Package org.apache.flink.runtime.iterative.task

Class IterationTailTask<S extends org.apache.flink.api.common.functions.Function,OT>

java.lang.Object

org.apache.flink.runtime.jobgraph.tasks.AbstractInvokable

org.apache.flink.runtime.operators.BatchTask<S,OT>

org.apache.flink.runtime.iterative.task.AbstractIterativeTask<S,OT>

org.apache.flink.runtime.iterative.task.IterationTailTask<S,OT>

All Implemented Interfaces:

Terminable, CheckpointableTask, CoordinatedTask, TaskInvokable, TaskContext<S,OT>

public class IterationTailTask<S extends org.apache.flink.api.common.functions.Function,OT>
extends AbstractIterativeTask<S,OT>

An iteration tail, which runs a driver inside.

If the iteration state is updated, the output of this task will be send back to the IterationHeadTask via a BackChannel for the workset -OR- a HashTable for the solution set. Therefore this task must be scheduled on the same instance as the head. It's also possible for the tail to update *both* the workset and the solution set.

If there is a separate solution set tail, the iteration head has to make sure to wait for it to finish.

Field Summary

Fields inherited from class org.apache.flink.runtime.iterative.task.AbstractIterativeTask

isSolutionSetUpdate, isWorksetIteration, isWorksetUpdate, worksetAggregator, worksetBackChannel

Fields inherited from class org.apache.flink.runtime.operators.BatchTask

accumulatorMap, broadcastInputReaders, broadcastInputSerializers, chainedTasks, config, driver, eventualOutputs, inputComparators, inputIterators, inputReaders, inputs, inputSerializers, iterativeBroadcastInputs, iterativeInputs, localStrategies, LOG, output, resettableInputs, running, runtimeUdfContext, stub, tempBarriers

Constructor Summary

Constructors

Constructor	Description
IterationTailTask(Environment environment)	Create an Invokable task and set its environment.

Method Summary

Modifier and Type	Method	Description
protected void	initialize()
void	run()

Methods inherited from class org.apache.flink.runtime.iterative.task.AbstractIterativeTask

brokerKey, cancel, closeLocalStrategiesAndCaches, createRuntimeContext, createSolutionSetUpdateOutputCollector, createWorksetUpdateOutputCollector, createWorksetUpdateOutputCollector, currentIteration, getIterationAggregators, incrementIterationCounter, inFirstIteration, requestTermination, terminationRequested, verifyEndOfSuperstepState

Methods inherited from class org.apache.flink.runtime.operators.BatchTask

cancelChainedTasks, clearReaders, clearWriters, closeChainedTasks, closeUserCode, constructLogString, createInputIterator, excludeFromReset, formatLogString, getContainingTask, getDriverComparator, getInput, getInputSerializer, getIOManager, getLastOutputCollector, getLastTasksConfig, getMemoryManager, getMetricGroup, getNumTaskInputs, getOutputCollector, getOutputCollector, getStub, getTaskConfig, getTaskManagerInfo, initBroadcastInputReaders, initBroadcastInputsSerializers, initInputReaders, initInputsSerializersAndComparators, initLocalStrategies, initOutputs, initOutputs, initStub, instantiateUserCode, invoke, logAndThrowException, openChainedTasks, openUserCode, readAndSetBroadcastInput, releaseBroadcastVariables, resetAllInputs, setLastOutputCollector

Methods inherited from class org.apache.flink.runtime.jobgraph.tasks.AbstractInvokable

abortCheckpointOnBarrier, cleanUp, dispatchOperatorEvent, getCurrentNumberOfSubtasks, getEnvironment, getExecutionConfig, getIndexInSubtaskGroup, getJobConfiguration, getTaskConfiguration, getUserCodeClassLoader, isUsingNonBlockingInput, maybeInterruptOnCancel, notifyCheckpointAbortAsync, notifyCheckpointCompleteAsync, notifyCheckpointSubsumedAsync, restore, triggerCheckpointAsync, triggerCheckpointOnBarrier

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.flink.runtime.operators.TaskContext

getExecutionConfig, getUserCodeClassLoader

Constructor Details

IterationTailTask

public IterationTailTask(Environment environment)

Create an Invokable task and set its environment.

Parameters:

environment - The environment assigned to this invokable.

Method Details

initialize

protected void initialize()
                   throws Exception

Overrides:

initialize in class AbstractIterativeTask<S extends org.apache.flink.api.common.functions.Function,OT>

Throws:

Exception

run

public void run()
         throws Exception

Overrides:

run in class AbstractIterativeTask<S extends org.apache.flink.api.common.functions.Function,OT>

Throws:

Exception