@InterfaceAudience.LimitedPrivate(value="MapReduce") @InterfaceStability.Unstable public class MapTask extends Task
Modifier and Type | Class and Description |
---|---|
static class |
MapTask.MapOutputBuffer<K,V> |
Task.CombineOutputCollector<K,V>, Task.CombinerRunner<K,V>, Task.CombineValuesIterator<KEY,VALUE>, Task.Counter, Task.NewCombinerRunner<K,V>, Task.OldCombinerRunner<K,V>, Task.TaskReporter
Modifier and Type | Field and Description |
---|---|
static int |
MAP_OUTPUT_INDEX_RECORD_LENGTH
The size of each record in the index file for the map-outputs.
|
committer, conf, DEFAULT_MR_COMBINE_RECORDS_BEFORE_PROGRESS, FILESYSTEM_COUNTER_GROUP, jobCleanup, jobContext, jobRunStateForCleanup, jobSetup, jvmContext, lDirAlloc, mapOutputFile, MR_COMBINE_RECORDS_BEFORE_PROGRESS, outputFormat, PROGRESS_INTERVAL, spilledRecordsCounter, taskCleanup, taskContext, tokenSecret, umbilical
Constructor and Description |
---|
MapTask() |
MapTask(java.lang.String jobFile,
TaskAttemptID taskId,
int partition,
JobSplit.TaskSplitIndex splitIndex,
int numSlotsRequired) |
Modifier and Type | Method and Description |
---|---|
org.apache.hadoop.mapred.TaskRunner |
createRunner(TaskTracker tracker,
org.apache.hadoop.mapred.TaskTracker.TaskInProgress tip,
org.apache.hadoop.mapred.TaskTracker.RunningJob rjob)
Return an approprate thread runner for this task.
|
boolean |
isMapTask() |
void |
readFields(java.io.DataInput in) |
void |
run(JobConf job,
TaskUmbilicalProtocol umbilical)
Run this task as a part of the named job.
|
void |
write(java.io.DataOutput out) |
void |
writeFilesRequiredForRerun(JobConf conf)
Write files that the IsolationRunner will need to rerun the task.
|
createReduceContext, done, getConf, getFileSystemCounterNames, getJobFile, getJobID, getJobTokenSecret, getJvmContext, getMapOutputFile, getNumSlotsRequired, getPartition, getPhase, getProgress, getSkipRanges, getTaskID, getUser, initialize, isSkipping, localizeConfiguration, reportFatalError, reportNextRecordRange, runJobCleanupTask, runJobSetupTask, runTaskCleanupTask, setConf, setJobFile, setJobTokenSecret, setJvmContext, setPhase, setSkipping, setSkipRanges, setWriteSkipRecs, statusUpdate, supportIsolationRunner, toString, toWriteSkipRecs
public static final int MAP_OUTPUT_INDEX_RECORD_LENGTH
public MapTask()
public MapTask(java.lang.String jobFile, TaskAttemptID taskId, int partition, JobSplit.TaskSplitIndex splitIndex, int numSlotsRequired)
public void writeFilesRequiredForRerun(JobConf conf) throws java.io.IOException
Task
writeFilesRequiredForRerun
in class Task
java.io.IOException
public org.apache.hadoop.mapred.TaskRunner createRunner(TaskTracker tracker, org.apache.hadoop.mapred.TaskTracker.TaskInProgress tip, org.apache.hadoop.mapred.TaskTracker.RunningJob rjob) throws java.io.IOException
Task
createRunner
in class Task
tip
- TODOjava.io.IOException
public void write(java.io.DataOutput out) throws java.io.IOException
public void readFields(java.io.DataInput in) throws java.io.IOException
readFields
in interface org.apache.hadoop.io.Writable
readFields
in class Task
java.io.IOException
public void run(JobConf job, TaskUmbilicalProtocol umbilical) throws java.io.IOException, java.lang.ClassNotFoundException, java.lang.InterruptedException
Task
Copyright © 2009 The Apache Software Foundation