| /** |
| * 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; |
| |
| /** |
| * |
| * This class is a concrete PeriodicStatsAccumulator that deals with |
| * measurements where the raw data are a measurement of an |
| * accumulation. The result in each bucket is the estimate |
| * of the progress-weighted change in that quantity over the |
| * progress range covered by the bucket. |
| * |
| * <p>An easy-to-understand example of this kind of quantity would be |
| * a distance traveled. It makes sense to consider that portion of |
| * the total travel that can be apportioned to each bucket. |
| * |
| */ |
| class CumulativePeriodicStats extends PeriodicStatsAccumulator { |
| // int's are acceptable here, even though times are normally |
| // long's, because these are a difference and an int won't |
| // overflow for 24 days. Tasks can't run for more than about a |
| // week for other reasons, and most jobs would be written |
| int previousValue = 0; |
| |
| CumulativePeriodicStats(int count) { |
| super(count); |
| } |
| |
| /** |
| * |
| * accumulates a new reading by keeping a running account of the |
| * value distance from the beginning of the bucket to the end of |
| * this reading |
| */ |
| @Override |
| protected void extendInternal(double newProgress, int newValue) { |
| if (state == null) { |
| return; |
| } |
| |
| state.currentAccumulation += (double)(newValue - previousValue); |
| previousValue = newValue; |
| } |
| } |