1 /*
   2  * Copyright (c) 2014 Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package org.openjdk.bench.java.util.stream.tasks.IntegerSum;
  26 
  27 import org.openjdk.jmh.annotations.Benchmark;
  28 import org.openjdk.jmh.annotations.BenchmarkMode;
  29 import org.openjdk.jmh.annotations.Level;
  30 import org.openjdk.jmh.annotations.Mode;
  31 import org.openjdk.jmh.annotations.OutputTimeUnit;
  32 import org.openjdk.jmh.annotations.Scope;
  33 import org.openjdk.jmh.annotations.Setup;
  34 import org.openjdk.jmh.annotations.State;
  35 
  36 import java.util.Arrays;
  37 import java.util.concurrent.RecursiveTask;
  38 import java.util.concurrent.TimeUnit;
  39 import java.util.function.BinaryOperator;
  40 
  41 /**
  42  * Bulk scenario: compute the sum of Integer array.
  43  *
  44  * This test covers bulk infrastructure only. Refer to other tests for lambda-specific cases.
  45  */
  46 @BenchmarkMode(Mode.Throughput)
  47 @OutputTimeUnit(TimeUnit.SECONDS)
  48 @State(Scope.Benchmark)
  49 public class Bulk {
  50 
  51     private IntegerSumProblem problem;
  52 
  53     @Setup(Level.Trial)
  54     public void populateData(){
  55         problem = new IntegerSumProblem();
  56     }
  57 
  58     @Benchmark
  59     public int hm_seq() {
  60         int sum = 0;
  61         for (int v : problem.get()) {
  62             sum += v;
  63         }
  64         return sum;
  65     }
  66 
  67     @Benchmark
  68     public int hm_par() {
  69         return new SumIntTask(problem.get()).invoke();
  70     }
  71 
  72     @Benchmark
  73     public int bulk_seq_inner() {
  74         return Arrays.stream(problem.get()).reduce(0, new BinaryOperator<Integer>() {
  75             @Override
  76             public Integer apply(Integer left, Integer right) {
  77                 return left + right;
  78             }
  79         });
  80     }
  81 
  82     @Benchmark
  83     public int bulk_par_inner() {
  84         return Arrays.stream(problem.get()).parallel().reduce(0, new BinaryOperator<Integer>() {
  85             @Override
  86             public Integer apply(Integer left, Integer right) {
  87                 return left + right;
  88             }
  89         });
  90     }
  91 
  92     static class SumIntTask extends RecursiveTask<Integer> {
  93         private static final int FORK_LIMIT = 1000;
  94         final Integer[] data;
  95         final int start, end;
  96 
  97         SumIntTask(Integer[] data) {
  98             this(data, 0, data.length);
  99         }
 100 
 101         SumIntTask(Integer[] data, int start, int end) {
 102             this.data = data;
 103             this.start = start;
 104             this.end = end;
 105         }
 106 
 107         @Override
 108         protected Integer compute() {
 109             int size = end - start;
 110             if (size > FORK_LIMIT) {
 111                 int mid = start + size / 2;
 112                 SumIntTask t1 = new SumIntTask(data, start, mid);
 113                 SumIntTask t2 = new SumIntTask(data, mid, end);
 114                 t1.fork();
 115                 return t2.invoke() + t1.join();
 116             } else {
 117                 int sum = 0;
 118                 for (int i = start; i < end; i++) {
 119                     sum += data[i];
 120                 }
 121                 return sum;
 122             }
 123         }
 124     }
 125 
 126 }