/**
* This is the typical flow for using the DistributedCache classes.
*
* @throws IOException
* @throws LoginException
*/
public void testManagerFlow() throws IOException, LoginException {
if (!canRun()) {
return;
}
// ****** Imitate JobClient code
// Configures a task/job with both a regular file and a "classpath" file.
Configuration subConf = new Configuration(conf);
String userName = getJobOwnerName();
subConf.set("user.name", userName);
JobID jobid = new JobID("jt", 1);
DistributedCache.addCacheFile(firstCacheFile.toUri(), subConf);
DistributedCache.addFileToClassPath(secondCacheFile, subConf, FileSystem.get(subConf));
TrackerDistributedCacheManager.determineTimestamps(subConf);
TrackerDistributedCacheManager.determineCacheVisibilities(subConf);
// ****** End of imitating JobClient code
Path jobFile = new Path(TEST_ROOT_DIR, "job.xml");
FileOutputStream os = new FileOutputStream(new File(jobFile.toString()));
subConf.writeXml(os);
os.close();
// ****** Imitate TaskRunner code.
TrackerDistributedCacheManager manager =
new TrackerDistributedCacheManager(conf, taskController);
TaskDistributedCacheManager handle = manager.newTaskDistributedCacheManager(jobid, subConf);
assertNull(null, DistributedCache.getLocalCacheFiles(subConf));
File workDir = new File(new Path(TEST_ROOT_DIR, "workdir").toString());
handle.setupCache(
subConf,
TaskTracker.getPublicDistributedCacheDir(),
TaskTracker.getPrivateDistributedCacheDir(userName));
JobLocalizer.downloadPrivateCache(subConf);
// DOESN'T ACTUALLY HAPPEN IN THE TaskRunner (THIS IS A TODO)
// handle.setupPrivateCache(localDirAllocator, TaskTracker
// .getPrivateDistributedCacheDir(userName));
// // ****** End of imitating TaskRunner code
Path[] localCacheFiles = DistributedCache.getLocalCacheFiles(subConf);
assertNotNull(null, localCacheFiles);
assertEquals(2, localCacheFiles.length);
Path cachedFirstFile = localCacheFiles[0];
Path cachedSecondFile = localCacheFiles[1];
assertFileLengthEquals(firstCacheFile, cachedFirstFile);
assertFalse("Paths should be different.", firstCacheFile.equals(cachedFirstFile));
assertEquals(1, handle.getClassPaths().size());
assertEquals(cachedSecondFile.toString(), handle.getClassPaths().get(0));
checkFilePermissions(localCacheFiles);
// Cleanup
handle.release();
manager.purgeCache();
assertFalse(pathToFile(cachedFirstFile).exists());
}
@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);
}
}
}