edu.isi.pegasus.planner.refiner

Class ReduceEdges

java.lang.Object

edu.isi.pegasus.planner.refiner.ReduceEdges

public class ReduceEdges
extends Object

An algorithm to reduce remove edges in the workflow, based on a DFS of a graph and doing least common ancestor tranversals to detect duplicate edges.

Author:

Rajiv Mayani, Karan Vahi

Constructor Summary

Constructors

Constructor and Description
ReduceEdges()

Method Summary

Methods

Modifier and Type	Method and Description
void	assignLevels(Graph workflow, GraphNode root) Prunes redundant edges from the workflow.
private Collection<GraphNode>	findLCA(GraphNode from, GraphNode to) We find LCA of from and to.
ADag	reduce(ADag dag) Prunes redundant edges from the workflow.
Graph	reduce(Graph workflow) Prunes redundant edges from the workflow.
private void	reset(Graph workflow) Resets internal depth and color counters associated with the nodes in the workflow, before doing any graph traversals.

Methods inherited from class java.lang.Object

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

Constructor Detail

ReduceEdges

public ReduceEdges()

Method Detail

reduce

public ADag reduce(ADag dag)

Prunes redundant edges from the workflow. For example if A->B->C and A->D exists, we can delete edge A->D

Parameters:

dag - the workflow

Returns:

reduce

public Graph reduce(Graph workflow)

Prunes redundant edges from the workflow.

Parameters:

workflow -

Returns:

the workflow with non essential edges removed

findLCA

private Collection<GraphNode> findLCA(GraphNode from,
                            GraphNode to)

We find LCA of from and to.

Parameters:

from -

to -

Returns:

the ancestors for which the edge from ancestor to the "to" node that have to be deleted.

assignLevels

public void assignLevels(Graph workflow,
                GraphNode root)

Prunes redundant edges from the workflow.

Parameters:

workflow -

root - the root from which to start to assign the levels

reset

private void reset(Graph workflow)

Resets internal depth and color counters associated with the nodes in the workflow, before doing any graph traversals.

Parameters:

workflow - the workflow