org.apache.flink.optimizer.plantranslate

Class JobGraphGenerator

java.lang.Object

org.apache.flink.optimizer.plantranslate.JobGraphGenerator

All Implemented Interfaces:

Visitor<PlanNode>

public class JobGraphGenerator
extends Object
implements Visitor<PlanNode>

This component translates the optimizer's resulting OptimizedPlan to a JobGraph. The translation is not strictly a one-to-one, because some nodes from the OptimizedPlan are collapsed into one job vertex.

This translation does not make any decisions or assumptions. All degrees-of-freedom in the execution of the job are made by the Optimizer, so that this translation becomes a deterministic mapping.

The basic method of operation is a top down traversal over the plan graph. On the way down, job vertices are created for the plan nodes, on the way back up, the nodes connect their predecessors.

Field Summary

Fields

Modifier and Type	Field and Description
static String	MERGE_ITERATION_AUX_TASKS_KEY

Constructor Summary

Constructors

Constructor and Description
JobGraphGenerator() Creates a new job graph generator that uses the default values for its resource configuration.
JobGraphGenerator(Configuration config)

Method Summary

Modifier and Type	Method and Description
JobGraph	compileJobGraph(OptimizedPlan program) Translates a OptimizedPlan into a JobGraph.
JobGraph	compileJobGraph(OptimizedPlan program, JobID jobId)
void	postVisit(PlanNode node) This method implements the post-visit during the depth-first traversal.
boolean	preVisit(PlanNode node) This methods implements the pre-visiting during a depth-first traversal.

Methods inherited from class java.lang.Object

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

Field Detail

MERGE_ITERATION_AUX_TASKS_KEY

public static final String MERGE_ITERATION_AUX_TASKS_KEY

See Also:

Constant Field Values

Constructor Detail

JobGraphGenerator

public JobGraphGenerator()

Creates a new job graph generator that uses the default values for its resource configuration.

JobGraphGenerator

public JobGraphGenerator(Configuration config)

Method Detail

compileJobGraph

public JobGraph compileJobGraph(OptimizedPlan program)

Translates a OptimizedPlan into a JobGraph.

Parameters:

program - Optimized plan that is translated into a JobGraph.

Returns:

JobGraph generated from the plan.

compileJobGraph

public JobGraph compileJobGraph(OptimizedPlan program,
                                JobID jobId)

preVisit

public boolean preVisit(PlanNode node)

This methods implements the pre-visiting during a depth-first traversal. It create the job vertex and sets local strategy.

Specified by:

preVisit in interface Visitor<PlanNode>

Parameters:

node - The node that is currently processed.

Returns:

True, if the visitor should descend to the node's children, false if not.

See Also:

Visitor.preVisit(org.apache.flink.util.Visitable)

postVisit

public void postVisit(PlanNode node)

This method implements the post-visit during the depth-first traversal. When the post visit happens, all of the descendants have been processed, so this method connects all of the current node's predecessors to the current node.

Specified by:

postVisit in interface Visitor<PlanNode>

Parameters:

node - The node currently processed during the post-visit.

See Also:

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