jdk-24/test/micro/org/openjdk/bench/java/lang/ObjectHashCode.java
Claes Redestad 7a30c97753 8061281: Microbenchmark suite build support, directory layout and sample benchmarks
8061282: Migrate jmh-jdk-microbenchmarks into the JDK

Co-authored-by: Magnus Ihse Bursie <magnus.ihse.bursie@oracle.com>
Co-authored-by: Erik Joelsson <erik.joelsson@oracle.com>
Co-authored-by: Staffan Friberg <sfriberg@kth.se>
Reviewed-by: ecaspole, mchung, erikj, ihse
2018-11-16 23:39:51 +01:00

83 lines
2.7 KiB
Java

/*
* 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
* 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.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import java.util.concurrent.TimeUnit;
/**
* This benchmark assesses different hashCode strategies in HotSpot
*/
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
public class ObjectHashCode {
@Benchmark
@Fork
public int mode_default() {
return System.identityHashCode(new Object());
}
@Benchmark
@Fork(jvmArgsPrepend = {"-XX:+UnlockExperimentalVMOptions", "-XX:hashCode=0"})
public int mode_0() {
return System.identityHashCode(new Object());
}
@Benchmark
@Fork(jvmArgsPrepend = {"-XX:+UnlockExperimentalVMOptions", "-XX:hashCode=1"})
public int mode_1() {
return System.identityHashCode(new Object());
}
@Benchmark
@Fork(jvmArgsPrepend = {"-XX:+UnlockExperimentalVMOptions", "-XX:hashCode=2"})
public int mode_2() {
return System.identityHashCode(new Object());
}
@Benchmark
@Fork(jvmArgsPrepend = {"-XX:+UnlockExperimentalVMOptions", "-XX:hashCode=3"})
public int mode_3() {
return System.identityHashCode(new Object());
}
@Benchmark
@Fork(jvmArgsPrepend = {"-XX:+UnlockExperimentalVMOptions", "-XX:hashCode=4"})
public int mode_4() {
return System.identityHashCode(new Object());
}
@Benchmark
@Fork(jvmArgsPrepend = {"-XX:+UnlockExperimentalVMOptions", "-XX:hashCode=5"})
public int mode_5() {
return System.identityHashCode(new Object());
}
}