);
// call the actual api
refreshHosts();
}
private synchronized void refreshHosts() throws IOException {
// Reread the config to get HOSTS and HOSTS_EXCLUDE filenames.
// Update the file names and refresh internal includes and excludes list
LOG.info("Refreshing hosts information");
Configuration conf = new Configuration();
hostsReader.updateFileNames(conf.get(JTConfig.JT_HOSTS_FILENAME,""),
conf.get(JTConfig.JT_HOSTS_EXCLUDE_FILENAME, ""));
hostsReader.refresh();
Set<String> excludeSet = new HashSet<String>();
for(Map.Entry<String, TaskTracker> eSet : taskTrackers.entrySet()) {
String trackerName = eSet.getKey();
TaskTrackerStatus status = eSet.getValue().getStatus();
// Check if not include i.e not in host list or in hosts list but excluded
if (!inHostsList(status) || inExcludedHostsList(status)) {
excludeSet.add(status.getHost()); // add to rejected trackers
}
}
decommissionNodes(excludeSet);
}
// main decommission
synchronized void decommissionNodes(Set<String> hosts)
throws IOException {
LOG.info("Decommissioning " + hosts.size() + " nodes");
// create a list of tracker hostnames
synchronized (taskTrackers) {
synchronized (trackerExpiryQueue) {
int trackersDecommissioned = 0;
for (String host : hosts) {
LOG.info("Decommissioning host " + host);
Set<TaskTracker> trackers = hostnameToTaskTracker.remove(host);
if (trackers != null) {
for (TaskTracker tracker : trackers) {
LOG.info("Decommission: Losing tracker "
+ tracker.getTrackerName() + " on host " + host);
removeTracker(tracker);
}
trackersDecommissioned += trackers.size();
}
LOG.info("Host " + host + " is ready for decommissioning");
}
getInstrumentation().setDecommissionedTrackers(trackersDecommissioned);
}
}
}
/**
* Returns a set of excluded nodes.
*/
Collection<String> getExcludedNodes() {
return hostsReader.getExcludedHosts();
}
////////////////////////////////////////////////////////////
// main()
////////////////////////////////////////////////////////////
/**
* Start the JobTracker process. This is used only for debugging. As a rule,
* JobTracker should be run as part of the DFS Namenode process.
*/
public static void main(String argv[]
) throws IOException, InterruptedException {
StringUtils.startupShutdownMessage(JobTracker.class, argv, LOG);
try {
if(argv.length == 0) {
JobTracker tracker = startTracker(new JobConf());
tracker.offerService();
}
else {
if ("-dumpConfiguration".equals(argv[0]) && argv.length == 1) {
dumpConfiguration(new PrintWriter(System.out));
System.out.println();
QueueManager.dumpConfiguration(new PrintWriter(System.out),
new JobConf());
}
else {
System.out.println("usage: JobTracker [-dumpConfiguration]");
System.exit(-1);
}
}
} catch (Throwable e) {
LOG.fatal(StringUtils.stringifyException(e));
System.exit(-1);
}
}
/**
* Dumps the configuration properties in Json format
* @param writer {@link}Writer object to which the output is written
* @throws IOException
*/
private static void dumpConfiguration(Writer writer) throws IOException {
Configuration.dumpConfiguration(new JobConf(), writer);
writer.write("\n");
}
/**
* Gets the root level queues.
*
* @return array of QueueInfo object.
* @throws java.io.IOException
*/
@Override
public QueueInfo[] getRootQueues() throws IOException {
return getQueueInfoArray(queueManager.getRootQueues());
}
/**
* Returns immediate children of queueName.
*
* @param queueName
* @return array of QueueInfo which are children of queueName
* @throws java.io.IOException
*/
@Override
public QueueInfo[] getChildQueues(String queueName) throws IOException {
return getQueueInfoArray(queueManager.getChildQueues(queueName));
}
/**
* Gets the root level queues.
*
* @return array of JobQueueInfo object.
* @throws java.io.IOException
*/
@Deprecated
public JobQueueInfo[] getRootJobQueues() throws IOException {
return queueManager.getRootQueues();
}
@Deprecated
public JobQueueInfo[] getJobQueues() throws IOException {
return queueManager.getJobQueueInfos();
}
@Deprecated
public JobQueueInfo getQueueInfo(String queue) throws IOException {
return queueManager.getJobQueueInfo(queue);
}
private QueueInfo[] getQueueInfoArray(JobQueueInfo[] queues)
throws IOException {
for (JobQueueInfo queue : queues) {
queue.setJobStatuses(getJobsFromQueue(queue.getQueueName()));
}
return queues;
}
@Override
public QueueInfo[] getQueues() throws IOException {
return getQueueInfoArray(queueManager.getJobQueueInfos());
}
@Override
public QueueInfo getQueue(String queue) throws IOException {
JobQueueInfo jqueue = queueManager.getJobQueueInfo(queue);
if (jqueue != null) {
jqueue.setJobStatuses(getJobsFromQueue(jqueue.getQueueName()));
}
return jqueue;
}
public org.apache.hadoop.mapreduce.JobStatus[] getJobsFromQueue(String queue)
throws IOException {
Collection<JobInProgress> jips = null;
if (queueManager.getLeafQueueNames().contains(queue)) {
jips = taskScheduler.getJobs(queue);
}
return getJobStatus(jips,false);
}
@Override
public org.apache.hadoop.mapreduce.QueueAclsInfo[]
getQueueAclsForCurrentUser() throws IOException{
return queueManager.getQueueAcls(
UserGroupInformation.getCurrentUGI());
}
private synchronized JobStatus[] getJobStatus(Collection<JobInProgress> jips,
boolean toComplete) {
if(jips == null || jips.isEmpty()) {
return new JobStatus[]{};
}
ArrayList<JobStatus> jobStatusList = new ArrayList<JobStatus>();
for(JobInProgress jip : jips) {
JobStatus status = jip.getStatus();
status.setStartTime(jip.getStartTime());
status.setUsername(jip.getProfile().getUser());
if(toComplete) {
if(status.getRunState() == JobStatus.RUNNING ||
status.getRunState() == JobStatus.PREP) {
jobStatusList.add(status);
}
}else {
jobStatusList.add(status);
}
}
return jobStatusList.toArray(
new JobStatus[jobStatusList.size()]);
}
/**
* Returns the confgiured maximum number of tasks for a single job
*/
int getMaxTasksPerJob() {
return conf.getInt(JT_TASKS_PER_JOB, -1);
}
@Override
public void refreshServiceAcl() throws IOException {
if (!conf.getBoolean(
ServiceAuthorizationManager.SERVICE_AUTHORIZATION_CONFIG, false)) {
throw new AuthorizationException("Service Level Authorization not enabled!");
}
SecurityUtil.getPolicy().refresh();
}
@Override
public void refreshQueues() throws IOException{
LOG.info("Refreshing queue information. requested by : " +
UserGroupInformation.getCurrentUGI().getUserName());
this.queueManager.refreshQueues(new Configuration(this.conf),
taskScheduler.getQueueRefresher());
}
private void initializeTaskMemoryRelatedConfig() {
memSizeForMapSlotOnJT =
JobConf.normalizeMemoryConfigValue(conf.getLong(
MAPMEMORY_MB,
JobConf.DISABLED_MEMORY_LIMIT));
memSizeForReduceSlotOnJT =
JobConf.normalizeMemoryConfigValue(conf.getLong(
REDUCEMEMORY_MB,
JobConf.DISABLED_MEMORY_LIMIT));
if (conf.get(JobConf.UPPER_LIMIT_ON_TASK_VMEM_PROPERTY) != null) {
LOG.warn(
JobConf.deprecatedString(
JobConf.UPPER_LIMIT_ON_TASK_VMEM_PROPERTY)+
" instead use "+JTConfig.JT_MAX_MAPMEMORY_MB+
" and " + JTConfig.JT_MAX_REDUCEMEMORY_MB
);
limitMaxMemForMapTasks = limitMaxMemForReduceTasks =
JobConf.normalizeMemoryConfigValue(
conf.getLong(
JobConf.UPPER_LIMIT_ON_TASK_VMEM_PROPERTY,
JobConf.DISABLED_MEMORY_LIMIT));
if (limitMaxMemForMapTasks != JobConf.DISABLED_MEMORY_LIMIT &&
limitMaxMemForMapTasks >= 0) {
limitMaxMemForMapTasks = limitMaxMemForReduceTasks =
limitMaxMemForMapTasks /
(1024 * 1024); //Converting old values in bytes to MB
}
} else {
limitMaxMemForMapTasks =
JobConf.normalizeMemoryConfigValue(
conf.getLong(
JTConfig.JT_MAX_MAPMEMORY_MB,
JobConf.DISABLED_MEMORY_LIMIT));
limitMaxMemForReduceTasks =
JobConf.normalizeMemoryConfigValue(
conf.getLong(
JTConfig.JT_MAX_REDUCEMEMORY_MB,
JobConf.DISABLED_MEMORY_LIMIT));
}
LOG.info(new StringBuilder().append("Scheduler configured with ").append(
"(memSizeForMapSlotOnJT, memSizeForReduceSlotOnJT,").append(
" limitMaxMemForMapTasks, limitMaxMemForReduceTasks) (").append(
memSizeForMapSlotOnJT).append(", ").append(memSizeForReduceSlotOnJT)
.append(", ").append(limitMaxMemForMapTasks).append(", ").append(
limitMaxMemForReduceTasks).append(")"));
}
@Override
public void refreshUserToGroupsMappings(Configuration conf) throws IOException {
LOG.info("Refreshing all user-to-groups mappings. Requested by user: " +
UserGroupInformation.getCurrentUGI().getUserName());
SecurityUtil.getUserToGroupsMappingService(conf).refresh();
}
private boolean perTaskMemoryConfigurationSetOnJT() {
if (limitMaxMemForMapTasks == JobConf.DISABLED_MEMORY_LIMIT
|| limitMaxMemForReduceTasks == JobConf.DISABLED_MEMORY_LIMIT
|| memSizeForMapSlotOnJT == JobConf.DISABLED_MEMORY_LIMIT
|| memSizeForReduceSlotOnJT == JobConf.DISABLED_MEMORY_LIMIT) {
return false;
}
return true;
}
/**
* Check the job if it has invalid requirements and throw and IOException if does have.
*
* @param job
* @throws IOException
*/
private void checkMemoryRequirements(JobInProgress job)
throws IOException {
if (!perTaskMemoryConfigurationSetOnJT()) {
LOG.debug("Per-Task memory configuration is not set on JT. "
+ "Not checking the job for invalid memory requirements.");
return;
}
boolean invalidJob = false;
String msg = "";
long maxMemForMapTask = job.getJobConf().getMemoryForMapTask();
long maxMemForReduceTask = job.getJobConf().getMemoryForReduceTask();
if (maxMemForMapTask == JobConf.DISABLED_MEMORY_LIMIT
|| maxMemForReduceTask == JobConf.DISABLED_MEMORY_LIMIT) {
invalidJob = true;
msg = "Invalid job requirements.";
}
if (maxMemForMapTask > limitMaxMemForMapTasks
|| maxMemForReduceTask > limitMaxMemForReduceTasks) {
invalidJob = true;
msg = "Exceeds the cluster's max-memory-limit.";
}
if (invalidJob) {
StringBuilder jobStr =
new StringBuilder().append(job.getJobID().toString()).append("(")
.append(maxMemForMapTask).append(" memForMapTasks ").append(
maxMemForReduceTask).append(" memForReduceTasks): ");
LOG.warn(jobStr.toString() + msg);
throw new IOException(jobStr.toString() + msg);
}
}
synchronized String getFaultReport(String host) {
FaultInfo fi = faultyTrackers.getFaultInfo(host, false);
if (fi == null) {
return "";
}
return fi.getTrackerFaultReport();
}
synchronized Set<ReasonForBlackListing> getReasonForBlackList(String host) {
FaultInfo fi = faultyTrackers.getFaultInfo(host, false);
if (fi == null) {
return new HashSet<ReasonForBlackListing>();
}
return fi.getReasonforblacklisting();
}
synchronized Collection<BlackListInfo> getBlackListedTrackers() {
Collection<BlackListInfo> blackListedTrackers =
new ArrayList<BlackListInfo>();
for(TaskTrackerStatus tracker : blacklistedTaskTrackers()) {
String hostName = tracker.getHost();
BlackListInfo bi = new BlackListInfo();
bi.setTrackerName(tracker.getTrackerName());
Set<ReasonForBlackListing> rfbs =
getReasonForBlackList(hostName);
StringBuffer sb = new StringBuffer();
for(ReasonForBlackListing rfb : rfbs) {
sb.append(rfb.toString());
sb.append(",");
}
if (sb.length() > 0) {
sb.replace(sb.length()-1, sb.length(), "");
}
bi.setReasonForBlackListing(sb.toString());
bi.setBlackListReport(
getFaultReport(hostName));
blackListedTrackers.add(bi);
}
return blackListedTrackers;
}
/** Test method to increment the fault
* This method is synchronized to make sure that the locking order
* "faultyTrackers.potentiallyFaultyTrackers lock followed by taskTrackers
* lock" is under JobTracker lock to avoid deadlocks.
*/
synchronized void incrementFaults(String hostName) {
faultyTrackers.incrementFaults(hostName);
}
JobTracker(JobConf conf, Clock clock, boolean ignoredForSimulation)
throws IOException {
this.clock = clock;
this.conf = conf;
trackerIdentifier = getDateFormat().format(new Date());
if (fs == null) {
fs = FileSystem.get(conf);
}
tasktrackerExpiryInterval =
conf.getLong("mapred.tasktracker.expiry.interval", 10 * 60 * 1000);
retiredJobsCacheSize =
conf.getInt("mapred.job.tracker.retiredjobs.cache.size", 1000);
// min time before retire
MAX_BLACKLISTS_PER_TRACKER =
conf.getInt("mapred.max.tracker.blacklists", 4);
NUM_HEARTBEATS_IN_SECOND =
conf.getInt("mapred.heartbeats.in.second", 100);
try {
mrOwner = UnixUserGroupInformation.login(conf);
} catch (LoginException e) {
throw new IOException(StringUtils.stringifyException(e));
}
supergroup = conf.get("mapred.permissions.supergroup", "supergroup");
this.hostsReader = new HostsFileReader(conf.get("mapred.hosts", ""),
conf.get("mapred.hosts.exclude", ""));
// queue manager
Configuration queuesConf = new Configuration(this.conf);
queueManager = new QueueManager(queuesConf);
// Create the scheduler
Class<? extends TaskScheduler> schedulerClass
= conf.getClass("mapred.jobtracker.taskScheduler",
JobQueueTaskScheduler.class, TaskScheduler.class);
taskScheduler =
(TaskScheduler)ReflectionUtils.newInstance(schedulerClass, conf);
// Set ports, start RPC servers, setup security policy etc.
InetSocketAddress addr = getAddress(conf);
this.localMachine = addr.getHostName();
this.port = addr.getPort();
// Create the jetty server
InetSocketAddress infoSocAddr = NetUtils.createSocketAddr(
conf.get("mapred.job.tracker.http.address", "0.0.0.0:50030"));
String infoBindAddress = infoSocAddr.getHostName();
int tmpInfoPort = infoSocAddr.getPort();
this.startTime = clock.getTime();
infoServer = new HttpServer("job", infoBindAddress, tmpInfoPort,
tmpInfoPort == 0, conf);
infoServer.setAttribute("job.tracker", this);
// initialize history parameters.
String historyLogDir = null;
FileSystem historyFS = null;
jobHistory = new JobHistory();
jobHistory.init(this, conf, this.localMachine, this.startTime);
jobHistory.initDone(conf, fs);
historyLogDir = jobHistory.getCompletedJobHistoryLocation().toString();
infoServer.setAttribute("historyLogDir", historyLogDir);
historyFS = new Path(historyLogDir).getFileSystem(conf);
infoServer.setAttribute("fileSys", historyFS);
infoServer.addServlet("reducegraph", "/taskgraph", TaskGraphServlet.class);
infoServer.start();
this.infoPort = this.infoServer.getPort();
// Initialize instrumentation
JobTrackerInstrumentation tmp;
Class<? extends JobTrackerInstrumentation> metricsInst =
getInstrumentationClass(conf);
try {
java.lang.reflect.Constructor<? extends JobTrackerInstrumentation> c =
metricsInst.getConstructor(new Class[] {JobTracker.class, JobConf.class} );
tmp = c.newInstance(this, conf);
} catch(Exception e) {
//Reflection can throw lots of exceptions -- handle them all by
//falling back on the default.
LOG.error("failed to initialize job tracker metrics", e);
tmp = new JobTrackerMetricsInst(this, conf);
}
myInstrumentation = tmp;
// start the recovery manager
recoveryManager = new RecoveryManager();
this.dnsToSwitchMapping = ReflectionUtils.newInstance(
conf.getClass("topology.node.switch.mapping.impl", ScriptBasedMapping.class,
DNSToSwitchMapping.class), conf);
this.numTaskCacheLevels = conf.getInt("mapred.task.cache.levels",
NetworkTopology.DEFAULT_HOST_LEVEL);
//initializes the job status store
completedJobStatusStore = new CompletedJobStatusStore(conf);
Path homeDir = fs.getHomeDirectory();
defaultStagingBaseDir = homeDir.getParent().toString();
}
/**
* Get the path of the locally stored job file
* @param jobId id of the job
* @return the path of the job file on the local file system
*/
String getLocalJobFilePath(org.apache.hadoop.mapreduce.JobID jobId){
return System.getProperty("hadoop.log.dir") +
File.separator + jobId + "_conf.xml";
}
}