| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.flink.batch; |
| |
| import org.apache.flink.api.java.DataSet; |
| import org.apache.flink.api.java.ExecutionEnvironment; |
| import org.apache.flink.api.java.aggregation.Aggregations; |
| import org.apache.flink.api.java.io.DiscardingOutputFormat; |
| import org.apache.flink.api.java.operators.DeltaIteration; |
| import org.apache.flink.api.java.tuple.Tuple2; |
| import org.apache.flink.examples.java.graph.ConnectedComponents; |
| import org.apache.flink.examples.java.graph.util.ConnectedComponentsData; |
| |
| /** |
| * This test starts a cluster with 100 task managers and runs connected components with a |
| * parallelism of 100. |
| */ |
| public class HighParallelismIterationsTestProgram { |
| |
| public static void main(String[] args) throws Exception { |
| ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment(); |
| |
| // read vertex and edge data |
| DataSet<Long> vertices = ConnectedComponentsData.getDefaultVertexDataSet(env).rebalance(); |
| |
| DataSet<Tuple2<Long, Long>> edges = |
| ConnectedComponentsData.getDefaultEdgeDataSet(env) |
| .rebalance() |
| .flatMap(new ConnectedComponents.UndirectEdge()); |
| |
| // assign the initial components (equal to the vertex id) |
| DataSet<Tuple2<Long, Long>> verticesWithInitialId = |
| vertices.map(new ConnectedComponents.DuplicateValue<>()); |
| |
| // open a delta iteration |
| DeltaIteration<Tuple2<Long, Long>, Tuple2<Long, Long>> iteration = |
| verticesWithInitialId.iterateDelta(verticesWithInitialId, 100, 0); |
| |
| // apply the step logic: join with the edges, select the minimum neighbor, |
| // update if the component of the candidate is smaller |
| DataSet<Tuple2<Long, Long>> changes = |
| iteration |
| .getWorkset() |
| .join(edges) |
| .where(0) |
| .equalTo(0) |
| .with(new ConnectedComponents.NeighborWithComponentIDJoin()) |
| .groupBy(0) |
| .aggregate(Aggregations.MIN, 1) |
| .join(iteration.getSolutionSet()) |
| .where(0) |
| .equalTo(0) |
| .with(new ConnectedComponents.ComponentIdFilter()); |
| |
| // close the delta iteration (delta and new workset are identical) |
| DataSet<Tuple2<Long, Long>> result = iteration.closeWith(changes, changes); |
| |
| result.output(new DiscardingOutputFormat<>()); |
| |
| env.execute(); |
| } |
| } |