| /** |
| * 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.mapred; |
| |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.conf.Configured; |
| import org.apache.hadoop.mapreduce.TaskType; |
| |
| /** |
| * A {@link WeightAdjuster} implementation that gives a weight boost to new jobs |
| * for a certain amount of time -- by default, a 3x weight boost for 60 seconds. |
| * This can be used to make shorter jobs finish faster, emulating Shortest Job |
| * First scheduling while not starving long jobs. |
| */ |
| public class NewJobWeightBooster extends Configured implements WeightAdjuster { |
| private static final float DEFAULT_FACTOR = 3; |
| private static final long DEFAULT_DURATION = 5 * 60 * 1000; |
| |
| private float factor; |
| private long duration; |
| |
| public void setConf(Configuration conf) { |
| if (conf != null) { |
| factor = conf.getFloat("mapred.newjobweightbooster.factor", |
| DEFAULT_FACTOR); |
| duration = conf.getLong("mapred.newjobweightbooster.duration", |
| DEFAULT_DURATION); |
| } |
| super.setConf(conf); |
| } |
| |
| public double adjustWeight(JobInProgress job, TaskType taskType, |
| double curWeight) { |
| long start = job.getStartTime(); |
| long now = System.currentTimeMillis(); |
| if (now - start < duration) { |
| return curWeight * factor; |
| } else { |
| return curWeight; |
| } |
| } |
| } |