RoundTripLatencyBench.java

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package org.openjdk.jmh.benchmarks;

import org.openjdk.jmh.validation.SpinWaitSupport;
import org.openjdk.jmh.annotations.*;
import org.openjdk.jmh.validation.AffinitySupport;

import java.util.concurrent.TimeUnit;

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

    static final boolean SPINWAIT = Boolean.getBoolean("spinWait");

    @Param("-1")
    int p;

    @Param("-1")
    int c;

    Thread t;

    volatile boolean ping;

    @Setup
    public void setup() {
        if (c != -1) AffinitySupport.bind(c);
        t = new Thread(() -> {
            if (p != -1) AffinitySupport.bind(p);
            Thread t = Thread.currentThread();
            while (!t.isInterrupted()) {
                while (!ping) {
                    if (SPINWAIT) SpinWaitSupport.onSpinWait();
                }
                ping = false;
            }
        });
        t.start();
    }

    @TearDown
    public void tearDown() throws InterruptedException {
        t.interrupt();
        ping = true;
        t.join();
    }

    @Benchmark
    public void test() {
        ping = true;
        while (ping) {
            if (SPINWAIT) SpinWaitSupport.onSpinWait();
        }
    }
}