jdk-24/test/micro/org/openjdk/bench/java/lang/ThreadOnSpinWaitSharedCounter.java
2022-06-07 07:23:30 +00:00

95 lines
2.9 KiB
Java

/*
* Copyright (c) 2021, 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.
*
* 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.bench.java.lang;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Level;
import org.openjdk.jmh.annotations.Measurement;
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 org.openjdk.jmh.annotations.Warmup;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.MILLISECONDS)
@State(Scope.Benchmark)
@Warmup(iterations = 5, time = 1)
@Measurement(iterations = 5, time = 1)
@Fork(value = 3)
public class ThreadOnSpinWaitSharedCounter {
@Param({"1000000"})
public int maxNum;
@Param({"4"})
public int threadCount;
AtomicInteger theCounter;
Thread threads[];
void work() {
for (;;) {
int prev = theCounter.get();
if (prev >= maxNum) {
break;
}
if (theCounter.compareAndExchange(prev, prev + 1) != prev) {
Thread.onSpinWait();
}
}
}
@Setup(Level.Trial)
public void foo() {
theCounter = new AtomicInteger();
}
@Setup(Level.Invocation)
public void setup() {
theCounter.set(0);
threads = new Thread[threadCount];
for (int i = 0; i < threads.length; i++) {
threads[i] = new Thread(this::work);
}
}
@Benchmark
public void trial() throws Exception {
for (int i = 0; i < threads.length; i++) {
threads[i].start();
}
for (int i = 0; i < threads.length; i++) {
threads[i].join();
}
}
}