test/micro/org/openjdk/bench/java/lang/ArrayCopyAlignedLarge.java - master - githubmirror/jdk22

test/micro/org/openjdk/bench/java/lang/ArrayCopyAlignedLarge.java

70 строк2 KB

steveatgh

8310159: Bulk copy with Unsafe::arrayCopy is slower compared to memcpy

27 ноя 2023, 20:35

27 ноя 2023, 20:3582967f4

/*
 * Copyright (c) 2023, 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.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
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;

/**
 * Benchmark measuring aligned System.arraycopy.
 */
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
@State(Scope.Thread)
@Warmup(iterations = 10, time = 1)
@Measurement(iterations = 5, time = 1)
@Fork(value = 3)
public class ArrayCopyAlignedLarge {

    @Param({"100000", "1000000", "2000000", "5000000", "10000000"})
    int length;

    int fromPos, toPos;
    byte[] fromByteArr, toByteArr;

    @Setup
    public void setup() {
        // Both positions aligned
        fromPos = 0;
        toPos = 0;

        fromByteArr = new byte[length];
        toByteArr = new byte[length];
    }

    @Benchmark
    public void testByte() {
        System.arraycopy(fromByteArr, fromPos, toByteArr, toPos, length);
    }
}