BlackholeValueBench.java

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package org.openjdk.jmh.benchmarks;

import org.openjdk.jmh.annotations.*;
import org.openjdk.jmh.infra.Blackhole;

import java.util.Random;
import java.util.concurrent.TimeUnit;

@OutputTimeUnit(TimeUnit.NANOSECONDS)
@BenchmarkMode(Mode.AverageTime)
@State(Scope.Thread)
public class BlackholeValueBench {

    // TODO: Revisit Blackhole implementation
    // This benchmark highlights the problem with current consume code,
    // which is sensitive to what value we are going to hit inside.
    // Normally, this is solved with more forks, whereas Blackhole
    // randomizes the value it matches against.

    boolean[] array = new boolean[1000];

    @Setup
    public void setup() {
        Random random = new Random(0);
        for (int i = 0; i < array.length; i++) {
            array[i] = random.nextBoolean();
        }
    }

    @Benchmark
    public void test(Blackhole bh) {
        for (boolean b : array) {
            bh.consume(b);
        }
    }

}