view src/main/java/org/openjdk/gcbench/runtime/cmpxchg/CasBarriersRefSuccess.java @ 90:14c1bb4faa6e

Optimize imports
author shade
date Thu, 23 Nov 2017 15:12:49 +0100
parents 583fef4276f5
children
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/*
 * Copyright (c) 2017, Red Hat Inc. 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package org.openjdk.gcbench.runtime.cmpxchg;

import org.openjdk.jmh.annotations.*;

import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicReference;

@Warmup(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
@Measurement(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
@Fork(1)
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@Threads(1)
@State(Scope.Benchmark)
public class CasBarriersRefSuccess {

    AtomicReference<Object> ai;

    Object t1 = new Object();
    Object t2 = t1;

    @Setup
    public void setup() {
        ai = new AtomicReference<>();
        ai.set(t1);
    }

    @Benchmark
    @CompilerControl(CompilerControl.Mode.DONT_INLINE)
    public void test() {
        ai.compareAndSet(t1, t2);
    }

    /*
        i7 4790K, 4.0 Ghz, Linux x86_64, JDK 9 (Shenandoah, 2016-09-05)

            Benchmark         Mode  Cnt   Score   Error  Units

            # Shenandoah
            CasBarriers.test  avgt   25  16.418 ± 0.029  ns/op

            # G1
            CasBarriers.test  avgt   25  12.545 ± 0.041  ns/op

            # Parallel
            CasBarriers.test  avgt   25  12.526 ± 0.030  ns/op

        Analysis pending.
     */

}