org.apache.hadoop.mapred
Interface JobSubmissionProtocol

All Superinterfaces:

VersionedProtocol

All Known Implementing Classes:

JobTracker

public interface JobSubmissionProtocol
extends VersionedProtocol

Protocol that a JobClient and the central JobTracker use to communicate. The JobClient can use these methods to submit a Job for execution, and learn about the current system status.

Field Summary

static long

versionID

Method Summary

ClusterStatus	getClusterStatus() Get the current status of the cluster
String	getFilesystemName() A MapReduce system always operates on a single filesystem.
Counters	getJobCounters(String jobid) Grab the current job counters
JobProfile	getJobProfile(String jobid) Grab a handle to a job that is already known to the JobTracker.
JobStatus	getJobStatus(String jobid) Grab a handle to a job that is already known to the JobTracker.
TaskReport[]	getMapTaskReports(String jobid) Grab a bunch of info on the map tasks that make up the job
String	getNewJobId() Allocate a name for the job.
TaskReport[]	getReduceTaskReports(String jobid) Grab a bunch of info on the reduce tasks that make up the job
TaskCompletionEvent[]	getTaskCompletionEvents(String jobid, int fromEventId, int maxEvents) Get task completion events for the jobid, starting from fromEventId.
String[]	getTaskDiagnostics(String jobId, String tipId, String taskId) Get the diagnostics for a given task in a given job
JobStatus[]	jobsToComplete() Get the jobs that are not completed and not failed
void	killJob(String jobid) Kill the indicated job
boolean	killTask(String taskId, boolean shouldFail) Kill indicated task attempt.
JobStatus	submitJob(String jobName) Submit a Job for execution.

Methods inherited from interface org.apache.hadoop.ipc.VersionedProtocol

getProtocolVersion

Field Detail

versionID

static final long versionID

See Also:

Constant Field Values

Method Detail

getNewJobId

String getNewJobId()
                   throws IOException

Allocate a name for the job.

Returns:

a unique job name for submitting jobs.

Throws:

IOException

submitJob

JobStatus submitJob(String jobName)
                    throws IOException

Submit a Job for execution. Returns the latest profile for that job. The job files should be submitted in system-dir/jobName.

Throws:

IOException

getClusterStatus

ClusterStatus getClusterStatus()
                               throws IOException

Get the current status of the cluster

Returns:

summary of the state of the cluster

Throws:

IOException

killJob

void killJob(String jobid)
             throws IOException

Kill the indicated job

Throws:

IOException

killTask

boolean killTask(String taskId,
                 boolean shouldFail)
                 throws IOException

Kill indicated task attempt.

Parameters:

taskId - the id of the task to kill.

shouldFail - if true the task is failed and added to failed tasks list, otherwise it is just killed, w/o affecting job failure status.

Throws:

IOException

getJobProfile

JobProfile getJobProfile(String jobid)
                         throws IOException

Grab a handle to a job that is already known to the JobTracker.

Returns:

Profile of the job, or null if not found.

Throws:

IOException

getJobStatus

JobStatus getJobStatus(String jobid)
                       throws IOException

Grab a handle to a job that is already known to the JobTracker.

Returns:

Status of the job, or null if not found.

Throws:

IOException

getJobCounters

Counters getJobCounters(String jobid)
                        throws IOException

Grab the current job counters

Throws:

IOException

getMapTaskReports

TaskReport[] getMapTaskReports(String jobid)
                               throws IOException

Grab a bunch of info on the map tasks that make up the job

Throws:

IOException

getReduceTaskReports

TaskReport[] getReduceTaskReports(String jobid)
                                  throws IOException

Grab a bunch of info on the reduce tasks that make up the job

Throws:

IOException

getFilesystemName

String getFilesystemName()
                         throws IOException

A MapReduce system always operates on a single filesystem. This function returns the fs name. ('local' if the localfs; 'addr:port' if dfs). The client can then copy files into the right locations prior to submitting the job.

Throws:

IOException

jobsToComplete

JobStatus[] jobsToComplete()
                           throws IOException

Get the jobs that are not completed and not failed

Returns:

array of JobStatus for the running/to-be-run jobs.

Throws:

IOException

getTaskCompletionEvents

TaskCompletionEvent[] getTaskCompletionEvents(String jobid,
                                              int fromEventId,
                                              int maxEvents)
                                              throws IOException

Get task completion events for the jobid, starting from fromEventId. Returns empty aray if no events are available.

Parameters:

jobid - job id

fromEventId - event id to start from.

maxEvents - the max number of events we want to look at

Returns:

array of task completion events.

Throws:

IOException

getTaskDiagnostics

String[] getTaskDiagnostics(String jobId,
                            String tipId,
                            String taskId)
                            throws IOException

Get the diagnostics for a given task in a given job

Parameters:

jobId - the id of the job

Returns:

an array of the diagnostic messages

Throws:

IOException