/**
* 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.pig.backend.hadoop.executionengine.tez.runtime;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.tez.dag.api.EdgeManagerPluginDescriptor;
import org.apache.tez.dag.api.InputDescriptor;
import org.apache.tez.dag.api.VertexManagerPlugin;
import org.apache.tez.dag.api.VertexManagerPluginContext;
import org.apache.tez.dag.api.VertexManagerPluginContext.TaskWithLocationHint;
import org.apache.tez.dag.app.dag.impl.ScatterGatherEdgeManager;
import org.apache.tez.runtime.api.Event;
import org.apache.tez.runtime.api.events.VertexManagerEvent;
import com.google.common.collect.Lists;
/**
* VertexManagerPlugin used by sorting job of order by and skewed join.
* What is does is to set parallelism of the sorting vertex
* according to numParallelism specified by the predecessor vertex.
* The complex part is the PigOrderByEdgeManager, which specify how
* partition in the previous setting routes to the new vertex setting
*/
public class PartitionerDefinedVertexManager extends VertexManagerPlugin {
private static final Log LOG = LogFactory.getLog(PartitionerDefinedVertexManager.class);
private boolean isParallelismSet = false;
private int dynamicParallelism = -1;
public PartitionerDefinedVertexManager(VertexManagerPluginContext context) {
super(context);
}
@Override
public void initialize() {
// Nothing to do
}
@Override
public void onRootVertexInitialized(String inputName, InputDescriptor inputDescriptor,
List<Event> events) {
// Nothing to do
}
@Override
public void onSourceTaskCompleted(String srcVertexName, Integer srcTaskId) {
// Nothing to do
}
@Override
public void onVertexManagerEventReceived(VertexManagerEvent vmEvent) {
// There could be multiple partition vertex sending VertexManagerEvent
// Only need to setVertexParallelism once
if (isParallelismSet) {
return;
}
isParallelismSet = true;
// Need to distinguish from VertexManagerEventPayloadProto emitted by OrderedPartitionedKVOutput
if (vmEvent.getUserPayload().limit()==4) {
dynamicParallelism = vmEvent.getUserPayload().getInt();
} else {
return;
}
int currentParallelism = getContext().getVertexNumTasks(getContext().getVertexName());
if (dynamicParallelism != -1) {
if (dynamicParallelism!=currentParallelism) {
LOG.info("Pig Partitioner Defined Vertex Manager: reset parallelism to " + dynamicParallelism
+ " from " + currentParallelism);
Map<String, EdgeManagerPluginDescriptor> edgeManagers =
new HashMap<String, EdgeManagerPluginDescriptor>();
for(String vertex : getContext().getInputVertexEdgeProperties().keySet()) {
EdgeManagerPluginDescriptor edgeManagerDescriptor =
EdgeManagerPluginDescriptor.create(ScatterGatherEdgeManager.class.getName());
edgeManagers.put(vertex, edgeManagerDescriptor);
}
getContext().setVertexParallelism(dynamicParallelism, null, edgeManagers, null);
}
}
}
@Override
public void onVertexStarted(Map<String, List<Integer>> completions) {
if (dynamicParallelism != -1) {
List<TaskWithLocationHint> tasksToStart = Lists.newArrayListWithCapacity(dynamicParallelism);
for (int i=0; i<dynamicParallelism; ++i) {
tasksToStart.add(new TaskWithLocationHint(new Integer(i), null));
}
getContext().scheduleVertexTasks(tasksToStart);
}
}
}