org.apache.hadoop.mapreduce.v2.app.speculate

Class NullTaskRuntimesEngine

java.lang.Object

org.apache.hadoop.mapreduce.v2.app.speculate.NullTaskRuntimesEngine

All Implemented Interfaces:

TaskRuntimeEstimator

public class NullTaskRuntimesEngine
extends Object
implements TaskRuntimeEstimator

Constructor Summary

Constructors

Constructor and Description
NullTaskRuntimesEngine()

Method Summary

Modifier and Type	Method and Description
long	attemptEnrolledTime(org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptId attemptID)
void	contextualize(org.apache.hadoop.conf.Configuration conf, AppContext context)
void	enrollAttempt(TaskAttemptStatusUpdateEvent.TaskAttemptStatus status, long timestamp)
long	estimatedNewAttemptRuntime(org.apache.hadoop.mapreduce.v2.api.records.TaskId id) Estimates how long a new attempt on this task will take if we start one now
long	estimatedRuntime(org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptId id) Estimate a task attempt's total runtime.
long	runtimeEstimateVariance(org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptId id) Computes the width of the error band of our estimate of the task runtime as returned by TaskRuntimeEstimator.estimatedRuntime(TaskAttemptId)
long	thresholdRuntime(org.apache.hadoop.mapreduce.v2.api.records.TaskId id) Find a maximum reasonable execution wallclock time.
void	updateAttempt(TaskAttemptStatusUpdateEvent.TaskAttemptStatus status, long timestamp)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.hadoop.mapreduce.v2.app.speculate.TaskRuntimeEstimator

hasStagnatedProgress

Constructor Detail

NullTaskRuntimesEngine

public NullTaskRuntimesEngine()

Method Detail

enrollAttempt

public void enrollAttempt(TaskAttemptStatusUpdateEvent.TaskAttemptStatus status,
                          long timestamp)

Specified by:

enrollAttempt in interface TaskRuntimeEstimator

attemptEnrolledTime

public long attemptEnrolledTime(org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptId attemptID)

Specified by:

attemptEnrolledTime in interface TaskRuntimeEstimator

updateAttempt

public void updateAttempt(TaskAttemptStatusUpdateEvent.TaskAttemptStatus status,
                          long timestamp)

Specified by:

updateAttempt in interface TaskRuntimeEstimator

contextualize

public void contextualize(org.apache.hadoop.conf.Configuration conf,
                          AppContext context)

Specified by:

contextualize in interface TaskRuntimeEstimator

thresholdRuntime

public long thresholdRuntime(org.apache.hadoop.mapreduce.v2.api.records.TaskId id)

Description copied from interface: TaskRuntimeEstimator

Find a maximum reasonable execution wallclock time. Includes the time already elapsed. Find a maximum reasonable execution time. Includes the time already elapsed. If the projected total execution time for this task ever exceeds its reasonable execution time, we may speculate it.

Specified by:

thresholdRuntime in interface TaskRuntimeEstimator

Parameters:

id - the TaskId of the task we are asking about

Returns:

the task's maximum reasonable runtime, or MAX_VALUE if we don't have enough information to rule out any runtime, however long.

estimatedRuntime

public long estimatedRuntime(org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptId id)

Description copied from interface: TaskRuntimeEstimator

Estimate a task attempt's total runtime. Includes the time already elapsed.

Specified by:

estimatedRuntime in interface TaskRuntimeEstimator

Parameters:

id - the TaskAttemptId of the attempt we are asking about

Returns:

our best estimate of the attempt's runtime, or -1 if we don't have enough information yet to produce an estimate.

estimatedNewAttemptRuntime

public long estimatedNewAttemptRuntime(org.apache.hadoop.mapreduce.v2.api.records.TaskId id)

Description copied from interface: TaskRuntimeEstimator

Estimates how long a new attempt on this task will take if we start one now

Specified by:

estimatedNewAttemptRuntime in interface TaskRuntimeEstimator

Parameters:

id - the TaskId of the task we are asking about

Returns:

our best estimate of a new attempt's runtime, or -1 if we don't have enough information yet to produce an estimate.

runtimeEstimateVariance

public long runtimeEstimateVariance(org.apache.hadoop.mapreduce.v2.api.records.TaskAttemptId id)

Description copied from interface: TaskRuntimeEstimator

Computes the width of the error band of our estimate of the task runtime as returned by TaskRuntimeEstimator.estimatedRuntime(TaskAttemptId)

Specified by:

runtimeEstimateVariance in interface TaskRuntimeEstimator

Parameters:

id - the TaskAttemptId of the attempt we are asking about

Returns:

our best estimate of the attempt's runtime, or -1 if we don't have enough information yet to produce an estimate.