/**
* 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 org.apache.commons.logging.*;
import org.apache.hadoop.fs.*;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.filecache.*;
import org.apache.hadoop.util.*;
import java.io.*;
import java.net.InetSocketAddress;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Vector;
import java.net.URI;
/** Base class that runs a task in a separate process. Tasks are run in a
* separate process in order to isolate the map/reduce system code from bugs in
* user supplied map and reduce functions.
*/
abstract class TaskRunner extends Thread {
public static final Log LOG =
LogFactory.getLog(TaskRunner.class);
volatile boolean killed = false;
private TaskTracker.TaskInProgress tip;
private Task t;
private Object lock = new Object();
private volatile boolean done = false;
private int exitCode = -1;
private boolean exitCodeSet = false;
private TaskTracker tracker;
protected JobConf conf;
JvmManager jvmManager;
/**
* for cleaning up old map outputs
*/
protected MapOutputFile mapOutputFile;
public TaskRunner(TaskTracker.TaskInProgress tip, TaskTracker tracker,
JobConf conf) {
this.tip = tip;
this.t = tip.getTask();
this.tracker = tracker;
this.conf = conf;
this.mapOutputFile = new MapOutputFile(t.getJobID());
this.mapOutputFile.setConf(conf);
this.jvmManager = tracker.getJvmManagerInstance();
}
public Task getTask() { return t; }
public TaskTracker.TaskInProgress getTaskInProgress() { return tip; }
public TaskTracker getTracker() { return tracker; }
/** Called to assemble this task's input. This method is run in the parent
* process before the child is spawned. It should not execute user code,
* only system code. */
public boolean prepare() throws IOException {
return true;
}
/** Called when this task's output is no longer needed.
* This method is run in the parent process after the child exits. It should
* not execute user code, only system code.
*/
public void close() throws IOException {}
private static String stringifyPathArray(Path[] p){
if (p == null){
return null;
}
StringBuffer str = new StringBuffer(p[0].toString());
for (int i = 1; i < p.length; i++){
str.append(",");
str.append(p[i].toString());
}
return str.toString();
}
@Override
public final void run() {
try {
//before preparing the job localize
//all the archives
TaskAttemptID taskid = t.getTaskID();
LocalDirAllocator lDirAlloc = new LocalDirAllocator("mapred.local.dir");
File jobCacheDir = null;
if (conf.getJar() != null) {
jobCacheDir = new File(
new Path(conf.getJar()).getParent().toString());
}
File workDir = new File(lDirAlloc.getLocalPathToRead(
TaskTracker.getLocalTaskDir(
t.getJobID().toString(),
t.getTaskID().toString(),
t.isTaskCleanupTask())
+ Path.SEPARATOR + MRConstants.WORKDIR,
conf). toString());
URI[] archives = DistributedCache.getCacheArchives(conf);
URI[] files = DistributedCache.getCacheFiles(conf);
FileStatus fileStatus;
FileSystem fileSystem;
Path localPath;
String baseDir;
if ((archives != null) || (files != null)) {
if (archives != null) {
String[] archivesTimestamps =
DistributedCache.getArchiveTimestamps(conf);
Path[] p = new Path[archives.length];
for (int i = 0; i < archives.length;i++){
fileSystem = FileSystem.get(archives[i], conf);
fileStatus = fileSystem.getFileStatus(
new Path(archives[i].getPath()));
String cacheId = DistributedCache.makeRelative(archives[i],conf);
String cachePath = TaskTracker.getCacheSubdir() +
Path.SEPARATOR + cacheId;
localPath = lDirAlloc.getLocalPathForWrite(cachePath,
fileStatus.getLen(), conf);
baseDir = localPath.toString().replace(cacheId, "");
p[i] = DistributedCache.getLocalCache(archives[i], conf,
new Path(baseDir),
fileStatus,
true, Long.parseLong(
archivesTimestamps[i]),
new Path(workDir.
getAbsolutePath()),
false);
}
DistributedCache.setLocalArchives(conf, stringifyPathArray(p));
}
if ((files != null)) {
String[] fileTimestamps = DistributedCache.getFileTimestamps(conf);
Path[] p = new Path[files.length];
for (int i = 0; i < files.length;i++){
fileSystem = FileSystem.get(files[i], conf);
fileStatus = fileSystem.getFileStatus(
new Path(files[i].getPath()));
String cacheId = DistributedCache.makeRelative(files[i], conf);
String cachePath = TaskTracker.getCacheSubdir() +
Path.SEPARATOR + cacheId;
localPath = lDirAlloc.getLocalPathForWrite(cachePath,
fileStatus.getLen(), conf);
baseDir = localPath.toString().replace(cacheId, "");
p[i] = DistributedCache.getLocalCache(files[i], conf,
new Path(baseDir),
fileStatus,
false, Long.parseLong(
fileTimestamps[i]),
new Path(workDir.
getAbsolutePath()),
false);
}
DistributedCache.setLocalFiles(conf, stringifyPathArray(p));
}
Path localTaskFile = new Path(t.getJobFile());
FileSystem localFs = FileSystem.getLocal(conf);
localFs.delete(localTaskFile, true);
OutputStream out = localFs.create(localTaskFile);
try {
conf.writeXml(out);
} finally {
out.close();
}
}
if (!prepare()) {
return;
}
String sep = System.getProperty("path.separator");
StringBuffer classPath = new StringBuffer();
// start with same classpath as parent process
classPath.append(System.getProperty("java.class.path"));
classPath.append(sep);
if (!workDir.mkdirs()) {
if (!workDir.isDirectory()) {
LOG.fatal("Mkdirs failed to create " + workDir.toString());
}
}
String jar = conf.getJar();
if (jar != null) {
// if jar exists, it into workDir
File[] libs = new File(jobCacheDir, "lib").listFiles();
if (libs != null) {
for (int i = 0; i < libs.length; i++) {
classPath.append(sep); // add libs from jar to classpath
classPath.append(libs[i]);
}
}
classPath.append(sep);
classPath.append(new File(jobCacheDir, "classes"));
classPath.append(sep);
classPath.append(jobCacheDir);
}
// include the user specified classpath
//archive paths
Path[] archiveClasspaths = DistributedCache.getArchiveClassPaths(conf);
if (archiveClasspaths != null && archives != null) {
Path[] localArchives = DistributedCache
.getLocalCacheArchives(conf);
if (localArchives != null){
for (int i=0;i<archives.length;i++){
for(int j=0;j<archiveClasspaths.length;j++){
if (archives[i].getPath().equals(
archiveClasspaths[j].toString())){
classPath.append(sep);
classPath.append(localArchives[i]
.toString());
}
}
}
}
}
//file paths
Path[] fileClasspaths = DistributedCache.getFileClassPaths(conf);
if (fileClasspaths!=null && files != null) {
Path[] localFiles = DistributedCache
.getLocalCacheFiles(conf);
if (localFiles != null) {
for (int i = 0; i < files.length; i++) {
for (int j = 0; j < fileClasspaths.length; j++) {
if (files[i].getPath().equals(
fileClasspaths[j].toString())) {
classPath.append(sep);
classPath.append(localFiles[i].toString());
}
}
}
}
}
classPath.append(sep);
classPath.append(workDir);
// Build exec child jmv args.
Vector<String> vargs = new Vector<String>(8);
File jvm = // use same jvm as parent
new File(new File(System.getProperty("java.home"), "bin"), "java");
vargs.add(jvm.toString());
// Add child (task) java-vm options.
//
// The following symbols if present in mapred.child.java.opts value are
// replaced:
// + @taskid@ is interpolated with value of TaskID.
// Other occurrences of @ will not be altered.
//
// Example with multiple arguments and substitutions, showing
// jvm GC logging, and start of a passwordless JVM JMX agent so can
// connect with jconsole and the likes to watch child memory, threads
// and get thread dumps.
//
// <property>
// <name>mapred.child.java.opts</name>
// <value>-verbose:gc -Xloggc:/tmp/@taskid@.gc \
// -Dcom.sun.management.jmxremote.authenticate=false \
// -Dcom.sun.management.jmxremote.ssl=false \
// </value>
// </property>
//
String javaOpts = conf.get("mapred.child.java.opts", "-Xmx200m");
javaOpts = javaOpts.replace("@taskid@", taskid.toString());
String [] javaOptsSplit = javaOpts.split(" ");
// Add java.library.path; necessary for loading native libraries.
//
// 1. To support native-hadoop library i.e. libhadoop.so, we add the
// parent processes' java.library.path to the child.
// 2. We also add the 'cwd' of the task to it's java.library.path to help
// users distribute native libraries via the DistributedCache.
// 3. The user can also specify extra paths to be added to the
// java.library.path via mapred.child.java.opts.
//
String libraryPath = System.getProperty("java.library.path");
if (libraryPath == null) {
libraryPath = workDir.getAbsolutePath();
} else {
libraryPath += sep + workDir;
}
boolean hasUserLDPath = false;
for(int i=0; i<javaOptsSplit.length ;i++) {
if(javaOptsSplit[i].startsWith("-Djava.library.path=")) {
javaOptsSplit[i] += sep + libraryPath;
hasUserLDPath = true;
break;
}
}
if(!hasUserLDPath) {
vargs.add("-Djava.library.path=" + libraryPath);
}
for (int i = 0; i < javaOptsSplit.length; i++) {
vargs.add(javaOptsSplit[i]);
}
// add java.io.tmpdir given by mapred.child.tmp
String tmp = conf.get("mapred.child.tmp", "./tmp");
Path tmpDir = new Path(tmp);
// if temp directory path is not absolute
// prepend it with workDir.
if (!tmpDir.isAbsolute()) {
tmpDir = new Path(workDir.toString(), tmp);
}
FileSystem localFs = FileSystem.getLocal(conf);
if (!localFs.mkdirs(tmpDir) && !localFs.getFileStatus(tmpDir).isDir()) {
throw new IOException("Mkdirs failed to create " + tmpDir.toString());
}
vargs.add("-Djava.io.tmpdir=" + tmpDir.toString());
// Add classpath.
vargs.add("-classpath");
vargs.add(classPath.toString());
// Setup the log4j prop
long logSize = TaskLog.getTaskLogLength(conf);
vargs.add("-Dhadoop.log.dir=" +
new File(System.getProperty("hadoop.log.dir")
).getAbsolutePath());
vargs.add("-Dhadoop.root.logger=INFO,TLA");
vargs.add("-Dhadoop.tasklog.taskid=" + taskid);
vargs.add("-Dhadoop.tasklog.totalLogFileSize=" + logSize);
if (conf.getProfileEnabled()) {
if (conf.getProfileTaskRange(t.isMapTask()
).isIncluded(t.getPartition())) {
File prof = TaskLog.getTaskLogFile(taskid, TaskLog.LogName.PROFILE);
vargs.add(String.format(conf.getProfileParams(), prof.toString()));
}
}
// Add main class and its arguments
vargs.add(Child.class.getName()); // main of Child
// pass umbilical address
InetSocketAddress address = tracker.getTaskTrackerReportAddress();
vargs.add(address.getAddress().getHostAddress());
vargs.add(Integer.toString(address.getPort()));
vargs.add(taskid.toString()); // pass task identifier
String pidFile = lDirAlloc.getLocalPathForWrite(
(TaskTracker.getPidFile(t.getJobID().toString(),
taskid.toString(), t.isTaskCleanupTask())),
this.conf).toString();
t.setPidFile(pidFile);
tracker.addToMemoryManager(t.getTaskID(), t.isMapTask(), conf, pidFile);
// set memory limit using ulimit if feasible and necessary ...
String[] ulimitCmd = Shell.getUlimitMemoryCommand(conf);
List<String> setup = null;
if (ulimitCmd != null) {
setup = new ArrayList<String>();
for (String arg : ulimitCmd) {
setup.add(arg);
}
}
// Set up the redirection of the task's stdout and stderr streams
File stdout = TaskLog.getTaskLogFile(taskid, TaskLog.LogName.STDOUT);
File stderr = TaskLog.getTaskLogFile(taskid, TaskLog.LogName.STDERR);
stdout.getParentFile().mkdirs();
tracker.getTaskTrackerInstrumentation().reportTaskLaunch(taskid, stdout, stderr);
Map<String, String> env = new HashMap<String, String>();
StringBuffer ldLibraryPath = new StringBuffer();
ldLibraryPath.append(workDir.toString());
String oldLdLibraryPath = null;
oldLdLibraryPath = System.getenv("LD_LIBRARY_PATH");
if (oldLdLibraryPath != null) {
ldLibraryPath.append(sep);
ldLibraryPath.append(oldLdLibraryPath);
}
env.put("LD_LIBRARY_PATH", ldLibraryPath.toString());
jvmManager.launchJvm(this,
jvmManager.constructJvmEnv(setup,vargs,stdout,stderr,logSize,
workDir, env, pidFile, conf));
synchronized (lock) {
while (!done) {
lock.wait();
}
}
tracker.getTaskTrackerInstrumentation().reportTaskEnd(t.getTaskID());
if (exitCodeSet) {
if (!killed && exitCode != 0) {
if (exitCode == 65) {
tracker.getTaskTrackerInstrumentation().taskFailedPing(t.getTaskID());
}
throw new IOException("Task process exit with nonzero status of " +
exitCode + ".");
}
}
} catch (FSError e) {
LOG.fatal("FSError", e);
try {
tracker.fsError(t.getTaskID(), e.getMessage());
} catch (IOException ie) {
LOG.fatal(t.getTaskID()+" reporting FSError", ie);
}
} catch (Throwable throwable) {
LOG.warn(t.getTaskID()+" Child Error", throwable);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
throwable.printStackTrace(new PrintStream(baos));
try {
tracker.reportDiagnosticInfo(t.getTaskID(), baos.toString());
} catch (IOException e) {
LOG.warn(t.getTaskID()+" Reporting Diagnostics", e);
}
} finally {
try{
URI[] archives = DistributedCache.getCacheArchives(conf);
URI[] files = DistributedCache.getCacheFiles(conf);
if (archives != null){
for (int i = 0; i < archives.length; i++){
DistributedCache.releaseCache(archives[i], conf);
}
}
if (files != null){
for(int i = 0; i < files.length; i++){
DistributedCache.releaseCache(files[i], conf);
}
}
}catch(IOException ie){
LOG.warn("Error releasing caches : Cache files might not have been cleaned up");
}
tip.reportTaskFinished();
}
}
//Mostly for setting up the symlinks. Note that when we setup the distributed
//cache, we didn't create the symlinks. This is done on a per task basis
//by the currently executing task.
public static void setupWorkDir(JobConf conf) throws IOException {
File workDir = new File(".").getAbsoluteFile();
FileUtil.fullyDelete(workDir);
if (DistributedCache.getSymlink(conf)) {
URI[] archives = DistributedCache.getCacheArchives(conf);
URI[] files = DistributedCache.getCacheFiles(conf);
Path[] localArchives = DistributedCache.getLocalCacheArchives(conf);
Path[] localFiles = DistributedCache.getLocalCacheFiles(conf);
if (archives != null) {
for (int i = 0; i < archives.length; i++) {
String link = archives[i].getFragment();
if (link != null) {
link = workDir.toString() + Path.SEPARATOR + link;
File flink = new File(link);
if (!flink.exists()) {
FileUtil.symLink(localArchives[i].toString(), link);
}
}
}
}
if (files != null) {
for (int i = 0; i < files.length; i++) {
String link = files[i].getFragment();
if (link != null) {
link = workDir.toString() + Path.SEPARATOR + link;
File flink = new File(link);
if (!flink.exists()) {
FileUtil.symLink(localFiles[i].toString(), link);
}
}
}
}
}
File jobCacheDir = null;
if (conf.getJar() != null) {
jobCacheDir = new File(
new Path(conf.getJar()).getParent().toString());
}
// create symlinks for all the files in job cache dir in current
// workingdir for streaming
try{
DistributedCache.createAllSymlink(conf, jobCacheDir,
workDir);
} catch(IOException ie){
// Do not exit even if symlinks have not been created.
LOG.warn(StringUtils.stringifyException(ie));
}
// add java.io.tmpdir given by mapred.child.tmp
String tmp = conf.get("mapred.child.tmp", "./tmp");
Path tmpDir = new Path(tmp);
// if temp directory path is not absolute
// prepend it with workDir.
if (!tmpDir.isAbsolute()) {
tmpDir = new Path(workDir.toString(), tmp);
FileSystem localFs = FileSystem.getLocal(conf);
if (!localFs.mkdirs(tmpDir) && !localFs.getFileStatus(tmpDir).isDir()){
throw new IOException("Mkdirs failed to create " + tmpDir.toString());
}
}
}
/**
* Kill the child process
*/
public void kill() {
killed = true;
jvmManager.taskKilled(this);
signalDone();
}
public void signalDone() {
synchronized (lock) {
done = true;
lock.notify();
}
}
public void setExitCode(int exitCode) {
this.exitCodeSet = true;
this.exitCode = exitCode;
}
}