| /** |
| * 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.util; |
| |
| import java.util.Iterator; |
| import java.util.Map; |
| |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.pig.backend.hadoop.executionengine.tez.runtime.PigProcessor; |
| import org.apache.pig.data.DataBag; |
| import org.apache.pig.data.Tuple; |
| import org.apache.pig.data.TupleFactory; |
| import org.apache.pig.impl.builtin.PartitionSkewedKeys; |
| import org.apache.pig.impl.util.Pair; |
| |
| import com.google.common.collect.Maps; |
| |
| public class TezRuntimeUtil { |
| private static final Log LOG = LogFactory.getLog(TezRuntimeUtil.class); |
| public static Map<Object, Pair<Integer, Integer>> readReduceMapFromSample(TupleFactory tf) { |
| Map<Object, Pair<Integer, Integer>> reducerMap = Maps.newHashMap(); |
| Map<String, Object> distMap = null; |
| if (PigProcessor.sampleMap != null) { |
| // We've collected sampleMap in PigProcessor |
| distMap = PigProcessor.sampleMap; |
| } else { |
| LOG.info("Key distribution map is empty"); |
| return reducerMap; |
| } |
| |
| long start = System.currentTimeMillis(); |
| |
| try { |
| reducerMap = Maps.newHashMap(); |
| // The distMap is structured as (key, min, max) where min, max |
| // being the index of the reducers |
| DataBag partitionList = (DataBag) distMap.get(PartitionSkewedKeys.PARTITION_LIST); |
| int totalReducers = Integer.valueOf("" + distMap.get(PartitionSkewedKeys.TOTAL_REDUCERS)); |
| Iterator<Tuple> it = partitionList.iterator(); |
| while (it.hasNext()) { |
| Tuple idxTuple = it.next(); |
| Integer maxIndex = (Integer) idxTuple.get(idxTuple.size() - 1); |
| Integer minIndex = (Integer) idxTuple.get(idxTuple.size() - 2); |
| // Used to replace the maxIndex with the number of reducers |
| if (maxIndex < minIndex) { |
| maxIndex = totalReducers + maxIndex; |
| } |
| |
| Tuple keyT; |
| // if the join is on more than 1 key |
| if (idxTuple.size() > 3) { |
| // remove the last 2 fields of the tuple, i.e: minIndex and maxIndex and store |
| // it in the reducer map |
| Tuple keyTuple = tf.newTuple(); |
| for (int i=0; i < idxTuple.size() - 2; i++) { |
| keyTuple.append(idxTuple.get(i)); |
| } |
| keyT = keyTuple; |
| } else { |
| keyT = tf.newTuple(1); |
| keyT.set(0,idxTuple.get(0)); |
| } |
| // number of reducers |
| Integer cnt = maxIndex - minIndex; |
| // 1 is added to account for the 0 index |
| reducerMap.put(keyT, new Pair<Integer, Integer>(minIndex, cnt)); |
| } |
| } catch (Exception e) { |
| throw new RuntimeException(e); |
| } |
| LOG.info("Initialized reducerMap. Time taken: " + (System.currentTimeMillis() - start)); |
| return reducerMap; |
| } |
| } |