/**
* 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.DataOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.net.InetSocketAddress;
import java.net.URI;
import java.net.URISyntaxException;
import java.security.PrivilegedExceptionAction;
import java.util.ArrayList;
import java.util.Collections;
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.Random;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.TreeMap;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.regex.Pattern;
import javax.crypto.SecretKey;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.DF;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.FileUtil;
import org.apache.hadoop.fs.LocalDirAllocator;
import org.apache.hadoop.fs.LocalFileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.http.HttpServer;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.ipc.RPC;
import org.apache.hadoop.ipc.RemoteException;
import org.apache.hadoop.ipc.Server;
import org.apache.hadoop.mapred.TaskController.DebugScriptContext;
import org.apache.hadoop.mapred.TaskController.JobInitializationContext;
import org.apache.hadoop.mapred.CleanupQueue.PathDeletionContext;
import org.apache.hadoop.mapred.TaskController.TaskControllerPathDeletionContext;
import org.apache.hadoop.mapred.TaskController.TaskControllerTaskPathDeletionContext;
import org.apache.hadoop.mapred.TaskController.TaskControllerJobPathDeletionContext;
import org.apache.hadoop.mapred.TaskTrackerStatus.TaskTrackerHealthStatus;
import org.apache.hadoop.mapred.pipes.Submitter;
import org.apache.hadoop.mapreduce.MRConfig;
import org.apache.hadoop.mapreduce.MRJobConfig;
import org.apache.hadoop.mapreduce.TaskType;
import org.apache.hadoop.mapreduce.filecache.TrackerDistributedCacheManager;
import org.apache.hadoop.mapreduce.security.SecureShuffleUtils;
import org.apache.hadoop.mapreduce.security.TokenCache;
import org.apache.hadoop.security.TokenStorage;
import org.apache.hadoop.mapreduce.security.token.JobTokenIdentifier;
import org.apache.hadoop.mapreduce.security.token.JobTokenSecretManager;
import org.apache.hadoop.mapreduce.server.tasktracker.TTConfig;
import org.apache.hadoop.mapreduce.server.tasktracker.Localizer;
import org.apache.hadoop.mapreduce.task.reduce.ShuffleHeader;
import org.apache.hadoop.metrics.MetricsContext;
import org.apache.hadoop.metrics.MetricsException;
import org.apache.hadoop.metrics.MetricsRecord;
import org.apache.hadoop.metrics.MetricsUtil;
import org.apache.hadoop.metrics.Updater;
import org.apache.hadoop.net.DNS;
import org.apache.hadoop.net.NetUtils;
import org.apache.hadoop.security.UserGroupInformation;
import org.apache.hadoop.security.authorize.PolicyProvider;
import org.apache.hadoop.security.authorize.ServiceAuthorizationManager;
import org.apache.hadoop.util.DiskChecker;
import org.apache.hadoop.mapreduce.util.ConfigUtil;
import org.apache.hadoop.mapreduce.util.MemoryCalculatorPlugin;
import org.apache.hadoop.mapreduce.util.ResourceCalculatorPlugin;
import org.apache.hadoop.mapreduce.util.ProcfsBasedProcessTree;
import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.security.token.TokenIdentifier;
import org.apache.hadoop.util.ReflectionUtils;
import org.apache.hadoop.util.RunJar;
import org.apache.hadoop.util.StringUtils;
import org.apache.hadoop.util.VersionInfo;
import org.apache.hadoop.util.DiskChecker.DiskErrorException;
import org.apache.hadoop.mapreduce.util.MRAsyncDiskService;
/*******************************************************
* TaskTracker is a process that starts and tracks MR Tasks
* in a networked environment. It contacts the JobTracker
* for Task assignments and reporting results.
*
*******************************************************/
@InterfaceAudience.Private
@InterfaceStability.Unstable
public class TaskTracker
implements MRConstants, TaskUmbilicalProtocol, Runnable, TTConfig {
/**
* @deprecated
*/
@Deprecated
static final String MAPRED_TASKTRACKER_VMEM_RESERVED_PROPERTY =
"mapred.tasktracker.vmem.reserved";
/**
* @deprecated
*/
@Deprecated
static final String MAPRED_TASKTRACKER_PMEM_RESERVED_PROPERTY =
"mapred.tasktracker.pmem.reserved";
static final long WAIT_FOR_DONE = 3 * 1000;
private int httpPort;
static enum State {NORMAL, STALE, INTERRUPTED, DENIED}
static{
ConfigUtil.loadResources();
}
public static final Log LOG =
LogFactory.getLog(TaskTracker.class);
public static final String MR_CLIENTTRACE_FORMAT =
"src: %s" + // src IP
", dest: %s" + // dst IP
", maps: %s" + // number of maps
", op: %s" + // operation
", reduceID: %s" + // reduce id
", duration: %s"; // duration
public static final Log ClientTraceLog =
LogFactory.getLog(TaskTracker.class.getName() + ".clienttrace");
volatile boolean running = true;
private LocalDirAllocator localDirAllocator;
String taskTrackerName;
String localHostname;
InetSocketAddress jobTrackAddr;
InetSocketAddress taskReportAddress;
Server taskReportServer = null;
InterTrackerProtocol jobClient;
private TrackerDistributedCacheManager distributedCacheManager;
// last heartbeat response recieved
short heartbeatResponseId = -1;
static final String TASK_CLEANUP_SUFFIX = ".cleanup";
/*
* This is the last 'status' report sent by this tracker to the JobTracker.
*
* If the rpc call succeeds, this 'status' is cleared-out by this tracker;
* indicating that a 'fresh' status report be generated; in the event the
* rpc calls fails for whatever reason, the previous status report is sent
* again.
*/
TaskTrackerStatus status = null;
// The system-directory on HDFS where job files are stored
Path systemDirectory = null;
// The filesystem where job files are stored
FileSystem systemFS = null;
private final HttpServer server;
volatile boolean shuttingDown = false;
Map<TaskAttemptID, TaskInProgress> tasks = new HashMap<TaskAttemptID, TaskInProgress>();
/**
* Map from taskId -> TaskInProgress.
*/
Map<TaskAttemptID, TaskInProgress> runningTasks = null;
Map<JobID, RunningJob> runningJobs = new TreeMap<JobID, RunningJob>();
private final JobTokenSecretManager jobTokenSecretManager
= new JobTokenSecretManager();
volatile int mapTotal = 0;
volatile int reduceTotal = 0;
boolean justStarted = true;
boolean justInited = true;
// Mark reduce tasks that are shuffling to rollback their events index
Set<TaskAttemptID> shouldReset = new HashSet<TaskAttemptID>();
//dir -> DF
Map<String, DF> localDirsDf = new HashMap<String, DF>();
long minSpaceStart = 0;
//must have this much space free to start new tasks
boolean acceptNewTasks = true;
long minSpaceKill = 0;
//if we run under this limit, kill one task
//and make sure we never receive any new jobs
//until all the old tasks have been cleaned up.
//this is if a machine is so full it's only good
//for serving map output to the other nodes
static Random r = new Random();
public static final String SUBDIR = "taskTracker";
static final String DISTCACHEDIR = "distcache";
static final String JOBCACHE = "jobcache";
static final String OUTPUT = "output";
private static final String JARSDIR = "jars";
static final String LOCAL_SPLIT_FILE = "split.dta";
static final String LOCAL_SPLIT_META_FILE = "split.info";
static final String JOBFILE = "job.xml";
static final String JOB_TOKEN_FILE="jobToken"; //localized file
static final String JOB_LOCAL_DIR = MRJobConfig.JOB_LOCAL_DIR;
private JobConf fConf;
private FileSystem localFs;
private Localizer localizer;
private int maxMapSlots;
private int maxReduceSlots;
private int failures;
// MROwner's ugi
private UserGroupInformation mrOwner;
private String supergroup;
// Performance-related config knob to send an out-of-band heartbeat
// on task completion
private volatile boolean oobHeartbeatOnTaskCompletion;
// Track number of completed tasks to send an out-of-band heartbeat
private IntWritable finishedCount = new IntWritable(0);
private MapEventsFetcherThread mapEventsFetcher;
int workerThreads;
CleanupQueue directoryCleanupThread;
private volatile JvmManager jvmManager;
UserLogCleaner taskLogCleanupThread;
private TaskMemoryManagerThread taskMemoryManager;
private boolean taskMemoryManagerEnabled = true;
private long totalVirtualMemoryOnTT = JobConf.DISABLED_MEMORY_LIMIT;
private long totalPhysicalMemoryOnTT = JobConf.DISABLED_MEMORY_LIMIT;
private long mapSlotMemorySizeOnTT = JobConf.DISABLED_MEMORY_LIMIT;
private long reduceSlotSizeMemoryOnTT = JobConf.DISABLED_MEMORY_LIMIT;
private long totalMemoryAllottedForTasks = JobConf.DISABLED_MEMORY_LIMIT;
private long reservedPhysicalMemoryOnTT = JobConf.DISABLED_MEMORY_LIMIT;
private ResourceCalculatorPlugin resourceCalculatorPlugin = null;
// Manages job acls of jobs in TaskTracker
private TaskTrackerJobACLsManager jobACLsManager;
/**
* the minimum interval between jobtracker polls
*/
private volatile int heartbeatInterval = HEARTBEAT_INTERVAL_MIN;
/**
* Number of maptask completion events locations to poll for at one time
*/
private int probe_sample_size = 500;
private IndexCache indexCache;
private MRAsyncDiskService asyncDiskService;
MRAsyncDiskService getAsyncDiskService() {
return asyncDiskService;
}
void setAsyncDiskService(MRAsyncDiskService asyncDiskService) {
this.asyncDiskService = asyncDiskService;
}
/**
* Handle to the specific instance of the {@link TaskController} class
*/
private TaskController taskController;
/**
* Handle to the specific instance of the {@link NodeHealthCheckerService}
*/
private NodeHealthCheckerService healthChecker;
/*
* A list of commitTaskActions for whom commit response has been received
*/
private List<TaskAttemptID> commitResponses =
Collections.synchronizedList(new ArrayList<TaskAttemptID>());
private ShuffleServerMetrics shuffleServerMetrics;
/** This class contains the methods that should be used for metrics-reporting
* the specific metrics for shuffle. The TaskTracker is actually a server for
* the shuffle and hence the name ShuffleServerMetrics.
*/
private class ShuffleServerMetrics implements Updater {
private MetricsRecord shuffleMetricsRecord = null;
private int serverHandlerBusy = 0;
private long outputBytes = 0;
private int failedOutputs = 0;
private int successOutputs = 0;
ShuffleServerMetrics(JobConf conf) {
MetricsContext context = MetricsUtil.getContext("mapred");
shuffleMetricsRecord =
MetricsUtil.createRecord(context, "shuffleOutput");
this.shuffleMetricsRecord.setTag("sessionId", conf.getSessionId());
context.registerUpdater(this);
}
synchronized void serverHandlerBusy() {
++serverHandlerBusy;
}
synchronized void serverHandlerFree() {
--serverHandlerBusy;
}
synchronized void outputBytes(long bytes) {
outputBytes += bytes;
}
synchronized void failedOutput() {
++failedOutputs;
}
synchronized void successOutput() {
++successOutputs;
}
public void doUpdates(MetricsContext unused) {
synchronized (this) {
if (workerThreads != 0) {
shuffleMetricsRecord.setMetric("shuffle_handler_busy_percent",
100*((float)serverHandlerBusy/workerThreads));
} else {
shuffleMetricsRecord.setMetric("shuffle_handler_busy_percent", 0);
}
shuffleMetricsRecord.incrMetric("shuffle_output_bytes",
outputBytes);
shuffleMetricsRecord.incrMetric("shuffle_failed_outputs",
failedOutputs);
shuffleMetricsRecord.incrMetric("shuffle_success_outputs",
successOutputs);
outputBytes = 0;
failedOutputs = 0;
successOutputs = 0;
}
shuffleMetricsRecord.update();
}
}
private TaskTrackerInstrumentation myInstrumentation = null;
public TaskTrackerInstrumentation getTaskTrackerInstrumentation() {
return myInstrumentation;
}
/**
* A list of tips that should be cleaned up.
*/
private BlockingQueue<TaskTrackerAction> tasksToCleanup =
new LinkedBlockingQueue<TaskTrackerAction>();
/**
* A daemon-thread that pulls tips off the list of things to cleanup.
*/
private Thread taskCleanupThread =
new Thread(new Runnable() {
public void run() {
while (true) {
try {
TaskTrackerAction action = tasksToCleanup.take();
if (action instanceof KillJobAction) {
purgeJob((KillJobAction) action);
} else if (action instanceof KillTaskAction) {
processKillTaskAction((KillTaskAction) action);
} else {
LOG.error("Non-delete action given to cleanup thread: "
+ action);
}
} catch (Throwable except) {
LOG.warn(StringUtils.stringifyException(except));
}
}
}
}, "taskCleanup");
void processKillTaskAction(KillTaskAction killAction) throws IOException {
TaskInProgress tip;
synchronized (TaskTracker.this) {
tip = tasks.get(killAction.getTaskID());
}
LOG.info("Received KillTaskAction for task: " +
killAction.getTaskID());
purgeTask(tip, false);
}
public TaskController getTaskController() {
return taskController;
}
// Currently this is used only by tests
void setTaskController(TaskController t) {
taskController = t;
}
private RunningJob addTaskToJob(JobID jobId,
TaskInProgress tip) {
synchronized (runningJobs) {
RunningJob rJob = null;
if (!runningJobs.containsKey(jobId)) {
rJob = new RunningJob(jobId);
rJob.localized = false;
rJob.tasks = new HashSet<TaskInProgress>();
runningJobs.put(jobId, rJob);
} else {
rJob = runningJobs.get(jobId);
}
synchronized (rJob) {
rJob.tasks.add(tip);
}
runningJobs.notify(); //notify the fetcher thread
return rJob;
}
}
private void removeTaskFromJob(JobID jobId, TaskInProgress tip) {
synchronized (runningJobs) {
RunningJob rjob = runningJobs.get(jobId);
if (rjob == null) {
LOG.warn("Unknown job " + jobId + " being deleted.");
} else {
synchronized (rjob) {
rjob.tasks.remove(tip);
}
}
}
}
JobTokenSecretManager getJobTokenSecretManager() {
return jobTokenSecretManager;
}
RunningJob getRunningJob(JobID jobId) {
return runningJobs.get(jobId);
}
Localizer getLocalizer() {
return localizer;
}
void setLocalizer(Localizer l) {
localizer = l;
}
public static String getUserDir(String user) {
return TaskTracker.SUBDIR + Path.SEPARATOR + user;
}
public static String getPrivateDistributedCacheDir(String user) {
return getUserDir(user) + Path.SEPARATOR + TaskTracker.DISTCACHEDIR;
}
public static String getPublicDistributedCacheDir() {
return TaskTracker.SUBDIR + Path.SEPARATOR + TaskTracker.DISTCACHEDIR;
}
public static String getJobCacheSubdir(String user) {
return getUserDir(user) + Path.SEPARATOR + TaskTracker.JOBCACHE;
}
public static String getLocalJobDir(String user, String jobid) {
return getJobCacheSubdir(user) + Path.SEPARATOR + jobid;
}
static String getLocalJobConfFile(String user, String jobid) {
return getLocalJobDir(user, jobid) + Path.SEPARATOR + TaskTracker.JOBFILE;
}
static String getLocalJobTokenFile(String user, String jobid) {
return getLocalJobDir(user, jobid) + Path.SEPARATOR + TaskTracker.JOB_TOKEN_FILE;
}
static String getTaskConfFile(String user, String jobid, String taskid,
boolean isCleanupAttempt) {
return getLocalTaskDir(user, jobid, taskid, isCleanupAttempt)
+ Path.SEPARATOR + TaskTracker.JOBFILE;
}
static String getJobJarsDir(String user, String jobid) {
return getLocalJobDir(user, jobid) + Path.SEPARATOR + TaskTracker.JARSDIR;
}
static String getJobJarFile(String user, String jobid) {
return getJobJarsDir(user, jobid) + Path.SEPARATOR + "job.jar";
}
static String getJobWorkDir(String user, String jobid) {
return getLocalJobDir(user, jobid) + Path.SEPARATOR + MRConstants.WORKDIR;
}
static String getLocalSplitMetaFile(String user, String jobid, String taskid){
return TaskTracker.getLocalTaskDir(user, jobid, taskid) + Path.SEPARATOR
+ TaskTracker.LOCAL_SPLIT_META_FILE;
}
static String getLocalSplitFile(String user, String jobid, String taskid) {
return TaskTracker.getLocalTaskDir(user, jobid, taskid) + Path.SEPARATOR
+ TaskTracker.LOCAL_SPLIT_FILE;
}
static String getIntermediateOutputDir(String user, String jobid,
String taskid) {
return getLocalTaskDir(user, jobid, taskid) + Path.SEPARATOR
+ TaskTracker.OUTPUT;
}
static String getLocalTaskDir(String user, String jobid, String taskid) {
return getLocalTaskDir(user, jobid, taskid, false);
}
public static String getLocalTaskDir(String user, String jobid, String taskid,
boolean isCleanupAttempt) {
String taskDir = getLocalJobDir(user, jobid) + Path.SEPARATOR + taskid;
if (isCleanupAttempt) {
taskDir = taskDir + TASK_CLEANUP_SUFFIX;
}
return taskDir;
}
static String getTaskWorkDir(String user, String jobid, String taskid,
boolean isCleanupAttempt) {
String dir = getLocalTaskDir(user, jobid, taskid, isCleanupAttempt);
return dir + Path.SEPARATOR + MRConstants.WORKDIR;
}
String getPid(TaskAttemptID tid) {
TaskInProgress tip = tasks.get(tid);
if (tip != null) {
return jvmManager.getPid(tip.getTaskRunner());
}
return null;
}
public long getProtocolVersion(String protocol,
long clientVersion) throws IOException {
if (protocol.equals(TaskUmbilicalProtocol.class.getName())) {
return TaskUmbilicalProtocol.versionID;
} else {
throw new IOException("Unknown protocol for task tracker: " +
protocol);
}
}
/**
* Do the real constructor work here. It's in a separate method
* so we can call it again and "recycle" the object after calling
* close().
*/
synchronized void initialize() throws IOException, InterruptedException {
String keytabFilename = fConf.get(TTConfig.TT_KEYTAB_FILE);
UserGroupInformation.setConfiguration(fConf);
if (keytabFilename != null) {
String desiredUser = fConf.get(TTConfig.TT_USER_NAME,
System.getProperty("user.name"));
UserGroupInformation.loginUserFromKeytab(desiredUser,
keytabFilename);
mrOwner = UserGroupInformation.getLoginUser();
} else {
mrOwner = UserGroupInformation.getCurrentUser();
}
supergroup = fConf.get(MRConfig.MR_SUPERGROUP, "supergroup");
LOG.info("Starting tasktracker with owner as " + mrOwner.getShortUserName()
+ " and supergroup as " + supergroup);
localFs = FileSystem.getLocal(fConf);
// use configured nameserver & interface to get local hostname
if (fConf.get(TT_HOST_NAME) != null) {
this.localHostname = fConf.get(TT_HOST_NAME);
}
if (localHostname == null) {
this.localHostname =
DNS.getDefaultHost
(fConf.get(TT_DNS_INTERFACE,"default"),
fConf.get(TT_DNS_NAMESERVER,"default"));
}
// Check local disk, start async disk service, and clean up all
// local directories.
checkLocalDirs(this.fConf.getLocalDirs());
setAsyncDiskService(new MRAsyncDiskService(fConf));
getAsyncDiskService().cleanupAllVolumes();
// Clear out state tables
this.tasks.clear();
this.runningTasks = new LinkedHashMap<TaskAttemptID, TaskInProgress>();
this.runningJobs = new TreeMap<JobID, RunningJob>();
this.mapTotal = 0;
this.reduceTotal = 0;
this.acceptNewTasks = true;
this.status = null;
this.minSpaceStart = this.fConf.getLong(TT_LOCAL_DIR_MINSPACE_START, 0L);
this.minSpaceKill = this.fConf.getLong(TT_LOCAL_DIR_MINSPACE_KILL, 0L);
//tweak the probe sample size (make it a function of numCopiers)
probe_sample_size =
this.fConf.getInt(TT_MAX_TASK_COMPLETION_EVENTS_TO_POLL, 500);
Class<? extends TaskTrackerInstrumentation> metricsInst = getInstrumentationClass(fConf);
try {
java.lang.reflect.Constructor<? extends TaskTrackerInstrumentation> c =
metricsInst.getConstructor(new Class[] {TaskTracker.class} );
this.myInstrumentation = c.newInstance(this);
} catch(Exception e) {
//Reflection can throw lots of exceptions -- handle them all by
//falling back on the default.
LOG.error("failed to initialize taskTracker metrics", e);
this.myInstrumentation = new TaskTrackerMetricsInst(this);
}
// bind address
InetSocketAddress socAddr = NetUtils.createSocketAddr(
fConf.get(TT_REPORT_ADDRESS, "127.0.0.1:0"));
String bindAddress = socAddr.getHostName();
int tmpPort = socAddr.getPort();
this.jvmManager = new JvmManager(this);
// Set service-level authorization security policy
if (this.fConf.getBoolean(
ServiceAuthorizationManager.SERVICE_AUTHORIZATION_CONFIG, false)) {
PolicyProvider policyProvider =
(PolicyProvider)(ReflectionUtils.newInstance(
this.fConf.getClass(PolicyProvider.POLICY_PROVIDER_CONFIG,
MapReducePolicyProvider.class, PolicyProvider.class),
this.fConf));
ServiceAuthorizationManager.refresh(fConf, policyProvider);
}
// RPC initialization
int max = maxMapSlots > maxReduceSlots ?
maxMapSlots : maxReduceSlots;
//set the num handlers to max*2 since canCommit may wait for the duration
//of a heartbeat RPC
this.taskReportServer = RPC.getServer(this.getClass(), this, bindAddress,
tmpPort, 2 * max, false, this.fConf, this.jobTokenSecretManager);
this.taskReportServer.start();
// get the assigned address
this.taskReportAddress = taskReportServer.getListenerAddress();
this.fConf.set(TT_REPORT_ADDRESS,
taskReportAddress.getHostName() + ":" + taskReportAddress.getPort());
LOG.info("TaskTracker up at: " + this.taskReportAddress);
this.taskTrackerName = "tracker_" + localHostname + ":" + taskReportAddress;
LOG.info("Starting tracker " + taskTrackerName);
Class<? extends TaskController> taskControllerClass = fConf.getClass(
TT_TASK_CONTROLLER, DefaultTaskController.class, TaskController.class);
taskController = (TaskController) ReflectionUtils.newInstance(
taskControllerClass, fConf);
// setup and create jobcache directory with appropriate permissions
taskController.setup();
// Initialize DistributedCache
this.distributedCacheManager =
new TrackerDistributedCacheManager(this.fConf, taskController,
asyncDiskService);
this.distributedCacheManager.startCleanupThread();
this.jobClient = (InterTrackerProtocol)
mrOwner.doAs(new PrivilegedExceptionAction<Object>() {
public Object run() throws IOException {
return RPC.waitForProxy(InterTrackerProtocol.class,
InterTrackerProtocol.versionID,
jobTrackAddr, fConf);
}
});
this.justInited = true;
this.running = true;
// start the thread that will fetch map task completion events
this.mapEventsFetcher = new MapEventsFetcherThread();
mapEventsFetcher.setDaemon(true);
mapEventsFetcher.setName(
"Map-events fetcher for all reduce tasks " + "on " +
taskTrackerName);
mapEventsFetcher.start();
Class<? extends ResourceCalculatorPlugin> clazz =
fConf.getClass(TT_RESOURCE_CALCULATOR_PLUGIN,
null, ResourceCalculatorPlugin.class);
resourceCalculatorPlugin = ResourceCalculatorPlugin
.getResourceCalculatorPlugin(clazz, fConf);
LOG.info(" Using ResourceCalculatorPlugin : " + resourceCalculatorPlugin);
initializeMemoryManagement();
setIndexCache(new IndexCache(this.fConf));
//clear old user logs
taskLogCleanupThread.clearOldUserLogs(this.fConf);
mapLauncher = new TaskLauncher(TaskType.MAP, maxMapSlots);
reduceLauncher = new TaskLauncher(TaskType.REDUCE, maxReduceSlots);
mapLauncher.start();
reduceLauncher.start();
// create a localizer instance
setLocalizer(new Localizer(localFs, fConf.getLocalDirs(), taskController));
//Start up node health checker service.
if (shouldStartHealthMonitor(this.fConf)) {
startHealthMonitor(this.fConf);
}
oobHeartbeatOnTaskCompletion =
fConf.getBoolean(TT_OUTOFBAND_HEARBEAT, false);
}
UserGroupInformation getMROwner() {
return mrOwner;
}
String getSuperGroup() {
return supergroup;
}
/**
* Is job level authorization enabled on the TT ?
*/
boolean isJobLevelAuthorizationEnabled() {
return fConf.getBoolean(
MRConfig.JOB_LEVEL_AUTHORIZATION_ENABLING_FLAG, false);
}
public static Class<? extends TaskTrackerInstrumentation> getInstrumentationClass(
Configuration conf) {
return conf.getClass(TT_INSTRUMENTATION,
TaskTrackerMetricsInst.class, TaskTrackerInstrumentation.class);
}
public static void setInstrumentationClass(
Configuration conf, Class<? extends TaskTrackerInstrumentation> t) {
conf.setClass(TT_INSTRUMENTATION,
t, TaskTrackerInstrumentation.class);
}
/**
* Removes all contents of temporary storage. Called upon
* startup, to remove any leftovers from previous run.
*
* Use MRAsyncDiskService.moveAndDeleteAllVolumes instead.
* @see org.apache.hadoop.mapreduce.util.MRAsyncDiskService#cleanupAllVolumes()
*/
@Deprecated
public void cleanupStorage() throws IOException {
this.fConf.deleteLocalFiles();
}
// Object on wait which MapEventsFetcherThread is going to wait.
private Object waitingOn = new Object();
private class MapEventsFetcherThread extends Thread {
private List <FetchStatus> reducesInShuffle() {
List <FetchStatus> fList = new ArrayList<FetchStatus>();
for (Map.Entry <JobID, RunningJob> item : runningJobs.entrySet()) {
RunningJob rjob = item.getValue();
JobID jobId = item.getKey();
FetchStatus f;
synchronized (rjob) {
f = rjob.getFetchStatus();
for (TaskInProgress tip : rjob.tasks) {
Task task = tip.getTask();
if (!task.isMapTask()) {
if (((ReduceTask)task).getPhase() ==
TaskStatus.Phase.SHUFFLE) {
if (rjob.getFetchStatus() == null) {
//this is a new job; we start fetching its map events
f = new FetchStatus(jobId,
((ReduceTask)task).getNumMaps());
rjob.setFetchStatus(f);
}
f = rjob.getFetchStatus();
fList.add(f);
break; //no need to check any more tasks belonging to this
}
}
}
}
}
//at this point, we have information about for which of
//the running jobs do we need to query the jobtracker for map
//outputs (actually map events).
return fList;
}
@Override
public void run() {
LOG.info("Starting thread: " + this.getName());
while (running) {
try {
List <FetchStatus> fList = null;
synchronized (runningJobs) {
while (((fList = reducesInShuffle()).size()) == 0) {
try {
runningJobs.wait();
} catch (InterruptedException e) {
LOG.info("Shutting down: " + this.getName());
return;
}
}
}
// now fetch all the map task events for all the reduce tasks
// possibly belonging to different jobs
boolean fetchAgain = false; //flag signifying whether we want to fetch
//immediately again.
for (FetchStatus f : fList) {
long currentTime = System.currentTimeMillis();
try {
//the method below will return true when we have not
//fetched all available events yet
if (f.fetchMapCompletionEvents(currentTime)) {
fetchAgain = true;
}
} catch (Exception e) {
LOG.warn(
"Ignoring exception that fetch for map completion" +
" events threw for " + f.jobId + " threw: " +
StringUtils.stringifyException(e));
}
if (!running) {
break;
}
}
synchronized (waitingOn) {
try {
if (!fetchAgain) {
waitingOn.wait(heartbeatInterval);
}
} catch (InterruptedException ie) {
LOG.info("Shutting down: " + this.getName());
return;
}
}
} catch (Exception e) {
LOG.info("Ignoring exception " + e.getMessage());
}
}
}
}
private class FetchStatus {
/** The next event ID that we will start querying the JobTracker from*/
private IntWritable fromEventId;
/** This is the cache of map events for a given job */
private List<TaskCompletionEvent> allMapEvents;
/** What jobid this fetchstatus object is for*/
private JobID jobId;
private long lastFetchTime;
private boolean fetchAgain;
public FetchStatus(JobID jobId, int numMaps) {
this.fromEventId = new IntWritable(0);
this.jobId = jobId;
this.allMapEvents = new ArrayList<TaskCompletionEvent>(numMaps);
}
/**
* Reset the events obtained so far.
*/
public void reset() {
// Note that the sync is first on fromEventId and then on allMapEvents
synchronized (fromEventId) {
synchronized (allMapEvents) {
fromEventId.set(0); // set the new index for TCE
allMapEvents.clear();
}
}
}
public TaskCompletionEvent[] getMapEvents(int fromId, int max) {
TaskCompletionEvent[] mapEvents =
TaskCompletionEvent.EMPTY_ARRAY;
boolean notifyFetcher = false;
synchronized (allMapEvents) {
if (allMapEvents.size() > fromId) {
int actualMax = Math.min(max, (allMapEvents.size() - fromId));
List <TaskCompletionEvent> eventSublist =
allMapEvents.subList(fromId, actualMax + fromId);
mapEvents = eventSublist.toArray(mapEvents);
} else {
// Notify Fetcher thread.
notifyFetcher = true;
}
}
if (notifyFetcher) {
synchronized (waitingOn) {
waitingOn.notify();
}
}
return mapEvents;
}
public boolean fetchMapCompletionEvents(long currTime) throws IOException {
if (!fetchAgain && (currTime - lastFetchTime) < heartbeatInterval) {
return false;
}
int currFromEventId = 0;
synchronized (fromEventId) {
currFromEventId = fromEventId.get();
List <TaskCompletionEvent> recentMapEvents =
queryJobTracker(fromEventId, jobId, jobClient);
synchronized (allMapEvents) {
allMapEvents.addAll(recentMapEvents);
}
lastFetchTime = currTime;
if (fromEventId.get() - currFromEventId >= probe_sample_size) {
//return true when we have fetched the full payload, indicating
//that we should fetch again immediately (there might be more to
//fetch
fetchAgain = true;
return true;
}
}
fetchAgain = false;
return false;
}
}
private static LocalDirAllocator lDirAlloc =
new LocalDirAllocator(MRConfig.LOCAL_DIR);
// intialize the job directory
RunningJob localizeJob(TaskInProgress tip
) throws IOException, InterruptedException {
Task t = tip.getTask();
JobID jobId = t.getJobID();
RunningJob rjob = addTaskToJob(jobId, tip);
// Initialize the user directories if needed.
getLocalizer().initializeUserDirs(t.getUser());
synchronized (rjob) {
if (!rjob.localized) {
JobConf localJobConf = localizeJobFiles(t, rjob);
// initialize job log directory
initializeJobLogDir(jobId);
// Now initialize the job via task-controller so as to set
// ownership/permissions of jars, job-work-dir. Note that initializeJob
// should be the last call after every other directory/file to be
// directly under the job directory is created.
JobInitializationContext context = new JobInitializationContext();
context.jobid = jobId;
context.user = t.getUser();
context.workDir = new File(localJobConf.get(JOB_LOCAL_DIR));
taskController.initializeJob(context);
rjob.jobConf = localJobConf;
rjob.keepJobFiles = ((localJobConf.getKeepTaskFilesPattern() != null) ||
localJobConf.getKeepFailedTaskFiles());
rjob.localized = true;
}
}
return rjob;
}
private FileSystem getFS(final Path filePath, JobID jobId,
final Configuration conf) throws IOException, InterruptedException {
RunningJob rJob = runningJobs.get(jobId);
FileSystem userFs =
rJob.ugi.doAs(new PrivilegedExceptionAction<FileSystem>() {
public FileSystem run() throws IOException {
return filePath.getFileSystem(conf);
}});
return userFs;
}
/**
* Localize the job on this tasktracker. Specifically
* <ul>
* <li>Cleanup and create job directories on all disks</li>
* <li>Download the job config file job.xml from the FS</li>
* <li>Create the job work directory and set {@link TaskTracker#JOB_LOCAL_DIR}
* in the configuration.
* <li>Download the job jar file job.jar from the FS, unjar it and set jar
* file in the configuration.</li>
* </ul>
*
* @param t task whose job has to be localized on this TT
* @return the modified job configuration to be used for all the tasks of this
* job as a starting point.
* @throws IOException
*/
JobConf localizeJobFiles(Task t, RunningJob rjob)
throws IOException, InterruptedException {
JobID jobId = t.getJobID();
String userName = t.getUser();
// Initialize the job directories
FileSystem localFs = FileSystem.getLocal(fConf);
getLocalizer().initializeJobDirs(userName, jobId);
// save local copy of JobToken file
String localJobTokenFile = localizeJobTokenFile(t.getUser(), jobId);
rjob.ugi = UserGroupInformation.createRemoteUser(t.getUser());
TokenStorage ts = TokenCache.loadTokens(localJobTokenFile, fConf);
Token<JobTokenIdentifier> jt = TokenCache.getJobToken(ts);
if (jt != null) { //could be null in the case of some unit tests
getJobTokenSecretManager().addTokenForJob(jobId.toString(), jt);
}
for (Token<? extends TokenIdentifier> token : ts.getAllTokens()) {
rjob.ugi.addToken(token);
}
// Download the job.xml for this job from the system FS
Path localJobFile =
localizeJobConfFile(new Path(t.getJobFile()), userName, jobId);
JobConf localJobConf = new JobConf(localJobFile);
//WE WILL TRUST THE USERNAME THAT WE GOT FROM THE JOBTRACKER
//AS PART OF THE TASK OBJECT
localJobConf.setUser(userName);
// set the location of the token file into jobConf to transfer
// the name to TaskRunner
localJobConf.set(TokenCache.JOB_TOKENS_FILENAME,
localJobTokenFile.toString());
// create the 'job-work' directory: job-specific shared directory for use as
// scratch space by all tasks of the same job running on this TaskTracker.
Path workDir =
lDirAlloc.getLocalPathForWrite(getJobWorkDir(userName, jobId
.toString()), fConf);
if (!localFs.mkdirs(workDir)) {
throw new IOException("Mkdirs failed to create "
+ workDir.toString());
}
System.setProperty(JOB_LOCAL_DIR, workDir.toUri().getPath());
localJobConf.set(JOB_LOCAL_DIR, workDir.toUri().getPath());
// Download the job.jar for this job from the system FS
localizeJobJarFile(userName, jobId, localFs, localJobConf);
return localJobConf;
}
// create job userlog dir
void initializeJobLogDir(JobID jobId) {
// remove it from tasklog cleanup thread first,
// it might be added there because of tasktracker reinit or restart
taskLogCleanupThread.unmarkJobFromLogDeletion(jobId);
localizer.initializeJobLogDir(jobId);
}
/**
* Download the job configuration file from the FS.
*
* @param t Task whose job file has to be downloaded
* @param jobId jobid of the task
* @return the local file system path of the downloaded file.
* @throws IOException
*/
private Path localizeJobConfFile(Path jobFile, String user, JobID jobId)
throws IOException, InterruptedException {
final JobConf conf = new JobConf(getJobConf());
FileSystem userFs = getFS(jobFile, jobId, conf);
// Get sizes of JobFile
// sizes are -1 if they are not present.
FileStatus status = null;
long jobFileSize = -1;
try {
status = userFs.getFileStatus(jobFile);
jobFileSize = status.getLen();
} catch(FileNotFoundException fe) {
jobFileSize = -1;
}
Path localJobFile =
lDirAlloc.getLocalPathForWrite(getLocalJobConfFile(user, jobId.toString()),
jobFileSize, fConf);
// Download job.xml
userFs.copyToLocalFile(jobFile, localJobFile);
return localJobFile;
}
/**
* Download the job jar file from FS to the local file system and unjar it.
* Set the local jar file in the passed configuration.
*
* @param jobId
* @param localFs
* @param localJobConf
* @throws IOException
*/
private void localizeJobJarFile(String user, JobID jobId, FileSystem localFs,
JobConf localJobConf)
throws IOException, InterruptedException {
// copy Jar file to the local FS and unjar it.
String jarFile = localJobConf.getJar();
FileStatus status = null;
long jarFileSize = -1;
if (jarFile != null) {
Path jarFilePath = new Path(jarFile);
FileSystem fs = getFS(jarFilePath, jobId, localJobConf);
try {
status = fs.getFileStatus(jarFilePath);
jarFileSize = status.getLen();
} catch (FileNotFoundException fe) {
jarFileSize = -1;
}
// Here we check for five times the size of jarFileSize to accommodate for
// unjarring the jar file in the jars directory
Path localJarFile =
lDirAlloc.getLocalPathForWrite(
getJobJarFile(user, jobId.toString()), 5 * jarFileSize, fConf);
// Download job.jar
fs.copyToLocalFile(jarFilePath, localJarFile);
localJobConf.setJar(localJarFile.toString());
// Un-jar the parts of the job.jar that need to be added to the classpath
RunJar.unJar(
new File(localJarFile.toString()),
new File(localJarFile.getParent().toString()),
localJobConf.getJarUnpackPattern());
}
}
private void launchTaskForJob(TaskInProgress tip, JobConf jobConf) throws IOException{
synchronized (tip) {
tip.setJobConf(jobConf);
tip.launchTask();
}
}
public synchronized void shutdown() throws IOException {
shuttingDown = true;
close();
if (this.server != null) {
try {
LOG.info("Shutting down StatusHttpServer");
this.server.stop();
} catch (Exception e) {
LOG.warn("Exception shutting down TaskTracker", e);
}
}
}
/**
* Close down the TaskTracker and all its components. We must also shutdown
* any running tasks or threads, and cleanup disk space. A new TaskTracker
* within the same process space might be restarted, so everything must be
* clean.
*/
public synchronized void close() throws IOException {
//
// Kill running tasks. Do this in a 2nd vector, called 'tasksToClose',
// because calling jobHasFinished() may result in an edit to 'tasks'.
//
TreeMap<TaskAttemptID, TaskInProgress> tasksToClose =
new TreeMap<TaskAttemptID, TaskInProgress>();
tasksToClose.putAll(tasks);
for (TaskInProgress tip : tasksToClose.values()) {
tip.jobHasFinished(false);
}
this.running = false;
if (asyncDiskService != null) {
// Clear local storage
asyncDiskService.cleanupAllVolumes();
// Shutdown all async deletion threads with up to 10 seconds of delay
asyncDiskService.shutdown();
try {
if (!asyncDiskService.awaitTermination(10000)) {
asyncDiskService.shutdownNow();
asyncDiskService = null;
}
} catch (InterruptedException e) {
asyncDiskService.shutdownNow();
asyncDiskService = null;
}
}
// Shutdown the fetcher thread
this.mapEventsFetcher.interrupt();
//stop the launchers
this.mapLauncher.interrupt();
this.reduceLauncher.interrupt();
this.distributedCacheManager.stopCleanupThread();
jvmManager.stop();
// shutdown RPC connections
RPC.stopProxy(jobClient);
// wait for the fetcher thread to exit
for (boolean done = false; !done; ) {
try {
this.mapEventsFetcher.join();
done = true;
} catch (InterruptedException e) {
}
}
if (taskReportServer != null) {
taskReportServer.stop();
taskReportServer = null;
}
if (healthChecker != null) {
//stop node health checker service
healthChecker.stop();
healthChecker = null;
}
}
/**
* For testing
*/
TaskTracker() {
server = null;
}
void setConf(JobConf conf) {
fConf = conf;
}
/**
* Start with the local machine name, and the default JobTracker
*/
public TaskTracker(JobConf conf) throws IOException, InterruptedException {
fConf = conf;
maxMapSlots = conf.getInt(TT_MAP_SLOTS, 2);
maxReduceSlots = conf.getInt(TT_REDUCE_SLOTS, 2);
this.jobTrackAddr = JobTracker.getAddress(conf);
InetSocketAddress infoSocAddr = NetUtils.createSocketAddr(
conf.get(TT_HTTP_ADDRESS, "0.0.0.0:50060"));
String httpBindAddress = infoSocAddr.getHostName();
int httpPort = infoSocAddr.getPort();
this.server = new HttpServer("task", httpBindAddress, httpPort,
httpPort == 0, conf);
workerThreads = conf.getInt(TT_HTTP_THREADS, 40);
this.shuffleServerMetrics = new ShuffleServerMetrics(conf);
server.setThreads(1, workerThreads);
// let the jsp pages get to the task tracker, config, and other relevant
// objects
FileSystem local = FileSystem.getLocal(conf);
this.localDirAllocator = new LocalDirAllocator(MRConfig.LOCAL_DIR);
server.setAttribute("task.tracker", this);
server.setAttribute("local.file.system", local);
server.setAttribute("conf", conf);
server.setAttribute("log", LOG);
server.setAttribute("localDirAllocator", localDirAllocator);
server.setAttribute("shuffleServerMetrics", shuffleServerMetrics);
server.addInternalServlet("mapOutput", "/mapOutput", MapOutputServlet.class);
server.addServlet("taskLog", "/tasklog", TaskLogServlet.class);
server.start();
this.httpPort = server.getPort();
checkJettyPort(httpPort);
// create task log cleanup thread
setTaskLogCleanupThread(new UserLogCleaner(fConf));
// Initialize the jobACLSManager
jobACLsManager = new TaskTrackerJobACLsManager(this);
initialize();
}
private void checkJettyPort(int port) throws IOException {
//See HADOOP-4744
if (port < 0) {
shuttingDown = true;
throw new IOException("Jetty problem. Jetty didn't bind to a " +
"valid port");
}
}
private void startCleanupThreads() throws IOException {
taskCleanupThread.setDaemon(true);
taskCleanupThread.start();
directoryCleanupThread = new CleanupQueue();
// start tasklog cleanup thread
taskLogCleanupThread.setDaemon(true);
taskLogCleanupThread.start();
}
// only used by tests
void setCleanupThread(CleanupQueue c) {
directoryCleanupThread = c;
}
CleanupQueue getCleanupThread() {
return directoryCleanupThread;
}
UserLogCleaner getTaskLogCleanupThread() {
return this.taskLogCleanupThread;
}
void setTaskLogCleanupThread(UserLogCleaner t) {
this.taskLogCleanupThread = t;
}
void setIndexCache(IndexCache cache) {
this.indexCache = cache;
}
/**
* The connection to the JobTracker, used by the TaskRunner
* for locating remote files.
*/
public InterTrackerProtocol getJobClient() {
return jobClient;
}
/** Return the port at which the tasktracker bound to */
public synchronized InetSocketAddress getTaskTrackerReportAddress() {
return taskReportAddress;
}
/** Queries the job tracker for a set of outputs ready to be copied
* @param fromEventId the first event ID we want to start from, this is
* modified by the call to this method
* @param jobClient the job tracker
* @return a set of locations to copy outputs from
* @throws IOException
*/
private List<TaskCompletionEvent> queryJobTracker(IntWritable fromEventId,
JobID jobId,
InterTrackerProtocol jobClient)
throws IOException {
TaskCompletionEvent t[] = jobClient.getTaskCompletionEvents(
jobId,
fromEventId.get(),
probe_sample_size);
//we are interested in map task completion events only. So store
//only those
List <TaskCompletionEvent> recentMapEvents =
new ArrayList<TaskCompletionEvent>();
for (int i = 0; i < t.length; i++) {
if (t[i].isMapTask()) {
recentMapEvents.add(t[i]);
}
}
fromEventId.set(fromEventId.get() + t.length);
return recentMapEvents;
}
/**
* Main service loop. Will stay in this loop forever.
*/
State offerService() throws Exception {
long lastHeartbeat = 0;
while (running && !shuttingDown) {
try {
long now = System.currentTimeMillis();
long waitTime = heartbeatInterval - (now - lastHeartbeat);
if (waitTime > 0) {
// sleeps for the wait time or
// until there are empty slots to schedule tasks
synchronized (finishedCount) {
if (finishedCount.get() == 0) {
finishedCount.wait(waitTime);
}
finishedCount.set(0);
}
}
// If the TaskTracker is just starting up:
// 1. Verify the buildVersion
// 2. Get the system directory & filesystem
if(justInited) {
String jobTrackerBV = jobClient.getBuildVersion();
if(!VersionInfo.getBuildVersion().equals(jobTrackerBV)) {
String msg = "Shutting down. Incompatible buildVersion." +
"\nJobTracker's: " + jobTrackerBV +
"\nTaskTracker's: "+ VersionInfo.getBuildVersion();
LOG.error(msg);
try {
jobClient.reportTaskTrackerError(taskTrackerName, null, msg);
} catch(Exception e ) {
LOG.info("Problem reporting to jobtracker: " + e);
}
return State.DENIED;
}
String dir = jobClient.getSystemDir();
if (dir == null) {
throw new IOException("Failed to get system directory");
}
systemDirectory = new Path(dir);
systemFS = systemDirectory.getFileSystem(fConf);
}
// Send the heartbeat and process the jobtracker's directives
HeartbeatResponse heartbeatResponse = transmitHeartBeat(now);
// Note the time when the heartbeat returned, use this to decide when to send the
// next heartbeat
lastHeartbeat = System.currentTimeMillis();
TaskTrackerAction[] actions = heartbeatResponse.getActions();
if(LOG.isDebugEnabled()) {
LOG.debug("Got heartbeatResponse from JobTracker with responseId: " +
heartbeatResponse.getResponseId() + " and " +
((actions != null) ? actions.length : 0) + " actions");
}
if (reinitTaskTracker(actions)) {
return State.STALE;
}
// resetting heartbeat interval from the response.
heartbeatInterval = heartbeatResponse.getHeartbeatInterval();
justStarted = false;
justInited = false;
if (actions != null){
for(TaskTrackerAction action: actions) {
if (action instanceof LaunchTaskAction) {
addToTaskQueue((LaunchTaskAction)action);
} else if (action instanceof CommitTaskAction) {
CommitTaskAction commitAction = (CommitTaskAction)action;
if (!commitResponses.contains(commitAction.getTaskID())) {
LOG.info("Received commit task action for " +
commitAction.getTaskID());
commitResponses.add(commitAction.getTaskID());
}
} else {
tasksToCleanup.put(action);
}
}
}
markUnresponsiveTasks();
killOverflowingTasks();
//we've cleaned up, resume normal operation
if (!acceptNewTasks && isIdle()) {
acceptNewTasks=true;
}
//The check below may not be required every iteration but we are
//erring on the side of caution here. We have seen many cases where
//the call to jetty's getLocalPort() returns different values at
//different times. Being a real paranoid here.
checkJettyPort(server.getPort());
} catch (InterruptedException ie) {
LOG.info("Interrupted. Closing down.");
return State.INTERRUPTED;
} catch (DiskErrorException de) {
String msg = "Exiting task tracker for disk error:\n" +
StringUtils.stringifyException(de);
LOG.error(msg);
synchronized (this) {
jobClient.reportTaskTrackerError(taskTrackerName,
"DiskErrorException", msg);
}
return State.STALE;
} catch (RemoteException re) {
String reClass = re.getClassName();
if (DisallowedTaskTrackerException.class.getName().equals(reClass)) {
LOG.info("Tasktracker disallowed by JobTracker.");
return State.DENIED;
}
} catch (Exception except) {
String msg = "Caught exception: " +
StringUtils.stringifyException(except);
LOG.error(msg);
}
}
return State.NORMAL;
}
private long previousUpdate = 0;
/**
* Build and transmit the heart beat to the JobTracker
* @param now current time
* @return false if the tracker was unknown
* @throws IOException
*/
HeartbeatResponse transmitHeartBeat(long now) throws IOException {
// Send Counters in the status once every COUNTER_UPDATE_INTERVAL
boolean sendCounters;
if (now > (previousUpdate + COUNTER_UPDATE_INTERVAL)) {
sendCounters = true;
previousUpdate = now;
}
else {
sendCounters = false;
}
//
// Check if the last heartbeat got through...
// if so then build the heartbeat information for the JobTracker;
// else resend the previous status information.
//
if (status == null) {
synchronized (this) {
status = new TaskTrackerStatus(taskTrackerName, localHostname,
httpPort,
cloneAndResetRunningTaskStatuses(
sendCounters),
failures,
maxMapSlots,
maxReduceSlots);
}
} else {
LOG.info("Resending 'status' to '" + jobTrackAddr.getHostName() +
"' with reponseId '" + heartbeatResponseId);
}
//
// Check if we should ask for a new Task
//
boolean askForNewTask;
long localMinSpaceStart;
synchronized (this) {
askForNewTask =
((status.countOccupiedMapSlots() < maxMapSlots ||
status.countOccupiedReduceSlots() < maxReduceSlots) &&
acceptNewTasks);
localMinSpaceStart = minSpaceStart;
}
if (askForNewTask) {
checkLocalDirs(fConf.getLocalDirs());
askForNewTask = enoughFreeSpace(localMinSpaceStart);
long freeDiskSpace = getFreeSpace();
long totVmem = getTotalVirtualMemoryOnTT();
long totPmem = getTotalPhysicalMemoryOnTT();
long availableVmem = getAvailableVirtualMemoryOnTT();
long availablePmem = getAvailablePhysicalMemoryOnTT();
long cumuCpuTime = getCumulativeCpuTimeOnTT();
long cpuFreq = getCpuFrequencyOnTT();
int numCpu = getNumProcessorsOnTT();
float cpuUsage = getCpuUsageOnTT();
status.getResourceStatus().setAvailableSpace(freeDiskSpace);
status.getResourceStatus().setTotalVirtualMemory(totVmem);
status.getResourceStatus().setTotalPhysicalMemory(totPmem);
status.getResourceStatus().setMapSlotMemorySizeOnTT(
mapSlotMemorySizeOnTT);
status.getResourceStatus().setReduceSlotMemorySizeOnTT(
reduceSlotSizeMemoryOnTT);
status.getResourceStatus().setAvailableVirtualMemory(availableVmem);
status.getResourceStatus().setAvailablePhysicalMemory(availablePmem);
status.getResourceStatus().setCumulativeCpuTime(cumuCpuTime);
status.getResourceStatus().setCpuFrequency(cpuFreq);
status.getResourceStatus().setNumProcessors(numCpu);
status.getResourceStatus().setCpuUsage(cpuUsage);
}
//add node health information
TaskTrackerHealthStatus healthStatus = status.getHealthStatus();
synchronized (this) {
if (healthChecker != null) {
healthChecker.setHealthStatus(healthStatus);
} else {
healthStatus.setNodeHealthy(true);
healthStatus.setLastReported(0L);
healthStatus.setHealthReport("");
}
}
//
// Xmit the heartbeat
//
HeartbeatResponse heartbeatResponse = jobClient.heartbeat(status,
justStarted,
justInited,
askForNewTask,
heartbeatResponseId);
//
// The heartbeat got through successfully!
//
heartbeatResponseId = heartbeatResponse.getResponseId();
synchronized (this) {
for (TaskStatus taskStatus : status.getTaskReports()) {
if (taskStatus.getRunState() != TaskStatus.State.RUNNING &&
taskStatus.getRunState() != TaskStatus.State.UNASSIGNED &&
taskStatus.getRunState() != TaskStatus.State.COMMIT_PENDING &&
!taskStatus.inTaskCleanupPhase()) {
if (taskStatus.getIsMap()) {
mapTotal--;
} else {
reduceTotal--;
}
try {
myInstrumentation.completeTask(taskStatus.getTaskID());
} catch (MetricsException me) {
LOG.warn("Caught: " + StringUtils.stringifyException(me));
}
runningTasks.remove(taskStatus.getTaskID());
}
}
// Clear transient status information which should only
// be sent once to the JobTracker
for (TaskInProgress tip: runningTasks.values()) {
tip.getStatus().clearStatus();
}
}
// Force a rebuild of 'status' on the next iteration
status = null;
return heartbeatResponse;
}
/**
* Return the total virtual memory available on this TaskTracker.
* @return total size of virtual memory.
*/
long getTotalVirtualMemoryOnTT() {
return totalVirtualMemoryOnTT;
}
/**
* Return the total physical memory available on this TaskTracker.
* @return total size of physical memory.
*/
long getTotalPhysicalMemoryOnTT() {
return totalPhysicalMemoryOnTT;
}
/**
* Return the free virtual memory available on this TaskTracker.
* @return total size of free virtual memory.
*/
long getAvailableVirtualMemoryOnTT() {
long availableVirtualMemoryOnTT = TaskTrackerStatus.UNAVAILABLE;
if (resourceCalculatorPlugin != null) {
availableVirtualMemoryOnTT =
resourceCalculatorPlugin.getAvailableVirtualMemorySize();
}
return availableVirtualMemoryOnTT;
}
/**
* Return the free physical memory available on this TaskTracker.
* @return total size of free physical memory in bytes
*/
long getAvailablePhysicalMemoryOnTT() {
long availablePhysicalMemoryOnTT = TaskTrackerStatus.UNAVAILABLE;
if (resourceCalculatorPlugin != null) {
availablePhysicalMemoryOnTT =
resourceCalculatorPlugin.getAvailablePhysicalMemorySize();
}
return availablePhysicalMemoryOnTT;
}
/**
* Return the cumulative CPU used time on this TaskTracker since system is on
* @return cumulative CPU used time in millisecond
*/
long getCumulativeCpuTimeOnTT() {
long cumulativeCpuTime = TaskTrackerStatus.UNAVAILABLE;
if (resourceCalculatorPlugin != null) {
cumulativeCpuTime = resourceCalculatorPlugin.getCumulativeCpuTime();
}
return cumulativeCpuTime;
}
/**
* Return the number of Processors on this TaskTracker
* @return number of processors
*/
int getNumProcessorsOnTT() {
int numProcessors = TaskTrackerStatus.UNAVAILABLE;
if (resourceCalculatorPlugin != null) {
numProcessors = resourceCalculatorPlugin.getNumProcessors();
}
return numProcessors;
}
/**
* Return the CPU frequency of this TaskTracker
* @return CPU frequency in kHz
*/
long getCpuFrequencyOnTT() {
long cpuFrequency = TaskTrackerStatus.UNAVAILABLE;
if (resourceCalculatorPlugin != null) {
cpuFrequency = resourceCalculatorPlugin.getCpuFrequency();
}
return cpuFrequency;
}
/**
* Return the CPU usage in % of this TaskTracker
* @return CPU usage in %
*/
float getCpuUsageOnTT() {
float cpuUsage = TaskTrackerStatus.UNAVAILABLE;
if (resourceCalculatorPlugin != null) {
cpuUsage = resourceCalculatorPlugin.getCpuUsage();
}
return cpuUsage;
}
long getTotalMemoryAllottedForTasksOnTT() {
return totalMemoryAllottedForTasks;
}
/**
* @return The amount of physical memory that will not be used for running
* tasks in bytes. Returns JobConf.DISABLED_MEMORY_LIMIT if it is not
* configured.
*/
long getReservedPhysicalMemoryOnTT() {
return reservedPhysicalMemoryOnTT;
}
/**
* Check if the jobtracker directed a 'reset' of the tasktracker.
*
* @param actions the directives of the jobtracker for the tasktracker.
* @return <code>true</code> if tasktracker is to be reset,
* <code>false</code> otherwise.
*/
private boolean reinitTaskTracker(TaskTrackerAction[] actions) {
if (actions != null) {
for (TaskTrackerAction action : actions) {
if (action.getActionId() ==
TaskTrackerAction.ActionType.REINIT_TRACKER) {
LOG.info("Recieved RenitTrackerAction from JobTracker");
return true;
}
}
}
return false;
}
/**
* Kill any tasks that have not reported progress in the last X seconds.
*/
private synchronized void markUnresponsiveTasks() throws IOException {
long now = System.currentTimeMillis();
for (TaskInProgress tip: runningTasks.values()) {
if (tip.getRunState() == TaskStatus.State.RUNNING ||
tip.getRunState() == TaskStatus.State.COMMIT_PENDING ||
tip.isCleaningup()) {
// Check the per-job timeout interval for tasks;
// an interval of '0' implies it is never timed-out
long jobTaskTimeout = tip.getTaskTimeout();
if (jobTaskTimeout == 0) {
continue;
}
// Check if the task has not reported progress for a
// time-period greater than the configured time-out
long timeSinceLastReport = now - tip.getLastProgressReport();
if (timeSinceLastReport > jobTaskTimeout && !tip.wasKilled) {
String msg =
"Task " + tip.getTask().getTaskID() + " failed to report status for "
+ (timeSinceLastReport / 1000) + " seconds. Killing!";
LOG.info(tip.getTask().getTaskID() + ": " + msg);
ReflectionUtils.logThreadInfo(LOG, "lost task", 30);
tip.reportDiagnosticInfo(msg);
myInstrumentation.timedoutTask(tip.getTask().getTaskID());
dumpTaskStack(tip);
purgeTask(tip, true);
}
}
}
}
/**
* Builds list of PathDeletionContext objects for the given paths
*/
private static PathDeletionContext[] buildPathDeletionContexts(FileSystem fs,
Path[] paths) {
int i = 0;
PathDeletionContext[] contexts = new PathDeletionContext[paths.length];
for (Path p : paths) {
contexts[i++] = new PathDeletionContext(fs, p.toUri().getPath());
}
return contexts;
}
/**
* Builds list of {@link TaskControllerJobPathDeletionContext} objects for a
* job each pointing to the job's jobLocalDir.
* @param fs : FileSystem in which the dirs to be deleted
* @param paths : mapred-local-dirs
* @param id : {@link JobID} of the job for which the local-dir needs to
* be cleaned up.
* @param user : Job owner's username
* @param taskController : the task-controller to be used for deletion of
* jobLocalDir
*/
static PathDeletionContext[] buildTaskControllerJobPathDeletionContexts(
FileSystem fs, Path[] paths, JobID id, String user,
TaskController taskController)
throws IOException {
int i = 0;
PathDeletionContext[] contexts =
new TaskControllerPathDeletionContext[paths.length];
for (Path p : paths) {
contexts[i++] = new TaskControllerJobPathDeletionContext(fs, p, id, user,
taskController);
}
return contexts;
}
/**
* Builds list of TaskControllerTaskPathDeletionContext objects for a task
* @param fs : FileSystem in which the dirs to be deleted
* @param paths : mapred-local-dirs
* @param task : the task whose taskDir or taskWorkDir is going to be deleted
* @param isWorkDir : the dir to be deleted is workDir or taskDir
* @param taskController : the task-controller to be used for deletion of
* taskDir or taskWorkDir
*/
static PathDeletionContext[] buildTaskControllerTaskPathDeletionContexts(
FileSystem fs, Path[] paths, Task task, boolean isWorkDir,
TaskController taskController)
throws IOException {
int i = 0;
PathDeletionContext[] contexts =
new TaskControllerPathDeletionContext[paths.length];
for (Path p : paths) {
contexts[i++] = new TaskControllerTaskPathDeletionContext(fs, p, task,
isWorkDir, taskController);
}
return contexts;
}
/**
* Send a signal to a stuck task commanding it to dump stack traces
* to stderr before we kill it with purgeTask().
*
* @param tip {@link TaskInProgress} to dump stack traces.
*/
private void dumpTaskStack(TaskInProgress tip) {
TaskRunner runner = tip.getTaskRunner();
if (null == runner) {
return; // tip is already abandoned.
}
JvmManager jvmMgr = runner.getJvmManager();
jvmMgr.dumpStack(runner);
}
/**
* The task tracker is done with this job, so we need to clean up.
* @param action The action with the job
* @throws IOException
*/
synchronized void purgeJob(KillJobAction action) throws IOException {
JobID jobId = action.getJobID();
LOG.info("Received 'KillJobAction' for job: " + jobId);
RunningJob rjob = null;
synchronized (runningJobs) {
rjob = runningJobs.get(jobId);
}
if (rjob == null) {
LOG.warn("Unknown job " + jobId + " being deleted.");
} else {
synchronized (rjob) {
// Add this tips of this job to queue of tasks to be purged
for (TaskInProgress tip : rjob.tasks) {
tip.jobHasFinished(false);
Task t = tip.getTask();
if (t.isMapTask()) {
indexCache.removeMap(tip.getTask().getTaskID().toString());
}
}
// Delete the job directory for this
// task if the job is done/failed
if (!rjob.keepJobFiles) {
removeJobFiles(rjob.jobConf.getUser(), rjob.getJobID());
}
// add job to taskLogCleanupThread
long now = System.currentTimeMillis();
taskLogCleanupThread.markJobLogsForDeletion(now, rjob.jobConf,
rjob.jobid);
// Remove this job
rjob.tasks.clear();
}
}
synchronized(runningJobs) {
runningJobs.remove(jobId);
}
getJobTokenSecretManager().removeTokenForJob(jobId.toString());
}
/**
* This job's files are no longer needed on this TT, remove them.
*
* @param rjob
* @throws IOException
*/
void removeJobFiles(String user, JobID jobId)
throws IOException {
PathDeletionContext[] contexts =
buildTaskControllerJobPathDeletionContexts(localFs,
getLocalFiles(fConf, ""), jobId, user, taskController);
directoryCleanupThread.addToQueue(contexts);
}
/**
* Remove the tip and update all relevant state.
*
* @param tip {@link TaskInProgress} to be removed.
* @param wasFailure did the task fail or was it killed?
*/
private void purgeTask(TaskInProgress tip, boolean wasFailure)
throws IOException {
if (tip != null) {
LOG.info("About to purge task: " + tip.getTask().getTaskID());
// Remove the task from running jobs,
// removing the job if it's the last task
removeTaskFromJob(tip.getTask().getJobID(), tip);
tip.jobHasFinished(wasFailure);
if (tip.getTask().isMapTask()) {
indexCache.removeMap(tip.getTask().getTaskID().toString());
}
}
}
/** Check if we're dangerously low on disk space
* If so, kill jobs to free up space and make sure
* we don't accept any new tasks
* Try killing the reduce jobs first, since I believe they
* use up most space
* Then pick the one with least progress
*/
private void killOverflowingTasks() throws IOException {
long localMinSpaceKill;
synchronized(this){
localMinSpaceKill = minSpaceKill;
}
if (!enoughFreeSpace(localMinSpaceKill)) {
acceptNewTasks=false;
//we give up! do not accept new tasks until
//all the ones running have finished and they're all cleared up
synchronized (this) {
TaskInProgress killMe = findTaskToKill(null);
if (killMe!=null) {
String msg = "Tasktracker running out of space." +
" Killing task.";
LOG.info(killMe.getTask().getTaskID() + ": " + msg);
killMe.reportDiagnosticInfo(msg);
purgeTask(killMe, false);
}
}
}
}
/**
* Pick a task to kill to free up memory/disk-space
* @param tasksToExclude tasks that are to be excluded while trying to find a
* task to kill. If null, all runningTasks will be searched.
* @return the task to kill or null, if one wasn't found
*/
synchronized TaskInProgress findTaskToKill(List<TaskAttemptID> tasksToExclude) {
TaskInProgress killMe = null;
for (Iterator it = runningTasks.values().iterator(); it.hasNext();) {
TaskInProgress tip = (TaskInProgress) it.next();
if (tasksToExclude != null
&& tasksToExclude.contains(tip.getTask().getTaskID())) {
// exclude this task
continue;
}
if ((tip.getRunState() == TaskStatus.State.RUNNING ||
tip.getRunState() == TaskStatus.State.COMMIT_PENDING) &&
!tip.wasKilled) {
if (killMe == null) {
killMe = tip;
} else if (!tip.getTask().isMapTask()) {
//reduce task, give priority
if (killMe.getTask().isMapTask() ||
(tip.getTask().getProgress().get() <
killMe.getTask().getProgress().get())) {
killMe = tip;
}
} else if (killMe.getTask().isMapTask() &&
tip.getTask().getProgress().get() <
killMe.getTask().getProgress().get()) {
//map task, only add if the progress is lower
killMe = tip;
}
}
}
return killMe;
}
/**
* Check if any of the local directories has enough
* free space (more than minSpace)
*
* If not, do not try to get a new task assigned
* @return
* @throws IOException
*/
private boolean enoughFreeSpace(long minSpace) throws IOException {
if (minSpace == 0) {
return true;
}
return minSpace < getFreeSpace();
}
private long getFreeSpace() throws IOException {
long biggestSeenSoFar = 0;
String[] localDirs = fConf.getLocalDirs();
for (int i = 0; i < localDirs.length; i++) {
DF df = null;
if (localDirsDf.containsKey(localDirs[i])) {
df = localDirsDf.get(localDirs[i]);
} else {
df = new DF(new File(localDirs[i]), fConf);
localDirsDf.put(localDirs[i], df);
}
long availOnThisVol = df.getAvailable();
if (availOnThisVol > biggestSeenSoFar) {
biggestSeenSoFar = availOnThisVol;
}
}
//Should ultimately hold back the space we expect running tasks to use but
//that estimate isn't currently being passed down to the TaskTrackers
return biggestSeenSoFar;
}
private TaskLauncher mapLauncher;
private TaskLauncher reduceLauncher;
public JvmManager getJvmManagerInstance() {
return jvmManager;
}
// called from unit test
void setJvmManagerInstance(JvmManager jvmManager) {
this.jvmManager = jvmManager;
}
private void addToTaskQueue(LaunchTaskAction action) {
if (action.getTask().isMapTask()) {
mapLauncher.addToTaskQueue(action);
} else {
reduceLauncher.addToTaskQueue(action);
}
}
// This method is called from unit tests
int getFreeSlots(boolean isMap) {
if (isMap) {
return mapLauncher.numFreeSlots.get();
} else {
return reduceLauncher.numFreeSlots.get();
}
}
class TaskLauncher extends Thread {
private IntWritable numFreeSlots;
private final int maxSlots;
private List<TaskInProgress> tasksToLaunch;
public TaskLauncher(TaskType taskType, int numSlots) {
this.maxSlots = numSlots;
this.numFreeSlots = new IntWritable(numSlots);
this.tasksToLaunch = new LinkedList<TaskInProgress>();
setDaemon(true);
setName("TaskLauncher for " + taskType + " tasks");
}
public void addToTaskQueue(LaunchTaskAction action) {
synchronized (tasksToLaunch) {
TaskInProgress tip = registerTask(action, this);
tasksToLaunch.add(tip);
tasksToLaunch.notifyAll();
}
}
public void cleanTaskQueue() {
tasksToLaunch.clear();
}
public void addFreeSlots(int numSlots) {
synchronized (numFreeSlots) {
numFreeSlots.set(numFreeSlots.get() + numSlots);
assert (numFreeSlots.get() <= maxSlots);
LOG.info("addFreeSlot : current free slots : " + numFreeSlots.get());
numFreeSlots.notifyAll();
}
}
void notifySlots() {
synchronized (numFreeSlots) {
numFreeSlots.notifyAll();
}
}
int getNumWaitingTasksToLaunch() {
synchronized (tasksToLaunch) {
return tasksToLaunch.size();
}
}
public void run() {
while (!Thread.interrupted()) {
try {
TaskInProgress tip;
Task task;
synchronized (tasksToLaunch) {
while (tasksToLaunch.isEmpty()) {
tasksToLaunch.wait();
}
//get the TIP
tip = tasksToLaunch.remove(0);
task = tip.getTask();
LOG.info("Trying to launch : " + tip.getTask().getTaskID() +
" which needs " + task.getNumSlotsRequired() + " slots");
}
//wait for free slots to run
synchronized (numFreeSlots) {
boolean canLaunch = true;
while (numFreeSlots.get() < task.getNumSlotsRequired()) {
//Make sure that there is no kill task action for this task!
//We are not locking tip here, because it would reverse the
//locking order!
//Also, Lock for the tip is not required here! because :
// 1. runState of TaskStatus is volatile
// 2. Any notification is not missed because notification is
// synchronized on numFreeSlots. So, while we are doing the check,
// if the tip is half way through the kill(), we don't miss
// notification for the following wait().
if (!tip.canBeLaunched()) {
//got killed externally while still in the launcher queue
LOG.info("Not blocking slots for " + task.getTaskID()
+ " as it got killed externally. Task's state is "
+ tip.getRunState());
canLaunch = false;
break;
}
LOG.info("TaskLauncher : Waiting for " + task.getNumSlotsRequired() +
" to launch " + task.getTaskID() + ", currently we have " +
numFreeSlots.get() + " free slots");
numFreeSlots.wait();
}
if (!canLaunch) {
continue;
}
LOG.info("In TaskLauncher, current free slots : " + numFreeSlots.get()+
" and trying to launch "+tip.getTask().getTaskID() +
" which needs " + task.getNumSlotsRequired() + " slots");
numFreeSlots.set(numFreeSlots.get() - task.getNumSlotsRequired());
assert (numFreeSlots.get() >= 0);
}
synchronized (tip) {
//to make sure that there is no kill task action for this
if (!tip.canBeLaunched()) {
//got killed externally while still in the launcher queue
LOG.info("Not launching task " + task.getTaskID() + " as it got"
+ " killed externally. Task's state is " + tip.getRunState());
addFreeSlots(task.getNumSlotsRequired());
continue;
}
tip.slotTaken = true;
}
//got a free slot. launch the task
startNewTask(tip);
} catch (InterruptedException e) {
return; // ALL DONE
} catch (Throwable th) {
LOG.error("TaskLauncher error " +
StringUtils.stringifyException(th));
}
}
}
}
private TaskInProgress registerTask(LaunchTaskAction action,
TaskLauncher launcher) {
Task t = action.getTask();
LOG.info("LaunchTaskAction (registerTask): " + t.getTaskID() +
" task's state:" + t.getState());
TaskInProgress tip = new TaskInProgress(t, this.fConf, launcher);
synchronized (this) {
tasks.put(t.getTaskID(), tip);
runningTasks.put(t.getTaskID(), tip);
boolean isMap = t.isMapTask();
if (isMap) {
mapTotal++;
} else {
reduceTotal++;
}
}
return tip;
}
/**
* Start a new task.
* All exceptions are handled locally, so that we don't mess up the
* task tracker.
*/
void startNewTask(TaskInProgress tip) {
try {
RunningJob rjob = localizeJob(tip);
launchTaskForJob(tip, new JobConf(rjob.jobConf));
} catch (Throwable e) {
String msg = ("Error initializing " + tip.getTask().getTaskID() +
":\n" + StringUtils.stringifyException(e));
LOG.warn(msg);
tip.reportDiagnosticInfo(msg);
try {
tip.kill(true);
tip.cleanup(true);
} catch (IOException ie2) {
LOG.info("Error cleaning up " + tip.getTask().getTaskID() + ":\n" +
StringUtils.stringifyException(ie2));
}
// Careful!
// This might not be an 'Exception' - don't handle 'Error' here!
if (e instanceof Error) {
throw ((Error) e);
}
}
}
void addToMemoryManager(TaskAttemptID attemptId, boolean isMap,
JobConf conf) {
if (!isTaskMemoryManagerEnabled()) {
return; // Skip this if TaskMemoryManager is not enabled.
}
// Obtain physical memory limits from the job configuration
long physicalMemoryLimit =
conf.getLong(isMap ? MRJobConfig.MAP_MEMORY_PHYSICAL_MB :
MRJobConfig.REDUCE_MEMORY_PHYSICAL_MB,
JobConf.DISABLED_MEMORY_LIMIT);
if (physicalMemoryLimit > 0) {
physicalMemoryLimit *= 1024L * 1024L;
}
// Obtain virtual memory limits from the job configuration
long virtualMemoryLimit = isMap ?
conf.getMemoryForMapTask() * 1024 * 1024 :
conf.getMemoryForReduceTask() * 1024 * 1024;
taskMemoryManager.addTask(attemptId, virtualMemoryLimit,
physicalMemoryLimit);
}
void removeFromMemoryManager(TaskAttemptID attemptId) {
// Remove the entry from taskMemoryManagerThread's data structures.
if (isTaskMemoryManagerEnabled()) {
taskMemoryManager.removeTask(attemptId);
}
}
/**
* Notify the tasktracker to send an out-of-band heartbeat.
*/
private void notifyTTAboutTaskCompletion() {
if (oobHeartbeatOnTaskCompletion) {
synchronized (finishedCount) {
int value = finishedCount.get();
finishedCount.set(value+1);
finishedCount.notify();
}
}
}
/**
* The server retry loop.
* This while-loop attempts to connect to the JobTracker. It only
* loops when the old TaskTracker has gone bad (its state is
* stale somehow) and we need to reinitialize everything.
*/
public void run() {
try {
startCleanupThreads();
boolean denied = false;
while (running && !shuttingDown && !denied) {
boolean staleState = false;
try {
// This while-loop attempts reconnects if we get network errors
while (running && !staleState && !shuttingDown && !denied) {
try {
State osState = offerService();
if (osState == State.STALE) {
staleState = true;
} else if (osState == State.DENIED) {
denied = true;
}
} catch (Exception ex) {
if (!shuttingDown) {
LOG.info("Lost connection to JobTracker [" +
jobTrackAddr + "]. Retrying...", ex);
try {
Thread.sleep(5000);
} catch (InterruptedException ie) {
}
}
}
}
} finally {
close();
}
if (shuttingDown) { return; }
LOG.warn("Reinitializing local state");
initialize();
}
if (denied) {
shutdown();
}
} catch (IOException iex) {
LOG.error("Got fatal exception while reinitializing TaskTracker: " +
StringUtils.stringifyException(iex));
return;
}
catch (InterruptedException i) {
LOG.error("Got interrupted while reinitializing TaskTracker: " +
i.getMessage());
return;
}
}
///////////////////////////////////////////////////////
// TaskInProgress maintains all the info for a Task that
// lives at this TaskTracker. It maintains the Task object,
// its TaskStatus, and the TaskRunner.
///////////////////////////////////////////////////////
class TaskInProgress {
Task task;
long lastProgressReport;
StringBuffer diagnosticInfo = new StringBuffer();
private TaskRunner runner;
volatile boolean done = false;
volatile boolean wasKilled = false;
private JobConf defaultJobConf;
private JobConf localJobConf;
private boolean keepFailedTaskFiles;
private boolean alwaysKeepTaskFiles;
private TaskStatus taskStatus;
private long taskTimeout;
private String debugCommand;
private volatile boolean slotTaken = false;
private TaskLauncher launcher;
/**
*/
public TaskInProgress(Task task, JobConf conf) {
this(task, conf, null);
}
public TaskInProgress(Task task, JobConf conf, TaskLauncher launcher) {
this.task = task;
this.launcher = launcher;
this.lastProgressReport = System.currentTimeMillis();
this.defaultJobConf = conf;
localJobConf = null;
taskStatus = TaskStatus.createTaskStatus(task.isMapTask(), task.getTaskID(),
0.0f,
task.getNumSlotsRequired(),
task.getState(),
diagnosticInfo.toString(),
"initializing",
getName(),
task.isTaskCleanupTask() ?
TaskStatus.Phase.CLEANUP :
task.isMapTask()? TaskStatus.Phase.MAP:
TaskStatus.Phase.SHUFFLE,
task.getCounters());
taskTimeout = (10 * 60 * 1000);
}
void localizeTask(Task task) throws IOException{
FileSystem localFs = FileSystem.getLocal(fConf);
// create taskDirs on all the disks.
getLocalizer().initializeAttemptDirs(task.getUser(),
task.getJobID().toString(), task.getTaskID().toString(),
task.isTaskCleanupTask());
// create the working-directory of the task
Path cwd =
lDirAlloc.getLocalPathForWrite(getTaskWorkDir(task.getUser(), task
.getJobID().toString(), task.getTaskID().toString(), task
.isTaskCleanupTask()), defaultJobConf);
if (!localFs.mkdirs(cwd)) {
throw new IOException("Mkdirs failed to create "
+ cwd.toString());
}
localJobConf.set(LOCAL_DIR,
fConf.get(LOCAL_DIR));
if (fConf.get(TT_HOST_NAME) != null) {
localJobConf.set(TT_HOST_NAME, fConf.get(TT_HOST_NAME));
}
keepFailedTaskFiles = localJobConf.getKeepFailedTaskFiles();
// Do the task-type specific localization
task.localizeConfiguration(localJobConf);
List<String[]> staticResolutions = NetUtils.getAllStaticResolutions();
if (staticResolutions != null && staticResolutions.size() > 0) {
StringBuffer str = new StringBuffer();
for (int i = 0; i < staticResolutions.size(); i++) {
String[] hostToResolved = staticResolutions.get(i);
str.append(hostToResolved[0]+"="+hostToResolved[1]);
if (i != staticResolutions.size() - 1) {
str.append(',');
}
}
localJobConf.set(TT_STATIC_RESOLUTIONS, str.toString());
}
if (task.isMapTask()) {
debugCommand = localJobConf.getMapDebugScript();
} else {
debugCommand = localJobConf.getReduceDebugScript();
}
String keepPattern = localJobConf.getKeepTaskFilesPattern();
if (keepPattern != null) {
alwaysKeepTaskFiles =
Pattern.matches(keepPattern, task.getTaskID().toString());
} else {
alwaysKeepTaskFiles = false;
}
if (debugCommand != null || localJobConf.getProfileEnabled() ||
alwaysKeepTaskFiles || keepFailedTaskFiles) {
//disable jvm reuse
localJobConf.setNumTasksToExecutePerJvm(1);
}
task.setConf(localJobConf);
}
/**
*/
public Task getTask() {
return task;
}
TaskRunner getTaskRunner() {
return runner;
}
void setTaskRunner(TaskRunner rnr) {
this.runner = rnr;
}
public synchronized void setJobConf(JobConf lconf){
this.localJobConf = lconf;
keepFailedTaskFiles = localJobConf.getKeepFailedTaskFiles();
taskTimeout = localJobConf.getLong(MRJobConfig.TASK_TIMEOUT,
10 * 60 * 1000);
}
public synchronized JobConf getJobConf() {
return localJobConf;
}
/**
*/
public synchronized TaskStatus getStatus() {
taskStatus.setDiagnosticInfo(diagnosticInfo.toString());
if (diagnosticInfo.length() > 0) {
diagnosticInfo = new StringBuffer();
}
return taskStatus;
}
/**
* Kick off the task execution
*/
public synchronized void launchTask() throws IOException {
if (this.taskStatus.getRunState() == TaskStatus.State.UNASSIGNED ||
this.taskStatus.getRunState() == TaskStatus.State.FAILED_UNCLEAN ||
this.taskStatus.getRunState() == TaskStatus.State.KILLED_UNCLEAN) {
localizeTask(task);
if (this.taskStatus.getRunState() == TaskStatus.State.UNASSIGNED) {
this.taskStatus.setRunState(TaskStatus.State.RUNNING);
}
setTaskRunner(task.createRunner(TaskTracker.this, this));
this.runner.start();
this.taskStatus.setStartTime(System.currentTimeMillis());
} else {
LOG.info("Not launching task: " + task.getTaskID() +
" since it's state is " + this.taskStatus.getRunState());
}
}
boolean isCleaningup() {
return this.taskStatus.inTaskCleanupPhase();
}
// checks if state has been changed for the task to be launched
boolean canBeLaunched() {
return (getRunState() == TaskStatus.State.UNASSIGNED ||
getRunState() == TaskStatus.State.FAILED_UNCLEAN ||
getRunState() == TaskStatus.State.KILLED_UNCLEAN);
}
/**
* The task is reporting its progress
*/
public synchronized void reportProgress(TaskStatus taskStatus)
{
LOG.info(task.getTaskID() + " " + taskStatus.getProgress() +
"% " + taskStatus.getStateString());
// task will report its state as
// COMMIT_PENDING when it is waiting for commit response and
// when it is committing.
// cleanup attempt will report its state as FAILED_UNCLEAN/KILLED_UNCLEAN
if (this.done ||
(this.taskStatus.getRunState() != TaskStatus.State.RUNNING &&
this.taskStatus.getRunState() != TaskStatus.State.COMMIT_PENDING &&
!isCleaningup()) ||
((this.taskStatus.getRunState() == TaskStatus.State.COMMIT_PENDING ||
this.taskStatus.getRunState() == TaskStatus.State.FAILED_UNCLEAN ||
this.taskStatus.getRunState() == TaskStatus.State.KILLED_UNCLEAN) &&
taskStatus.getRunState() == TaskStatus.State.RUNNING)) {
//make sure we ignore progress messages after a task has
//invoked TaskUmbilicalProtocol.done() or if the task has been
//KILLED/FAILED/FAILED_UNCLEAN/KILLED_UNCLEAN
//Also ignore progress update if the state change is from
//COMMIT_PENDING/FAILED_UNCLEAN/KILLED_UNCLEA to RUNNING
LOG.info(task.getTaskID() + " Ignoring status-update since " +
((this.done) ? "task is 'done'" :
("runState: " + this.taskStatus.getRunState()))
);
return;
}
this.taskStatus.statusUpdate(taskStatus);
this.lastProgressReport = System.currentTimeMillis();
}
/**
*/
public long getLastProgressReport() {
return lastProgressReport;
}
/**
*/
public TaskStatus.State getRunState() {
return taskStatus.getRunState();
}
/**
* The task's configured timeout.
*
* @return the task's configured timeout.
*/
public long getTaskTimeout() {
return taskTimeout;
}
/**
* The task has reported some diagnostic info about its status
*/
public synchronized void reportDiagnosticInfo(String info) {
this.diagnosticInfo.append(info);
}
public synchronized void reportNextRecordRange(SortedRanges.Range range) {
this.taskStatus.setNextRecordRange(range);
}
/**
* The task is reporting that it's done running
*/
public synchronized void reportDone() {
if (isCleaningup()) {
if (this.taskStatus.getRunState() == TaskStatus.State.FAILED_UNCLEAN) {
this.taskStatus.setRunState(TaskStatus.State.FAILED);
} else if (this.taskStatus.getRunState() ==
TaskStatus.State.KILLED_UNCLEAN) {
this.taskStatus.setRunState(TaskStatus.State.KILLED);
}
} else {
this.taskStatus.setRunState(TaskStatus.State.SUCCEEDED);
}
this.taskStatus.setProgress(1.0f);
this.taskStatus.setFinishTime(System.currentTimeMillis());
this.done = true;
jvmManager.taskFinished(runner);
runner.signalDone();
LOG.info("Task " + task.getTaskID() + " is done.");
LOG.info("reported output size for " + task.getTaskID() + " was " + taskStatus.getOutputSize());
}
public boolean wasKilled() {
return wasKilled;
}
/**
* A task is reporting in as 'done'.
*
* We need to notify the tasktracker to send an out-of-band heartbeat.
* If isn't <code>commitPending</code>, we need to finalize the task
* and release the slot it's occupied.
*
* @param commitPending is the task-commit pending?
*/
void reportTaskFinished(boolean commitPending) {
if (!commitPending) {
try {
taskFinished();
} finally {
releaseSlot();
}
}
notifyTTAboutTaskCompletion();
}
/* State changes:
* RUNNING/COMMIT_PENDING -> FAILED_UNCLEAN/FAILED/KILLED_UNCLEAN/KILLED
* FAILED_UNCLEAN -> FAILED
* KILLED_UNCLEAN -> KILLED
*/
private void setTaskFailState(boolean wasFailure) {
// go FAILED_UNCLEAN -> FAILED and KILLED_UNCLEAN -> KILLED always
if (taskStatus.getRunState() == TaskStatus.State.FAILED_UNCLEAN) {
taskStatus.setRunState(TaskStatus.State.FAILED);
} else if (taskStatus.getRunState() ==
TaskStatus.State.KILLED_UNCLEAN) {
taskStatus.setRunState(TaskStatus.State.KILLED);
} else if (task.isMapOrReduce() &&
taskStatus.getPhase() != TaskStatus.Phase.CLEANUP) {
if (wasFailure) {
taskStatus.setRunState(TaskStatus.State.FAILED_UNCLEAN);
} else {
taskStatus.setRunState(TaskStatus.State.KILLED_UNCLEAN);
}
} else {
if (wasFailure) {
taskStatus.setRunState(TaskStatus.State.FAILED);
} else {
taskStatus.setRunState(TaskStatus.State.KILLED);
}
}
}
/**
* The task has actually finished running.
*/
public void taskFinished() {
long start = System.currentTimeMillis();
//
// Wait until task reports as done. If it hasn't reported in,
// wait for a second and try again.
//
while (!done && (System.currentTimeMillis() - start < WAIT_FOR_DONE)) {
try {
Thread.sleep(1000);
} catch (InterruptedException ie) {
}
}
//
// Change state to success or failure, depending on whether
// task was 'done' before terminating
//
boolean needCleanup = false;
synchronized (this) {
// Remove the task from MemoryManager, if the task SUCCEEDED or FAILED.
// KILLED tasks are removed in method kill(), because Kill
// would result in launching a cleanup attempt before
// TaskRunner returns; if remove happens here, it would remove
// wrong task from memory manager.
if (done || !wasKilled) {
removeFromMemoryManager(task.getTaskID());
}
if (!done) {
if (!wasKilled) {
failures += 1;
setTaskFailState(true);
// call the script here for the failed tasks.
if (debugCommand != null) {
try {
runDebugScript();
} catch (Exception e) {
String msg =
"Debug-script could not be run successfully : "
+ StringUtils.stringifyException(e);
LOG.warn(msg);
reportDiagnosticInfo(msg);
}
}
}
taskStatus.setProgress(0.0f);
}
this.taskStatus.setFinishTime(System.currentTimeMillis());
needCleanup = (taskStatus.getRunState() == TaskStatus.State.FAILED ||
taskStatus.getRunState() == TaskStatus.State.FAILED_UNCLEAN ||
taskStatus.getRunState() == TaskStatus.State.KILLED_UNCLEAN ||
taskStatus.getRunState() == TaskStatus.State.KILLED);
}
//
// If the task has failed, or if the task was killAndCleanup()'ed,
// we should clean up right away. We only wait to cleanup
// if the task succeeded, and its results might be useful
// later on to downstream job processing.
//
if (needCleanup) {
removeTaskFromJob(task.getJobID(), this);
}
cleanup(needCleanup);
}
/**
* Run the debug-script now. Because debug-script can be user code, we use
* {@link TaskController} to execute the debug script.
*
* @throws IOException
*/
private void runDebugScript() throws IOException {
String taskStdout ="";
String taskStderr ="";
String taskSyslog ="";
String jobConf = task.getJobFile();
try {
// get task's stdout file
taskStdout = FileUtil
.makeShellPath(TaskLog.getRealTaskLogFileLocation(task.getTaskID(),
task.isTaskCleanupTask(), TaskLog.LogName.STDOUT));
// get task's stderr file
taskStderr = FileUtil
.makeShellPath(TaskLog.getRealTaskLogFileLocation(task.getTaskID(),
task.isTaskCleanupTask(), TaskLog.LogName.STDERR));
// get task's syslog file
taskSyslog = FileUtil
.makeShellPath(TaskLog.getRealTaskLogFileLocation(task.getTaskID(),
task.isTaskCleanupTask(), TaskLog.LogName.SYSLOG));
} catch(Exception e){
LOG.warn("Exception finding task's stdout/err/syslog files", e);
}
File workDir = new File(lDirAlloc.getLocalPathToRead(
TaskTracker.getLocalTaskDir(task.getUser(), task.getJobID()
.toString(), task.getTaskID().toString(), task
.isTaskCleanupTask())
+ Path.SEPARATOR + MRConstants.WORKDIR, localJobConf).toString());
// Build the command
File stdout = TaskLog.getTaskLogFile(task.getTaskID(), task
.isTaskCleanupTask(), TaskLog.LogName.DEBUGOUT);
// add pipes program as argument if it exists.
String program ="";
String executable = Submitter.getExecutable(localJobConf);
if ( executable != null) {
try {
program = new URI(executable).getFragment();
} catch (URISyntaxException ur) {
LOG.warn("Problem in the URI fragment for pipes executable");
}
}
String [] debug = debugCommand.split(" ");
List<String> vargs = new ArrayList<String>();
for (String component : debug) {
vargs.add(component);
}
vargs.add(taskStdout);
vargs.add(taskStderr);
vargs.add(taskSyslog);
vargs.add(jobConf);
vargs.add(program);
DebugScriptContext context =
new TaskController.DebugScriptContext();
context.args = vargs;
context.stdout = stdout;
context.workDir = workDir;
context.task = task;
getTaskController().runDebugScript(context);
// add the lines of debug out to diagnostics
int num = localJobConf.getInt(MRJobConfig.TASK_DEBUGOUT_LINES, -1);
addDiagnostics(FileUtil.makeShellPath(stdout), num, "DEBUG OUT");
}
/**
* Add last 'num' lines of the given file to the diagnostics.
* if num =-1, all the lines of file are added to the diagnostics.
* @param file The file from which to collect diagnostics.
* @param num The number of lines to be sent to diagnostics.
* @param tag The tag is printed before the diagnostics are printed.
*/
public void addDiagnostics(String file, int num, String tag) {
RandomAccessFile rafile = null;
try {
rafile = new RandomAccessFile(file,"r");
int no_lines =0;
String line = null;
StringBuffer tail = new StringBuffer();
tail.append("\n-------------------- "+tag+"---------------------\n");
String[] lines = null;
if (num >0) {
lines = new String[num];
}
while ((line = rafile.readLine()) != null) {
no_lines++;
if (num >0) {
if (no_lines <= num) {
lines[no_lines-1] = line;
}
else { // shift them up
for (int i=0; i<num-1; ++i) {
lines[i] = lines[i+1];
}
lines[num-1] = line;
}
}
else if (num == -1) {
tail.append(line);
tail.append("\n");
}
}
int n = no_lines > num ?num:no_lines;
if (num >0) {
for (int i=0;i<n;i++) {
tail.append(lines[i]);
tail.append("\n");
}
}
if(n!=0)
reportDiagnosticInfo(tail.toString());
} catch (FileNotFoundException fnfe){
LOG.warn("File "+file+ " not found");
} catch (IOException ioe){
LOG.warn("Error reading file "+file);
} finally {
try {
if (rafile != null) {
rafile.close();
}
} catch (IOException ioe) {
LOG.warn("Error closing file "+file);
}
}
}
/**
* We no longer need anything from this task, as the job has
* finished. If the task is still running, kill it and clean up.
*
* @param wasFailure did the task fail, as opposed to was it killed by
* the framework
*/
public void jobHasFinished(boolean wasFailure) throws IOException {
// Kill the task if it is still running
synchronized(this){
if (getRunState() == TaskStatus.State.RUNNING ||
getRunState() == TaskStatus.State.UNASSIGNED ||
getRunState() == TaskStatus.State.COMMIT_PENDING ||
isCleaningup()) {
kill(wasFailure);
}
}
// Cleanup on the finished task
cleanup(true);
}
/**
* Something went wrong and the task must be killed.
*
* @param wasFailure was it a failure (versus a kill request)?
*/
public synchronized void kill(boolean wasFailure) throws IOException {
if (taskStatus.getRunState() == TaskStatus.State.RUNNING ||
taskStatus.getRunState() == TaskStatus.State.COMMIT_PENDING ||
isCleaningup()) {
wasKilled = true;
if (wasFailure) {
failures += 1;
}
// runner could be null if task-cleanup attempt is not localized yet
if (runner != null) {
runner.kill();
}
setTaskFailState(wasFailure);
} else if (taskStatus.getRunState() == TaskStatus.State.UNASSIGNED) {
if (wasFailure) {
failures += 1;
taskStatus.setRunState(TaskStatus.State.FAILED);
} else {
taskStatus.setRunState(TaskStatus.State.KILLED);
}
}
taskStatus.setFinishTime(System.currentTimeMillis());
removeFromMemoryManager(task.getTaskID());
releaseSlot();
notifyTTAboutTaskCompletion();
}
private synchronized void releaseSlot() {
if (slotTaken) {
if (launcher != null) {
launcher.addFreeSlots(task.getNumSlotsRequired());
}
slotTaken = false;
} else {
// wake up the launcher. it may be waiting to block slots for this task.
if (launcher != null) {
launcher.notifySlots();
}
}
}
/**
* The map output has been lost.
*/
private synchronized void mapOutputLost(String failure
) throws IOException {
if (taskStatus.getRunState() == TaskStatus.State.COMMIT_PENDING ||
taskStatus.getRunState() == TaskStatus.State.SUCCEEDED) {
// change status to failure
LOG.info("Reporting output lost:"+task.getTaskID());
taskStatus.setRunState(TaskStatus.State.FAILED);
taskStatus.setProgress(0.0f);
reportDiagnosticInfo("Map output lost, rescheduling: " +
failure);
runningTasks.put(task.getTaskID(), this);
mapTotal++;
} else {
LOG.warn("Output already reported lost:"+task.getTaskID());
}
}
/**
* We no longer need anything from this task. Either the
* controlling job is all done and the files have been copied
* away, or the task failed and we don't need the remains.
* Any calls to cleanup should not lock the tip first.
* cleanup does the right thing- updates tasks in Tasktracker
* by locking tasktracker first and then locks the tip.
*
* if needCleanup is true, the whole task directory is cleaned up.
* otherwise the current working directory of the task
* i.e. <taskid>/work is cleaned up.
*/
void cleanup(boolean needCleanup) {
TaskAttemptID taskId = task.getTaskID();
LOG.debug("Cleaning up " + taskId);
synchronized (TaskTracker.this) {
if (needCleanup) {
// see if tasks data structure is holding this tip.
// tasks could hold the tip for cleanup attempt, if cleanup attempt
// got launched before this method.
if (tasks.get(taskId) == this) {
tasks.remove(taskId);
}
}
synchronized (this){
if (alwaysKeepTaskFiles ||
(taskStatus.getRunState() == TaskStatus.State.FAILED &&
keepFailedTaskFiles)) {
return;
}
}
}
synchronized (this) {
// localJobConf could be null if localization has not happened
// then no cleanup will be required.
if (localJobConf == null) {
return;
}
try {
removeTaskFiles(needCleanup, taskId);
} catch (Throwable ie) {
LOG.info("Error cleaning up task runner: "
+ StringUtils.stringifyException(ie));
}
}
}
/**
* Some or all of the files from this task are no longer required. Remove
* them via CleanupQueue.
*
* @param needCleanup
* @param taskId
* @throws IOException
*/
void removeTaskFiles(boolean needCleanup, TaskAttemptID taskId)
throws IOException {
if (needCleanup) {
if (runner != null) {
// cleans up the output directory of the task (where map outputs
// and reduce inputs get stored)
runner.close();
}
if (localJobConf.getNumTasksToExecutePerJvm() == 1) {
// No jvm reuse, remove everything
PathDeletionContext[] contexts =
buildTaskControllerTaskPathDeletionContexts(localFs,
getLocalFiles(fConf, ""), task, false/* not workDir */,
taskController);
directoryCleanupThread.addToQueue(contexts);
} else {
// Jvm reuse. We don't delete the workdir since some other task
// (running in the same JVM) might be using the dir. The JVM
// running the tasks would clean the workdir per a task in the
// task process itself.
String localTaskDir =
getLocalTaskDir(task.getUser(), task.getJobID().toString(), taskId
.toString(), task.isTaskCleanupTask());
PathDeletionContext[] contexts = buildPathDeletionContexts(
localFs, getLocalFiles(defaultJobConf, localTaskDir +
Path.SEPARATOR + TaskTracker.JOBFILE));
directoryCleanupThread.addToQueue(contexts);
}
} else {
if (localJobConf.getNumTasksToExecutePerJvm() == 1) {
PathDeletionContext[] contexts =
buildTaskControllerTaskPathDeletionContexts(localFs,
getLocalFiles(fConf, ""), task, true /* workDir */,
taskController);
directoryCleanupThread.addToQueue(contexts);
}
}
}
@Override
public boolean equals(Object obj) {
return (obj instanceof TaskInProgress) &&
task.getTaskID().equals
(((TaskInProgress) obj).getTask().getTaskID());
}
@Override
public int hashCode() {
return task.getTaskID().hashCode();
}
}
// ///////////////////////////////////////////////////////////////
// TaskUmbilicalProtocol
/////////////////////////////////////////////////////////////////
/**
* Called upon startup by the child process, to fetch Task data.
*/
public synchronized JvmTask getTask(JvmContext context)
throws IOException {
JVMId jvmId = context.jvmId;
// save pid of task JVM sent by child
jvmManager.setPidToJvm(jvmId, context.pid);
LOG.debug("JVM with ID : " + jvmId + " asked for a task");
if (!jvmManager.isJvmKnown(jvmId)) {
LOG.info("Killing unknown JVM " + jvmId);
return new JvmTask(null, true);
}
RunningJob rjob = runningJobs.get(jvmId.getJobId());
if (rjob == null) { //kill the JVM since the job is dead
LOG.info("Killing JVM " + jvmId + " since job " + jvmId.getJobId() +
" is dead");
jvmManager.killJvm(jvmId);
return new JvmTask(null, true);
}
TaskInProgress tip = jvmManager.getTaskForJvm(jvmId);
if (tip == null) {
return new JvmTask(null, false);
}
if (tasks.get(tip.getTask().getTaskID()) != null) { //is task still present
LOG.info("JVM with ID: " + jvmId + " given task: " +
tip.getTask().getTaskID());
return new JvmTask(tip.getTask(), false);
} else {
LOG.info("Killing JVM with ID: " + jvmId + " since scheduled task: " +
tip.getTask().getTaskID() + " is " + tip.taskStatus.getRunState());
return new JvmTask(null, true);
}
}
/**
* Called periodically to report Task progress, from 0.0 to 1.0.
*/
public synchronized boolean statusUpdate(TaskAttemptID taskid,
TaskStatus taskStatus)
throws IOException {
TaskInProgress tip = tasks.get(taskid);
if (tip != null) {
tip.reportProgress(taskStatus);
return true;
} else {
LOG.warn("Progress from unknown child task: "+taskid);
return false;
}
}
/**
* Called when the task dies before completion, and we want to report back
* diagnostic info
*/
public synchronized void reportDiagnosticInfo(TaskAttemptID taskid, String info) throws IOException {
TaskInProgress tip = tasks.get(taskid);
if (tip != null) {
tip.reportDiagnosticInfo(info);
} else {
LOG.warn("Error from unknown child task: "+taskid+". Ignored.");
}
}
public synchronized void reportNextRecordRange(TaskAttemptID taskid,
SortedRanges.Range range) throws IOException {
TaskInProgress tip = tasks.get(taskid);
if (tip != null) {
tip.reportNextRecordRange(range);
} else {
LOG.warn("reportNextRecordRange from unknown child task: "+taskid+". " +
"Ignored.");
}
}
/** Child checking to see if we're alive. Normally does nothing.*/
public synchronized boolean ping(TaskAttemptID taskid) throws IOException {
return tasks.get(taskid) != null;
}
/**
* Task is reporting that it is in commit_pending
* and it is waiting for the commit Response
*/
public synchronized void commitPending(TaskAttemptID taskid,
TaskStatus taskStatus)
throws IOException {
LOG.info("Task " + taskid + " is in commit-pending," +"" +
" task state:" +taskStatus.getRunState());
statusUpdate(taskid, taskStatus);
reportTaskFinished(taskid, true);
}
/**
* Child checking whether it can commit
*/
public synchronized boolean canCommit(TaskAttemptID taskid) {
return commitResponses.contains(taskid); //don't remove it now
}
/**
* The task is done.
*/
public synchronized void done(TaskAttemptID taskid)
throws IOException {
TaskInProgress tip = tasks.get(taskid);
commitResponses.remove(taskid);
if (tip != null) {
tip.reportDone();
} else {
LOG.warn("Unknown child task done: "+taskid+". Ignored.");
}
}
/**
* A reduce-task failed to shuffle the map-outputs. Kill the task.
*/
public synchronized void shuffleError(TaskAttemptID taskId, String message)
throws IOException {
LOG.fatal("Task: " + taskId + " - Killed due to Shuffle Failure: " + message);
TaskInProgress tip = runningTasks.get(taskId);
tip.reportDiagnosticInfo("Shuffle Error: " + message);
purgeTask(tip, true);
}
/**
* A child task had a local filesystem error. Kill the task.
*/
public synchronized void fsError(TaskAttemptID taskId, String message)
throws IOException {
LOG.fatal("Task: " + taskId + " - Killed due to FSError: " + message);
TaskInProgress tip = runningTasks.get(taskId);
tip.reportDiagnosticInfo("FSError: " + message);
purgeTask(tip, true);
}
/**
* A child task had a fatal error. Kill the task.
*/
public synchronized void fatalError(TaskAttemptID taskId, String msg)
throws IOException {
LOG.fatal("Task: " + taskId + " - exited : " + msg);
TaskInProgress tip = runningTasks.get(taskId);
tip.reportDiagnosticInfo("Error: " + msg);
purgeTask(tip, true);
}
public synchronized MapTaskCompletionEventsUpdate getMapCompletionEvents(
JobID jobId, int fromEventId, int maxLocs, TaskAttemptID id)
throws IOException {
TaskCompletionEvent[]mapEvents = TaskCompletionEvent.EMPTY_ARRAY;
synchronized (shouldReset) {
if (shouldReset.remove(id)) {
return new MapTaskCompletionEventsUpdate(mapEvents, true);
}
}
RunningJob rjob;
synchronized (runningJobs) {
rjob = runningJobs.get(jobId);
if (rjob != null) {
synchronized (rjob) {
FetchStatus f = rjob.getFetchStatus();
if (f != null) {
mapEvents = f.getMapEvents(fromEventId, maxLocs);
}
}
}
}
return new MapTaskCompletionEventsUpdate(mapEvents, false);
}
/////////////////////////////////////////////////////
// Called by TaskTracker thread after task process ends
/////////////////////////////////////////////////////
/**
* The task is no longer running. It may not have completed successfully
*/
void reportTaskFinished(TaskAttemptID taskid, boolean commitPending) {
TaskInProgress tip;
synchronized (this) {
tip = tasks.get(taskid);
}
if (tip != null) {
tip.reportTaskFinished(commitPending);
} else {
LOG.warn("Unknown child task finished: "+taskid+". Ignored.");
}
}
/**
* A completed map task's output has been lost.
*/
public synchronized void mapOutputLost(TaskAttemptID taskid,
String errorMsg) throws IOException {
TaskInProgress tip = tasks.get(taskid);
if (tip != null) {
tip.mapOutputLost(errorMsg);
} else {
LOG.warn("Unknown child with bad map output: "+taskid+". Ignored.");
}
}
/**
* The datastructure for initializing a job
*/
static class RunningJob{
private JobID jobid;
private JobConf jobConf;
// keep this for later use
volatile Set<TaskInProgress> tasks;
boolean localized;
boolean keepJobFiles;
UserGroupInformation ugi;
FetchStatus f;
RunningJob(JobID jobid) {
this.jobid = jobid;
localized = false;
tasks = new HashSet<TaskInProgress>();
keepJobFiles = false;
}
JobID getJobID() {
return jobid;
}
UserGroupInformation getUGI() {
return ugi;
}
void setFetchStatus(FetchStatus f) {
this.f = f;
}
FetchStatus getFetchStatus() {
return f;
}
JobConf getJobConf() {
return jobConf;
}
}
/**
* Get the name for this task tracker.
* @return the string like "tracker_mymachine:50010"
*/
String getName() {
return taskTrackerName;
}
private synchronized List<TaskStatus> cloneAndResetRunningTaskStatuses(
boolean sendCounters) {
List<TaskStatus> result = new ArrayList<TaskStatus>(runningTasks.size());
for(TaskInProgress tip: runningTasks.values()) {
TaskStatus status = tip.getStatus();
status.setIncludeCounters(sendCounters);
// send counters for finished or failed tasks and commit pending tasks
if (status.getRunState() != TaskStatus.State.RUNNING) {
status.setIncludeCounters(true);
}
result.add((TaskStatus)status.clone());
status.clearStatus();
}
return result;
}
/**
* Get the list of tasks that will be reported back to the
* job tracker in the next heartbeat cycle.
* @return a copy of the list of TaskStatus objects
*/
synchronized List<TaskStatus> getRunningTaskStatuses() {
List<TaskStatus> result = new ArrayList<TaskStatus>(runningTasks.size());
for(TaskInProgress tip: runningTasks.values()) {
result.add(tip.getStatus());
}
return result;
}
/**
* Get the list of stored tasks on this task tracker.
* @return
*/
synchronized List<TaskStatus> getNonRunningTasks() {
List<TaskStatus> result = new ArrayList<TaskStatus>(tasks.size());
for(Map.Entry<TaskAttemptID, TaskInProgress> task: tasks.entrySet()) {
if (!runningTasks.containsKey(task.getKey())) {
result.add(task.getValue().getStatus());
}
}
return result;
}
/**
* Get the list of tasks from running jobs on this task tracker.
* @return a copy of the list of TaskStatus objects
*/
synchronized List<TaskStatus> getTasksFromRunningJobs() {
List<TaskStatus> result = new ArrayList<TaskStatus>(tasks.size());
for (Map.Entry <JobID, RunningJob> item : runningJobs.entrySet()) {
RunningJob rjob = item.getValue();
synchronized (rjob) {
for (TaskInProgress tip : rjob.tasks) {
result.add(tip.getStatus());
}
}
}
return result;
}
/**
* Get the default job conf for this tracker.
*/
JobConf getJobConf() {
return fConf;
}
/**
* Check if the given local directories
* (and parent directories, if necessary) can be created.
* @param localDirs where the new TaskTracker should keep its local files.
* @throws DiskErrorException if all local directories are not writable
*/
private static void checkLocalDirs(String[] localDirs)
throws DiskErrorException {
boolean writable = false;
if (localDirs != null) {
for (int i = 0; i < localDirs.length; i++) {
try {
DiskChecker.checkDir(new File(localDirs[i]));
writable = true;
} catch(DiskErrorException e) {
LOG.warn("Task Tracker local " + e.getMessage());
}
}
}
if (!writable)
throw new DiskErrorException(
"all local directories are not writable");
}
/**
* Is this task tracker idle?
* @return has this task tracker finished and cleaned up all of its tasks?
*/
public synchronized boolean isIdle() {
return tasks.isEmpty() && tasksToCleanup.isEmpty();
}
/**
* Start the TaskTracker, point toward the indicated JobTracker
*/
public static void main(String argv[]) throws Exception {
StringUtils.startupShutdownMessage(TaskTracker.class, argv, LOG);
if (argv.length != 0) {
System.out.println("usage: TaskTracker");
System.exit(-1);
}
try {
JobConf conf=new JobConf();
// enable the server to track time spent waiting on locks
ReflectionUtils.setContentionTracing
(conf.getBoolean(TT_CONTENTION_TRACKING, false));
new TaskTracker(conf).run();
} catch (Throwable e) {
LOG.error("Can not start task tracker because "+
StringUtils.stringifyException(e));
System.exit(-1);
}
}
/**
* This class is used in TaskTracker's Jetty to serve the map outputs
* to other nodes.
*/
@InterfaceAudience.Private
@InterfaceStability.Unstable
public static class MapOutputServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private static final int MAX_BYTES_TO_READ = 64 * 1024;
@Override
public void doGet(HttpServletRequest request,
HttpServletResponse response
) throws ServletException, IOException {
long start = System.currentTimeMillis();
String mapIds = request.getParameter("map");
String reduceId = request.getParameter("reduce");
String jobId = request.getParameter("job");
LOG.debug("Shuffle started for maps (mapIds=" + mapIds + ") to reduce " +
reduceId);
if (jobId == null) {
throw new IOException("job parameter is required");
}
if (mapIds == null || reduceId == null) {
throw new IOException("map and reduce parameters are required");
}
ServletContext context = getServletContext();
int reduce = Integer.parseInt(reduceId);
DataOutputStream outStream = null;
ShuffleServerMetrics shuffleMetrics =
(ShuffleServerMetrics) context.getAttribute("shuffleServerMetrics");
TaskTracker tracker =
(TaskTracker) context.getAttribute("task.tracker");
verifyRequest(request, response, tracker, jobId);
int numMaps = 0;
try {
shuffleMetrics.serverHandlerBusy();
outStream = new DataOutputStream(response.getOutputStream());
//use the same buffersize as used for reading the data from disk
response.setBufferSize(MAX_BYTES_TO_READ);
JobConf conf = (JobConf) context.getAttribute("conf");
LocalDirAllocator lDirAlloc =
(LocalDirAllocator)context.getAttribute("localDirAllocator");
FileSystem rfs = ((LocalFileSystem)
context.getAttribute("local.file.system")).getRaw();
// Split the map ids, send output for one map at a time
StringTokenizer itr = new StringTokenizer(mapIds, ",");
while(itr.hasMoreTokens()) {
String mapId = itr.nextToken();
++numMaps;
sendMapFile(jobId, mapId, reduce, conf, outStream,
tracker, lDirAlloc, shuffleMetrics, rfs);
}
} catch (IOException ie) {
Log log = (Log) context.getAttribute("log");
String errorMsg = ("getMapOutputs(" + mapIds + "," + reduceId +
") failed");
log.warn(errorMsg, ie);
response.sendError(HttpServletResponse.SC_GONE, errorMsg);
shuffleMetrics.failedOutput();
throw ie;
} finally {
shuffleMetrics.serverHandlerFree();
}
outStream.close();
shuffleMetrics.successOutput();
long timeElapsed = (System.currentTimeMillis()-start);
LOG.info("Shuffled " + numMaps
+ "maps (mapIds=" + mapIds + ") to reduce "
+ reduceId + " in " + timeElapsed + "s");
if (ClientTraceLog.isInfoEnabled()) {
ClientTraceLog.info(String.format(MR_CLIENTTRACE_FORMAT,
request.getLocalAddr() + ":" + request.getLocalPort(),
request.getRemoteAddr() + ":" + request.getRemotePort(),
numMaps, "MAPRED_SHUFFLE", reduceId,
timeElapsed));
}
}
private void sendMapFile(String jobId, String mapId,
int reduce,
Configuration conf,
DataOutputStream outStream,
TaskTracker tracker,
LocalDirAllocator lDirAlloc,
ShuffleServerMetrics shuffleMetrics,
FileSystem localfs
) throws IOException {
LOG.debug("sendMapFile called for " + mapId + " to reduce " + reduce);
// true iff IOException was caused by attempt to access input
boolean isInputException = false;
FSDataInputStream mapOutputIn = null;
byte[] buffer = new byte[MAX_BYTES_TO_READ];
long totalRead = 0;
String userName = null;
synchronized (tracker.runningJobs) {
RunningJob rjob = tracker.runningJobs.get(JobID.forName(jobId));
if (rjob == null) {
throw new IOException("Unknown job " + jobId + "!!");
}
userName = rjob.jobConf.getUser();
}
// Index file
Path indexFileName =
lDirAlloc.getLocalPathToRead(TaskTracker.getIntermediateOutputDir(
userName, jobId, mapId)
+ "/file.out.index", conf);
// Map-output file
Path mapOutputFileName =
lDirAlloc.getLocalPathToRead(TaskTracker.getIntermediateOutputDir(
userName, jobId, mapId)
+ "/file.out", conf);
/**
* Read the index file to get the information about where the map-output
* for the given reducer is available.
*/
IndexRecord info =
tracker.indexCache.getIndexInformation(mapId, reduce, indexFileName);
try {
/**
* Read the data from the single map-output file and
* send it to the reducer.
*/
//open the map-output file
mapOutputIn = localfs.open(mapOutputFileName);
//seek to the correct offset for the reduce
mapOutputIn.seek(info.startOffset);
// write header for each map output
ShuffleHeader header = new ShuffleHeader(mapId, info.partLength,
info.rawLength, reduce);
header.write(outStream);
// read the map-output and stream it out
isInputException = true;
long rem = info.partLength;
if (rem == 0) {
throw new IOException("Illegal partLength of 0 for mapId " + mapId +
" to reduce " + reduce);
}
int len =
mapOutputIn.read(buffer, 0, (int)Math.min(rem, MAX_BYTES_TO_READ));
long now = 0;
while (len >= 0) {
rem -= len;
try {
shuffleMetrics.outputBytes(len);
if (len > 0) {
outStream.write(buffer, 0, len);
} else {
LOG.info("Skipped zero-length read of map " + mapId +
" to reduce " + reduce);
}
} catch (IOException ie) {
isInputException = false;
throw ie;
}
totalRead += len;
if (rem == 0) {
break;
}
len =
mapOutputIn.read(buffer, 0, (int)Math.min(rem, MAX_BYTES_TO_READ));
}
try {
outStream.flush();
} catch (IOException ie) {
isInputException = false;
throw ie;
}
} catch (IOException ie) {
String errorMsg = "error on sending map " + mapId + " to reduce " +
reduce;
if (isInputException) {
tracker.mapOutputLost(TaskAttemptID.forName(mapId), errorMsg +
StringUtils.stringifyException(ie));
}
throw new IOException(errorMsg, ie);
} finally {
if (mapOutputIn != null) {
try {
mapOutputIn.close();
} catch (IOException ioe) {
LOG.info("problem closing map output file", ioe);
}
}
}
LOG.info("Sent out " + totalRead + " bytes to reduce " + reduce +
" from map: " + mapId + " given " + info.partLength + "/" +
info.rawLength);
}
/**
* verify that request has correct HASH for the url
* and also add a field to reply header with hash of the HASH
* @param request
* @param response
* @param jt the job token
* @throws IOException
*/
private void verifyRequest(HttpServletRequest request,
HttpServletResponse response, TaskTracker tracker, String jobId)
throws IOException {
SecretKey tokenSecret = tracker.getJobTokenSecretManager()
.retrieveTokenSecret(jobId);
// string to encrypt
String enc_str = SecureShuffleUtils.buildMsgFrom(request);
// hash from the fetcher
String urlHashStr = request.getHeader(SecureShuffleUtils.HTTP_HEADER_URL_HASH);
if(urlHashStr == null) {
response.sendError(HttpServletResponse.SC_UNAUTHORIZED);
throw new IOException("fetcher cannot be authenticated");
}
int len = urlHashStr.length();
LOG.debug("verifying request. enc_str="+enc_str+"; hash=..."+
urlHashStr.substring(len-len/2, len-1)); // half of the hash for debug
// verify - throws exception
try {
SecureShuffleUtils.verifyReply(urlHashStr, enc_str, tokenSecret);
} catch (IOException ioe) {
response.sendError(HttpServletResponse.SC_UNAUTHORIZED);
throw ioe;
}
// verification passed - encode the reply
String reply = SecureShuffleUtils.generateHash(urlHashStr.getBytes(), tokenSecret);
response.addHeader(SecureShuffleUtils.HTTP_HEADER_REPLY_URL_HASH, reply);
len = reply.length();
LOG.debug("Fetcher request verfied. enc_str="+enc_str+";reply="
+reply.substring(len-len/2, len-1));
}
}
// get the full paths of the directory in all the local disks.
Path[] getLocalFiles(JobConf conf, String subdir) throws IOException{
String[] localDirs = conf.getLocalDirs();
Path[] paths = new Path[localDirs.length];
FileSystem localFs = FileSystem.getLocal(conf);
boolean subdirNeeded = (subdir != null) && (subdir.length() > 0);
for (int i = 0; i < localDirs.length; i++) {
paths[i] = (subdirNeeded) ? new Path(localDirs[i], subdir)
: new Path(localDirs[i]);
paths[i] = paths[i].makeQualified(localFs);
}
return paths;
}
FileSystem getLocalFileSystem(){
return localFs;
}
// only used by tests
void setLocalFileSystem(FileSystem fs){
localFs = fs;
}
int getMaxCurrentMapTasks() {
return maxMapSlots;
}
int getMaxCurrentReduceTasks() {
return maxReduceSlots;
}
//called from unit test
synchronized void setMaxMapSlots(int mapSlots) {
maxMapSlots = mapSlots;
}
//called from unit test
synchronized void setMaxReduceSlots(int reduceSlots) {
maxReduceSlots = reduceSlots;
}
/**
* Is the TaskMemoryManager Enabled on this system?
* @return true if enabled, false otherwise.
*/
public boolean isTaskMemoryManagerEnabled() {
return taskMemoryManagerEnabled;
}
public TaskMemoryManagerThread getTaskMemoryManager() {
return taskMemoryManager;
}
/**
* Normalize the negative values in configuration
*
* @param val
* @return normalized val
*/
private long normalizeMemoryConfigValue(long val) {
if (val < 0) {
val = JobConf.DISABLED_MEMORY_LIMIT;
}
return val;
}
/**
* Memory-related setup
*/
private void initializeMemoryManagement() {
//handling @deprecated
if (fConf.get(MAPRED_TASKTRACKER_VMEM_RESERVED_PROPERTY) != null) {
LOG.warn(
JobConf.deprecatedString(
MAPRED_TASKTRACKER_VMEM_RESERVED_PROPERTY));
}
//handling @deprecated
if (fConf.get(MAPRED_TASKTRACKER_PMEM_RESERVED_PROPERTY) != null) {
LOG.warn(
JobConf.deprecatedString(
MAPRED_TASKTRACKER_PMEM_RESERVED_PROPERTY));
}
//handling @deprecated
if (fConf.get(JobConf.MAPRED_TASK_DEFAULT_MAXVMEM_PROPERTY) != null) {
LOG.warn(
JobConf.deprecatedString(
JobConf.MAPRED_TASK_DEFAULT_MAXVMEM_PROPERTY));
}
//handling @deprecated
if (fConf.get(JobConf.UPPER_LIMIT_ON_TASK_VMEM_PROPERTY) != null) {
LOG.warn(
JobConf.deprecatedString(
JobConf.UPPER_LIMIT_ON_TASK_VMEM_PROPERTY));
}
// Use TT_MEMORY_CALCULATOR_PLUGIN if it is configured.
Class<? extends MemoryCalculatorPlugin> clazz =
fConf.getClass(TT_MEMORY_CALCULATOR_PLUGIN,
null, MemoryCalculatorPlugin.class);
MemoryCalculatorPlugin memoryCalculatorPlugin = (clazz == null ?
null : MemoryCalculatorPlugin.getMemoryCalculatorPlugin(clazz, fConf));
if (memoryCalculatorPlugin != null || resourceCalculatorPlugin != null) {
totalVirtualMemoryOnTT = (memoryCalculatorPlugin == null ?
resourceCalculatorPlugin.getVirtualMemorySize() :
memoryCalculatorPlugin.getVirtualMemorySize());
if (totalVirtualMemoryOnTT <= 0) {
LOG.warn("TaskTracker's totalVmem could not be calculated. "
+ "Setting it to " + JobConf.DISABLED_MEMORY_LIMIT);
totalVirtualMemoryOnTT = JobConf.DISABLED_MEMORY_LIMIT;
}
totalPhysicalMemoryOnTT = (memoryCalculatorPlugin == null ?
resourceCalculatorPlugin.getPhysicalMemorySize() :
memoryCalculatorPlugin.getPhysicalMemorySize());
if (totalPhysicalMemoryOnTT <= 0) {
LOG.warn("TaskTracker's totalPmem could not be calculated. "
+ "Setting it to " + JobConf.DISABLED_MEMORY_LIMIT);
totalPhysicalMemoryOnTT = JobConf.DISABLED_MEMORY_LIMIT;
}
}
mapSlotMemorySizeOnTT =
fConf.getLong(
MAPMEMORY_MB,
JobConf.DISABLED_MEMORY_LIMIT);
reduceSlotSizeMemoryOnTT =
fConf.getLong(
REDUCEMEMORY_MB,
JobConf.DISABLED_MEMORY_LIMIT);
totalMemoryAllottedForTasks =
maxMapSlots * mapSlotMemorySizeOnTT + maxReduceSlots
* reduceSlotSizeMemoryOnTT;
if (totalMemoryAllottedForTasks < 0) {
//adding check for the old keys which might be used by the administrator
//while configuration of the memory monitoring on TT
long memoryAllotedForSlot = fConf.normalizeMemoryConfigValue(
fConf.getLong(JobConf.MAPRED_TASK_DEFAULT_MAXVMEM_PROPERTY,
JobConf.DISABLED_MEMORY_LIMIT));
long limitVmPerTask = fConf.normalizeMemoryConfigValue(
fConf.getLong(JobConf.UPPER_LIMIT_ON_TASK_VMEM_PROPERTY,
JobConf.DISABLED_MEMORY_LIMIT));
if(memoryAllotedForSlot == JobConf.DISABLED_MEMORY_LIMIT) {
totalMemoryAllottedForTasks = JobConf.DISABLED_MEMORY_LIMIT;
} else {
if(memoryAllotedForSlot > limitVmPerTask) {
LOG.info("DefaultMaxVmPerTask is mis-configured. " +
"It shouldn't be greater than task limits");
totalMemoryAllottedForTasks = JobConf.DISABLED_MEMORY_LIMIT;
} else {
totalMemoryAllottedForTasks = (maxMapSlots +
maxReduceSlots) * (memoryAllotedForSlot/(1024 * 1024));
}
}
}
if (totalMemoryAllottedForTasks > totalPhysicalMemoryOnTT) {
LOG.info("totalMemoryAllottedForTasks > totalPhysicalMemoryOnTT."
+ " Thrashing might happen.");
} else if (totalMemoryAllottedForTasks > totalVirtualMemoryOnTT) {
LOG.info("totalMemoryAllottedForTasks > totalVirtualMemoryOnTT."
+ " Thrashing might happen.");
}
reservedPhysicalMemoryOnTT =
fConf.getLong(TTConfig.TT_RESERVED_PHYSCIALMEMORY_MB,
JobConf.DISABLED_MEMORY_LIMIT);
reservedPhysicalMemoryOnTT =
reservedPhysicalMemoryOnTT == JobConf.DISABLED_MEMORY_LIMIT ?
JobConf.DISABLED_MEMORY_LIMIT :
reservedPhysicalMemoryOnTT * 1024 * 1024; // normalize to bytes
// start the taskMemoryManager thread only if enabled
setTaskMemoryManagerEnabledFlag();
if (isTaskMemoryManagerEnabled()) {
taskMemoryManager = new TaskMemoryManagerThread(this);
taskMemoryManager.setDaemon(true);
taskMemoryManager.start();
}
}
void setTaskMemoryManagerEnabledFlag() {
if (!ProcfsBasedProcessTree.isAvailable()) {
LOG.info("ProcessTree implementation is missing on this system. "
+ "TaskMemoryManager is disabled.");
taskMemoryManagerEnabled = false;
return;
}
if (reservedPhysicalMemoryOnTT == JobConf.DISABLED_MEMORY_LIMIT
&& totalMemoryAllottedForTasks == JobConf.DISABLED_MEMORY_LIMIT) {
taskMemoryManagerEnabled = false;
LOG.warn("TaskTracker's totalMemoryAllottedForTasks is -1 and " +
"reserved physical memory is not configured. " +
"TaskMemoryManager is disabled.");
return;
}
taskMemoryManagerEnabled = true;
}
/**
* Clean-up the task that TaskMemoryMangerThread requests to do so.
* @param tid
* @param wasFailure mark the task as failed or killed. 'failed' if true,
* 'killed' otherwise
* @param diagnosticMsg
*/
synchronized void cleanUpOverMemoryTask(TaskAttemptID tid, boolean wasFailure,
String diagnosticMsg) {
TaskInProgress tip = runningTasks.get(tid);
if (tip != null) {
tip.reportDiagnosticInfo(diagnosticMsg);
try {
purgeTask(tip, wasFailure); // Marking it as failed/killed.
} catch (IOException ioe) {
LOG.warn("Couldn't purge the task of " + tid + ". Error : " + ioe);
}
}
}
/**
* Wrapper method used by TaskTracker to check if {@link NodeHealthCheckerService}
* can be started
* @param conf configuration used to check if service can be started
* @return true if service can be started
*/
private boolean shouldStartHealthMonitor(Configuration conf) {
return NodeHealthCheckerService.shouldRun(conf);
}
/**
* Wrapper method used to start {@link NodeHealthCheckerService} for
* Task Tracker
* @param conf Configuration used by the service.
*/
private void startHealthMonitor(Configuration conf) {
healthChecker = new NodeHealthCheckerService(conf);
healthChecker.start();
}
TrackerDistributedCacheManager getTrackerDistributedCacheManager() {
return distributedCacheManager;
}
/**
* Download the job-token file from the FS and save on local fs.
* @param user
* @param jobId
* @param jobConf
* @return the local file system path of the downloaded file.
* @throws IOException
*/
private String localizeJobTokenFile(String user, JobID jobId)
throws IOException {
// check if the tokenJob file is there..
Path skPath = new Path(systemDirectory,
jobId.toString()+"/"+TokenCache.JOB_TOKEN_HDFS_FILE);
FileStatus status = null;
long jobTokenSize = -1;
status = systemFS.getFileStatus(skPath); //throws FileNotFoundException
jobTokenSize = status.getLen();
Path localJobTokenFile =
lDirAlloc.getLocalPathForWrite(getLocalJobTokenFile(user,
jobId.toString()), jobTokenSize, fConf);
String localJobTokenFileStr = localJobTokenFile.toUri().getPath();
LOG.debug("localizingJobTokenFile from sd="+skPath.toUri().getPath() +
" to " + localJobTokenFileStr);
// Download job_token
systemFS.copyToLocalFile(skPath, localJobTokenFile);
return localJobTokenFileStr;
}
TaskTrackerJobACLsManager getJobACLsManager() {
return jobACLsManager;
}
}