/*
* Copyright (c) 2014 Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package org.openjdk.bench.java.util.stream;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Param;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import java.util.concurrent.TimeUnit;
import java.util.function.LongBinaryOperator;
import java.util.stream.LongStream;
/**
* Benchmark for checking different reduce schemes.
*/
@BenchmarkMode(Mode.Throughput)
@OutputTimeUnit(TimeUnit.SECONDS)
@State(Scope.Thread)
public class Reducers {
/**
* Implementation notes:
* - parallel version requires thread-safe sink, we use the same for sequential version for better comparison
* - operations are explicit inner classes to untangle unwanted lambda effects
* - the result of applying consecutive operations is the same, in order to have the same number of elements in sink
*/
@Param("100000")
private int size;
private LongBinaryOperator op;
@Setup
public void setup() {
op = new LongBinaryOperator() {
@Override
public long applyAsLong(long l, long r) {
return (l > r) ? l : r;
}
};
}
@Benchmark
public long seq_reduce() {
return LongStream.range(0, size).reduce(op).getAsLong();
}
@Benchmark
public long par_reduce() {
return LongStream.range(0, size).parallel().reduce(op).getAsLong();
}
@Benchmark
public long seq_reduce_base() {
return LongStream.range(0, size).reduce(0L, op);
}
@Benchmark
public long par_reduce_base() {
return LongStream.range(0, size).parallel().reduce(0L, op);
}
}