| /* |
| * 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.spark; |
| |
| import org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator; |
| import org.apache.pig.data.Tuple; |
| import org.apache.spark.broadcast.Broadcast; |
| import org.apache.spark.rdd.RDD; |
| |
| import java.util.List; |
| import java.util.concurrent.ConcurrentHashMap; |
| |
| /** |
| * singleton class like PigContext |
| */ |
| public class SparkPigContext { |
| |
| private static SparkPigContext context = null; |
| private static ThreadLocal<Integer> defaultParallelism = null; |
| private static ConcurrentHashMap<String, Broadcast<List<Tuple>>> broadcastedVars = new ConcurrentHashMap() ; |
| |
| public static SparkPigContext get(){ |
| if( context == null){ |
| context = new SparkPigContext(); |
| } |
| return context; |
| } |
| public static int getDefaultParallelism() { |
| return defaultParallelism.get(); |
| } |
| |
| |
| public static int getParallelism(List<RDD<Tuple>> predecessors, |
| PhysicalOperator physicalOperator) { |
| if (defaultParallelism != null) { |
| return getDefaultParallelism(); |
| } |
| |
| int parallelism = physicalOperator.getRequestedParallelism(); |
| if (parallelism <= 0) { |
| //Spark automatically sets the number of "map" tasks to run on each file according to its size (though |
| // you can control it through optional parameters to SparkContext.textFile, etc), and for distributed |
| //"reduce" operations, such as groupByKey and reduceByKey, it uses the largest parent RDD's number of |
| // partitions. |
| int maxParallism = 0; |
| for (int i = 0; i < predecessors.size(); i++) { |
| int tmpParallelism = predecessors.get(i).getNumPartitions(); |
| if (tmpParallelism > maxParallism) { |
| maxParallism = tmpParallelism; |
| } |
| } |
| parallelism = maxParallism; |
| } |
| return parallelism; |
| } |
| |
| public static void setDefaultParallelism(int defaultParallelism) { |
| SparkPigContext.defaultParallelism.set(defaultParallelism); |
| } |
| |
| public static ConcurrentHashMap<String, Broadcast<List<Tuple>>> getBroadcastedVars() { |
| return broadcastedVars; |
| } |
| } |