X - The type of the bulk partial solution / solution set and the final output.Y - The type of the feed-back data set (bulk partial solution / workset). For bulk iterations, Y is the
same as Xpublic class IterationHeadPactTask<X,Y,S extends Function,OT> extends AbstractIterativePactTask<S,OT>
PactDriver inside. It will read
the initial input and establish a BlockingBackChannel to the iteration's tail. After successfully processing
the input, it will send EndOfSuperstep events to its outputs. It must also be connected to a
synchronization task and after each superstep, it will wait
until it receives an AllWorkersDoneEvent from the sync, which signals that all other heads have also finished
their iteration. Starting with
the second iteration, the input for the head is the output of the tail, transmitted through the backchannel. Once the
iteration is done, the head
will send a TerminationEvent to all it's connected tasks, signaling them to shutdown.
Assumption on the ordering of the outputs: - The first n output gates write to channels that go to the tasks of the step function. - The next m output gates to to the tasks that consume the final solution. - The last output gate connects to the synchronization task.
isSolutionSetUpdate, isWorksetIteration, isWorksetUpdate, worksetAggregator, worksetBackChannelbroadcastInputIterators, broadcastInputReaders, broadcastInputSerializers, chainedTasks, config, driver, eventualOutputs, inputComparators, inputIterators, inputReaders, inputs, inputSerializers, iterativeBroadcastInputs, iterativeInputs, localStrategies, LOG, output, resettableInputs, running, runtimeUdfContext, stub, tempBarriers, userCodeClassLoader| Constructor and Description |
|---|
IterationHeadPactTask() |
| Modifier and Type | Method and Description |
|---|---|
protected int |
getNumTaskInputs() |
protected void |
initOutputs()
Creates a writer for each output.
|
void |
run() |
brokerKey, cancel, closeLocalStrategiesAndCaches, createRuntimeContext, createSolutionSetUpdateOutputCollector, createWorksetUpdateOutputCollector, createWorksetUpdateOutputCollector, currentIteration, getIterationAggregators, incrementIterationCounter, inFirstIteration, initialize, requestTermination, terminationRequested, verifyEndOfSuperstepStatecancelChainedTasks, closeChainedTasks, closeUserCode, constructLogString, createInputIterator, excludeFromReset, formatLogString, getInput, getInputComparator, getInputSerializer, getIOManager, getLastOutputCollector, getLastTasksConfig, getMemoryManager, getOutputCollector, getOutputCollector, getOwningNepheleTask, getStub, getTaskConfig, getUserCodeClassLoader, initBroadcastInputReaders, initBroadcastInputsSerializers, initInputReaders, initInputsSerializersAndComparators, initLocalStrategies, initOutputs, initOutputWriters, initStub, instantiateUserCode, invoke, logAndThrowException, openChainedTasks, openUserCode, readAndSetBroadcastInput, registerInputOutput, reportAndClearAccumulators, resetAllInputs, setLastOutputCollector, setUserCodeClassLoadergetCurrentNumberOfSubtasks, getEnvironment, getIndexInSubtaskGroup, getJobConfiguration, getTaskConfiguration, setEnvironment, userThreadFinished, userThreadStartedprotected int getNumTaskInputs()
getNumTaskInputs in class RegularPactTask<S extends Function,OT>protected void initOutputs()
throws Exception
RegularPactTaskinitOutputs in class RegularPactTask<S extends Function,OT>ExceptionCopyright © 2014 The Apache Software Foundation. All rights reserved.