/*
* 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.giraph.integration;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import org.apache.giraph.conf.ImmutableClassesGiraphConfiguration;
import org.apache.giraph.worker.WorkerInfo;
import org.apache.giraph.partition.BasicPartitionOwner;
import org.apache.giraph.partition.HashMasterPartitioner;
import org.apache.giraph.partition.HashPartitionerFactory;
import org.apache.giraph.partition.MasterGraphPartitioner;
import org.apache.giraph.partition.PartitionOwner;
import org.apache.giraph.partition.PartitionStats;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.log4j.Logger;
/**
* Example graph partitioner that builds on {@link HashMasterPartitioner} to
* send the partitions to the worker that matches the superstep. It is for
* testing only and should never be used in practice.
*
* @param <I> Vertex id
* @param <V> Vertex value
* @param <E> Edge value
* @param <M> Message data
*/
@SuppressWarnings("rawtypes")
public class SuperstepHashPartitionerFactory<I extends WritableComparable,
V extends Writable, E extends Writable, M extends Writable>
extends HashPartitionerFactory<I, V, E, M> {
/**
* Changes the {@link HashMasterPartitioner} to make ownership of the
* partitions based on a superstep. For testing only as it is totally
* unbalanced.
*
* @param <I> vertex id
* @param <V> vertex data
* @param <E> edge data
* @param <M> message data
*/
private static class SuperstepMasterPartition<I extends WritableComparable,
V extends Writable, E extends Writable, M extends Writable>
extends HashMasterPartitioner<I, V, E, M> {
/** Class logger */
private static Logger LOG =
Logger.getLogger(SuperstepMasterPartition.class);
/**
* Construction with configuration.
*
* @param conf Configuration to be stored.
*/
public SuperstepMasterPartition(ImmutableClassesGiraphConfiguration conf) {
super(conf);
}
@Override
public Collection<PartitionOwner> generateChangedPartitionOwners(
Collection<PartitionStats> allPartitionStatsList,
Collection<WorkerInfo> availableWorkerInfos,
int maxWorkers,
long superstep) {
// Assign all the partitions to
// superstep mod availableWorkerInfos
// Guaranteed to be different if the workers (and their order)
// do not change
long workerIndex = superstep % availableWorkerInfos.size();
int i = 0;
WorkerInfo chosenWorkerInfo = null;
for (WorkerInfo workerInfo : availableWorkerInfos) {
if (workerIndex == i) {
chosenWorkerInfo = workerInfo;
}
++i;
}
if (LOG.isInfoEnabled()) {
LOG.info("generateChangedPartitionOwners: Chosen worker " +
"for superstep " + superstep + " is " +
chosenWorkerInfo);
}
List<PartitionOwner> partitionOwnerList = new ArrayList<PartitionOwner>();
for (PartitionOwner partitionOwner :
getCurrentPartitionOwners()) {
WorkerInfo prevWorkerinfo =
partitionOwner.getWorkerInfo().equals(chosenWorkerInfo) ?
null : partitionOwner.getWorkerInfo();
PartitionOwner tmpPartitionOwner =
new BasicPartitionOwner(partitionOwner.getPartitionId(),
chosenWorkerInfo,
prevWorkerinfo,
null);
partitionOwnerList.add(tmpPartitionOwner);
LOG.info("partition owner was " + partitionOwner +
", new " + tmpPartitionOwner);
}
setPartitionOwnerList(partitionOwnerList);
return partitionOwnerList;
}
}
@Override
public MasterGraphPartitioner<I, V, E, M>
createMasterGraphPartitioner() {
return new SuperstepMasterPartition<I, V, E, M>(getConf());
}
}