public void run() {
try {
TaskAttemptID mapId = new TaskAttemptID(new TaskID(jobId, true, taskId), 0);
LOG.info("Starting task: " + mapId);
mapIds.add(mapId);
MapTask map =
new MapTask(systemJobFile.toString(), mapId, taskId, info.getSplitIndex(), 1);
map.setUser(UserGroupInformation.getCurrentUser().getShortUserName());
TaskRunner.setupChildMapredLocalDirs(map, localConf);
MapOutputFile mapOutput = new MapOutputFile();
mapOutput.setConf(localConf);
mapOutputFiles.put(mapId, mapOutput);
map.setJobFile(localJobFile.toString());
localConf.setUser(map.getUser());
map.localizeConfiguration(localConf);
map.setConf(localConf);
try {
map_tasks.getAndIncrement();
myMetrics.launchMap(mapId);
map.run(localConf, Job.this);
myMetrics.completeMap(mapId);
} finally {
map_tasks.getAndDecrement();
}
LOG.info("Finishing task: " + mapId);
} catch (Throwable e) {
this.storedException = e;
}
}
public Job(JobID jobid, String jobSubmitDir) throws IOException {
this.systemJobDir = new Path(jobSubmitDir);
this.systemJobFile = new Path(systemJobDir, "job.xml");
this.id = jobid;
this.localFs = FileSystem.getLocal(conf);
this.localJobDir = localFs.makeQualified(conf.getLocalPath(jobDir));
this.localJobFile = new Path(this.localJobDir, id + ".xml");
// Manage the distributed cache. If there are files to be copied,
// this will trigger localFile to be re-written again.
this.trackerDistributedCacheManager =
new TrackerDistributedCacheManager(conf, taskController);
this.taskDistributedCacheManager =
trackerDistributedCacheManager.newTaskDistributedCacheManager(jobid, conf);
taskDistributedCacheManager.setupCache(conf, "archive", "archive");
if (DistributedCache.getSymlink(conf)) {
// This is not supported largely because,
// for a Child subprocess, the cwd in LocalJobRunner
// is not a fresh slate, but rather the user's working directory.
// This is further complicated because the logic in
// setupWorkDir only creates symlinks if there's a jarfile
// in the configuration.
LOG.warn("LocalJobRunner does not support " + "symlinking into current working dir.");
}
// Setup the symlinks for the distributed cache.
TaskRunner.setupWorkDir(conf, new File(localJobDir.toUri()).getAbsoluteFile());
// Write out configuration file. Instead of copying it from
// systemJobFile, we re-write it, since setup(), above, may have
// updated it.
OutputStream out = localFs.create(localJobFile);
try {
conf.writeXml(out);
} finally {
out.close();
}
this.job = new JobConf(localJobFile);
// Job (the current object) is a Thread, so we wrap its class loader.
if (!taskDistributedCacheManager.getClassPaths().isEmpty()) {
setContextClassLoader(taskDistributedCacheManager.makeClassLoader(getContextClassLoader()));
}
profile =
new JobProfile(
job.getUser(),
id,
systemJobFile.toString(),
"http://localhost:8080/",
job.getJobName());
status = new JobStatus(id, 0.0f, 0.0f, JobStatus.RUNNING);
jobs.put(id, this);
this.start();
}
@SuppressWarnings("unchecked")
@Override
public void run() {
JobID jobId = profile.getJobID();
JobContext jContext = new JobContextImpl(conf, jobId);
org.apache.hadoop.mapreduce.OutputCommitter outputCommitter = null;
try {
outputCommitter = createOutputCommitter(conf.getUseNewMapper(), jobId, conf);
} catch (Exception e) {
LOG.info("Failed to createOutputCommitter", e);
return;
}
try {
TaskSplitMetaInfo[] taskSplitMetaInfos =
SplitMetaInfoReader.readSplitMetaInfo(jobId, localFs, conf, systemJobDir);
int numReduceTasks = job.getNumReduceTasks();
if (numReduceTasks > 1 || numReduceTasks < 0) {
// we only allow 0 or 1 reducer in local mode
numReduceTasks = 1;
job.setNumReduceTasks(1);
}
outputCommitter.setupJob(jContext);
status.setSetupProgress(1.0f);
Map<TaskAttemptID, MapOutputFile> mapOutputFiles =
Collections.synchronizedMap(new HashMap<TaskAttemptID, MapOutputFile>());
List<MapTaskRunnable> taskRunnables =
getMapTaskRunnables(taskSplitMetaInfos, jobId, mapOutputFiles);
ExecutorService mapService = createMapExecutor(taskRunnables.size());
// Start populating the executor with work units.
// They may begin running immediately (in other threads).
for (Runnable r : taskRunnables) {
mapService.submit(r);
}
try {
mapService.shutdown(); // Instructs queue to drain.
// Wait for tasks to finish; do not use a time-based timeout.
// (See http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6179024)
LOG.info("Waiting for map tasks");
mapService.awaitTermination(Long.MAX_VALUE, TimeUnit.NANOSECONDS);
} catch (InterruptedException ie) {
// Cancel all threads.
mapService.shutdownNow();
throw ie;
}
LOG.info("Map task executor complete.");
// After waiting for the map tasks to complete, if any of these
// have thrown an exception, rethrow it now in the main thread context.
for (MapTaskRunnable r : taskRunnables) {
if (r.storedException != null) {
throw new Exception(r.storedException);
}
}
TaskAttemptID reduceId = new TaskAttemptID(new TaskID(jobId, false, 0), 0);
try {
if (numReduceTasks > 0) {
ReduceTask reduce =
new ReduceTask(systemJobFile.toString(), reduceId, 0, mapIds.size(), 1);
reduce.setUser(UserGroupInformation.getCurrentUser().getShortUserName());
JobConf localConf = new JobConf(job);
localConf.set("mapreduce.jobtracker.address", "local");
TaskRunner.setupChildMapredLocalDirs(reduce, localConf);
// move map output to reduce input
for (int i = 0; i < mapIds.size(); i++) {
if (!this.isInterrupted()) {
TaskAttemptID mapId = mapIds.get(i);
Path mapOut = mapOutputFiles.get(mapId).getOutputFile();
MapOutputFile localOutputFile = new MapOutputFile();
localOutputFile.setConf(localConf);
Path reduceIn =
localOutputFile.getInputFileForWrite(
mapId.getTaskID(), localFs.getFileStatus(mapOut).getLen());
if (!localFs.mkdirs(reduceIn.getParent())) {
throw new IOException(
"Mkdirs failed to create " + reduceIn.getParent().toString());
}
if (!localFs.rename(mapOut, reduceIn))
throw new IOException("Couldn't rename " + mapOut);
} else {
throw new InterruptedException();
}
}
if (!this.isInterrupted()) {
reduce.setJobFile(localJobFile.toString());
localConf.setUser(reduce.getUser());
reduce.localizeConfiguration(localConf);
reduce.setConf(localConf);
reduce_tasks += 1;
myMetrics.launchReduce(reduce.getTaskID());
reduce.run(localConf, this);
myMetrics.completeReduce(reduce.getTaskID());
reduce_tasks -= 1;
} else {
throw new InterruptedException();
}
}
} finally {
for (MapOutputFile output : mapOutputFiles.values()) {
output.removeAll();
}
}
// delete the temporary directory in output directory
outputCommitter.commitJob(jContext);
status.setCleanupProgress(1.0f);
if (killed) {
this.status.setRunState(JobStatus.KILLED);
} else {
this.status.setRunState(JobStatus.SUCCEEDED);
}
JobEndNotifier.localRunnerNotification(job, status);
} catch (Throwable t) {
try {
outputCommitter.abortJob(jContext, org.apache.hadoop.mapreduce.JobStatus.State.FAILED);
} catch (IOException ioe) {
LOG.info("Error cleaning up job:" + id);
}
status.setCleanupProgress(1.0f);
if (killed) {
this.status.setRunState(JobStatus.KILLED);
} else {
this.status.setRunState(JobStatus.FAILED);
}
LOG.warn(id, t);
JobEndNotifier.localRunnerNotification(job, status);
} finally {
try {
fs.delete(systemJobFile.getParent(), true); // delete submit dir
localFs.delete(localJobFile, true); // delete local copy
// Cleanup distributed cache
taskDistributedCacheManager.release();
trackerDistributedCacheManager.purgeCache();
} catch (IOException e) {
LOG.warn("Error cleaning up " + id + ": " + e);
}
}
}