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.getJobCacheSubdir() + Path.SEPARATOR + t.getJobID() + Path.SEPARATOR + t.getTaskID() + 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; if (lDirAlloc.ifExists(cachePath, conf)) { localPath = lDirAlloc.getLocalPathToRead(cachePath, conf); } else { 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; if (lDirAlloc.ifExists(cachePath, conf)) { localPath = lDirAlloc.getLocalPathToRead(cachePath, conf); } else { 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/@[email protected] \ // -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 = null; if (tracker.isTaskMemoryManagerEnabled()) { pidFile = lDirAlloc .getLocalPathForWrite( (TaskTracker.getPidFilesSubdir() + Path.SEPARATOR + taskid), this.conf) .toString(); } // 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"); } tracker.reportTaskFinished(t.getTaskID(), false); if (t.isMapTask()) { tracker.addFreeMapSlot(); } else { tracker.addFreeReduceSlot(); } } }