@InterfaceAudience.Private @InterfaceStability.Unstable public class ReduceTask extends Task
Task.CombineOutputCollector<K,V>, Task.CombinerRunner<K,V>, Task.CombineValuesIterator<KEY,VALUE>, Task.Counter, Task.NewCombinerRunner<K,V>, Task.OldCombinerRunner<K,V>, Task.TaskReportercommitter, conf, DEFAULT_COMBINE_RECORDS_BEFORE_PROGRESS, extraData, failedShuffleCounter, FILESYSTEM_COUNTER_GROUP, gcUpdater, jobCleanup, jobContext, jobRunStateForCleanup, jobSetup, lDirAlloc, mapOutputFile, MERGED_OUTPUT_PREFIX, mergedMapOutputsCounter, outputFormat, shuffleSecret, spilledRecordsCounter, taskCleanup, taskContext, tokenSecret, umbilical| Constructor and Description |
|---|
ReduceTask() |
ReduceTask(String jobFile,
TaskAttemptID taskId,
int partition,
int numMaps,
int numSlotsRequired) |
| Modifier and Type | Method and Description |
|---|---|
int |
getNumMaps() |
boolean |
isMapTask() |
void |
localizeConfiguration(JobConf conf)
Localize the given JobConf to be specific for this task.
|
void |
readFields(DataInput in) |
void |
run(JobConf job,
TaskUmbilicalProtocol umbilical)
Run this task as a part of the named job.
|
void |
setLocalMapFiles(Map<TaskAttemptID,MapOutputFile> mapFiles)
Register the set of mapper outputs created by a LocalJobRunner-based
job with this ReduceTask so it knows where to fetch from.
|
void |
write(DataOutput out) |
createReduceContext, done, getConf, getEncryptedSpillKey, getFileSystemCounterNames, getFsStatistics, getJobFile, getJobID, getJobTokenSecret, getMapOutputFile, getNumSlotsRequired, getPartition, getPhase, getProgress, getShuffleSecret, getSkipRanges, getTaskID, initialize, isSkipping, keepTaskFiles, normalizeStatus, reportFatalError, reportNextRecordRange, runJobCleanupTask, runJobSetupTask, runTaskCleanupTask, setConf, setEncryptedSpillKey, setJobFile, setJobTokenSecret, setPhase, setShuffleSecret, setSkipping, setSkipRanges, setWriteSkipRecs, statusUpdate, toString, toWriteSkipRecspublic ReduceTask()
public ReduceTask(String jobFile, TaskAttemptID taskId, int partition, int numMaps, int numSlotsRequired)
public void setLocalMapFiles(Map<TaskAttemptID,MapOutputFile> mapFiles)
public int getNumMaps()
public void localizeConfiguration(JobConf conf) throws IOException
localizeConfiguration in class TaskIOExceptionpublic void write(DataOutput out) throws IOException
write in interface org.apache.hadoop.io.Writablewrite in class TaskIOExceptionpublic void readFields(DataInput in) throws IOException
readFields in interface org.apache.hadoop.io.WritablereadFields in class TaskIOExceptionpublic void run(JobConf job, TaskUmbilicalProtocol umbilical) throws IOException, InterruptedException, ClassNotFoundException
Taskrun in class Taskumbilical - for progress reportsIOExceptionInterruptedExceptionClassNotFoundExceptionCopyright © 2008–2022 Apache Software Foundation. All rights reserved.