org.apache.hadoop.hive.ql.optimizer.physical.StageIDsRearranger Maven / Gradle / Ivy
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* 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.hadoop.hive.ql.optimizer.physical;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Queue;
import java.util.Set;
import java.util.concurrent.ConcurrentLinkedQueue;
import org.apache.hadoop.hive.conf.HiveConf;
import org.apache.hadoop.hive.ql.exec.ConditionalTask;
import org.apache.hadoop.hive.ql.exec.Task;
import org.apache.hadoop.hive.ql.parse.SemanticException;
/**
* Simple renumbering of stage ids
*/
public class StageIDsRearranger implements PhysicalPlanResolver {
private static final String PREFIX = "Stage-";
enum ArrangeType {
NONE, IDONLY, TRAVERSE, EXECUTION
}
@Override
public PhysicalContext resolve(PhysicalContext pctx) throws SemanticException {
int counter = 0;
for (Task task : getExplainOrder(pctx)) {
task.setId(PREFIX + (++counter));
}
return null;
}
private static List getExplainOrder(PhysicalContext pctx) {
List tasks = getExplainOrder(pctx.getConf(), pctx.getRootTasks());
if (pctx.getFetchTask() != null) {
tasks.add(pctx.getFetchTask());
}
return tasks;
}
public static List getFetchSources(List> tasks) {
final List sources = new ArrayList();
TaskTraverse traverse = new TaskTraverse() {
@Override
protected void accepted(Task task) {
if (task.getNumChild() == 0 && task.isFetchSource()) {
sources.add(task);
}
}
};
for (Task task : tasks) {
traverse.traverse(task);
}
return sources;
}
public static List getExplainOrder(HiveConf conf, List> tasks) {
for (Task task : tasks) {
task.setRootTask(true);
}
String var = conf.getVar(HiveConf.ConfVars.HIVESTAGEIDREARRANGE);
ArrangeType type = ArrangeType.valueOf(var.toUpperCase());
if (type == ArrangeType.EXECUTION) {
return executionOrder(tasks);
}
return traverseOrder(type, tasks);
}
private static List executionOrder(List> tasks) {
final Queue> queue = new ConcurrentLinkedQueue>(tasks);
TaskTraverse traverse = new TaskTraverse() {
@Override
protected void accepted(Task task) {
List> childTasks = getChildTasks(task);
if (childTasks != null && !childTasks.isEmpty()) {
queue.addAll(childTasks);
}
}
@Override
protected void rejected(Task child) {
queue.add(child);
}
@Override
protected List> next(Task task) {
return queue.isEmpty() ? null : Arrays.>asList(queue.remove());
}
};
if (!queue.isEmpty()) {
traverse.traverse(queue.remove());
}
return new ArrayList(traverse.traversed);
}
static List traverseOrder(final ArrangeType type, List> tasks) {
TaskTraverse traverse = new TaskTraverse() {
@Override
protected boolean isReady(Task task) {
return type == ArrangeType.NONE || type == ArrangeType.IDONLY || super.isReady(task);
}
};
for (Task task : tasks) {
traverse.traverse(task);
}
return new ArrayList(traverse.traversed);
}
public static abstract class TaskTraverse {
protected final Set> traversed = new LinkedHashSet>();
public void traverse(Task task) {
if (traversed.add(task)) {
accepted(task);
}
List> children = next(task);
if (children != null && !children.isEmpty()) {
for (Task child : children) {
if (isReady(child)) {
traverse(child);
} else {
rejected(child);
}
}
}
}
protected boolean isReady(Task task) {
return task.getParentTasks() == null || traversed.containsAll(task.getParentTasks());
}
protected void accepted(Task task) {
}
protected void rejected(Task child) {
}
protected List> next(Task task) {
return getChildTasks(task);
}
protected List> getChildTasks(Task task) {
if (task instanceof ConditionalTask) {
return ((ConditionalTask) task).getListTasks();
}
return task.getChildTasks();
}
}
}