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.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package org.openjdk.bench.java.util.stream.ops.ref;
  24 
  25 import org.openjdk.jmh.annotations.Benchmark;
  26 import org.openjdk.jmh.annotations.BenchmarkMode;
  27 import org.openjdk.jmh.annotations.Mode;
  28 import org.openjdk.jmh.annotations.OutputTimeUnit;
  29 import org.openjdk.jmh.annotations.Param;
  30 import org.openjdk.jmh.annotations.Scope;
  31 import org.openjdk.jmh.annotations.Setup;
  32 import org.openjdk.jmh.annotations.State;
  33 
  34 import java.util.concurrent.TimeUnit;
  35 import java.util.function.BinaryOperator;
  36 import java.util.stream.LongStream;
  37 
  38 /**
  39  * Benchmark for reduce() operation.
  40  */
  41 @BenchmarkMode(Mode.Throughput)
  42 @OutputTimeUnit(TimeUnit.NANOSECONDS)
  43 @State(Scope.Thread)
  44 public class Reduce {
  45 
  46     /**
  47      * Implementation notes:
  48      *   - parallel version requires thread-safe sink, we use the same for sequential version for better comparison
  49      *   - operations are explicit inner classes to untangle unwanted lambda effects
  50      */
  51 
  52     @Param("100000")
  53     private int size;
  54 
  55     private BinaryOperator<Long> op1, op2, op3;
  56 
  57     @Setup
  58     public void setup() {
  59         op1 = new BinaryOperator<Long>() {
  60             @Override
  61             public Long apply(Long l, Long r) {
  62                 return (l > r) ? l : r;
  63             }
  64         };
  65         op2 = new BinaryOperator<Long>() {
  66             @Override
  67             public Long apply(Long l, Long r) {
  68                 return (l > r) ? l : r;
  69             }
  70         };
  71         op3 = new BinaryOperator<Long>() {
  72             @Override
  73             public Long apply(Long l, Long r) {
  74                 return (l > r) ? l : r;
  75             }
  76         };
  77     }
  78 
  79     @Benchmark
  80     public long seq_invoke() {
  81         return LongStream.range(0, size).boxed().reduce(op1).get();
  82     }
  83 
  84     @Benchmark
  85     public long seq_chain_111() {
  86         long l = 0;
  87         l += LongStream.range(0, size).boxed().reduce(op1).get();
  88         l += LongStream.range(0, size).boxed().reduce(op1).get();
  89         l += LongStream.range(0, size).boxed().reduce(op1).get();
  90         return l;
  91     }
  92 
  93     @Benchmark
  94     public long seq_chain_123() {
  95         long l = 0;
  96         l += LongStream.range(0, size).boxed().reduce(op1).get();
  97         l += LongStream.range(0, size).boxed().reduce(op2).get();
  98         l += LongStream.range(0, size).boxed().reduce(op3).get();
  99         return l;
 100     }
 101 
 102     @Benchmark
 103     public long par_invoke() {
 104         return LongStream.range(0, size).parallel().boxed().reduce(op1).get();
 105     }
 106 
 107     @Benchmark
 108     public long par_chain_111() {
 109         long l = 0;
 110         l += LongStream.range(0, size).parallel().boxed().reduce(op1).get();
 111         l += LongStream.range(0, size).parallel().boxed().reduce(op1).get();
 112         l += LongStream.range(0, size).parallel().boxed().reduce(op1).get();
 113         return l;
 114     }
 115 
 116     @Benchmark
 117     public long par_chain_123() {
 118         long l = 0;
 119         l += LongStream.range(0, size).parallel().boxed().reduce(op1).get();
 120         l += LongStream.range(0, size).parallel().boxed().reduce(op2).get();
 121         l += LongStream.range(0, size).parallel().boxed().reduce(op3).get();
 122         return l;
 123     }
 124 
 125 }