1 /*
2 * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 package org.openjdk.bench.java.lang.foreign;
25
26 import org.openjdk.jmh.annotations.Benchmark;
27 import org.openjdk.jmh.annotations.BenchmarkMode;
28 import org.openjdk.jmh.annotations.Fork;
29 import org.openjdk.jmh.annotations.Measurement;
30 import org.openjdk.jmh.annotations.Mode;
31 import org.openjdk.jmh.annotations.OutputTimeUnit;
32 import org.openjdk.jmh.annotations.Param;
33 import org.openjdk.jmh.annotations.Setup;
34 import org.openjdk.jmh.annotations.State;
35 import org.openjdk.jmh.annotations.TearDown;
36 import org.openjdk.jmh.annotations.Warmup;
37
38 import java.lang.foreign.Arena;
39 import java.lang.foreign.MemorySegment;
40 import java.lang.foreign.ValueLayout;
41 import java.lang.invoke.MethodHandles;
42 import java.lang.invoke.VarHandle;
43 import java.nio.ByteBuffer;
44 import java.nio.LongBuffer;
45 import java.util.concurrent.ThreadLocalRandom;
46 import java.util.concurrent.TimeUnit;
47
48 import static java.lang.foreign.ValueLayout.*;
49 import static java.nio.ByteOrder.BIG_ENDIAN;
50
51 /**
52 * This benchmark creates an array of longs with random contents. The array
53 * is then copied into a byte array (using big endian) using different
54 * methods.
55 */
56 @BenchmarkMode(Mode.AverageTime)
57 @Warmup(iterations = 5, time = 500, timeUnit = TimeUnit.MILLISECONDS)
58 @Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
59 @State(org.openjdk.jmh.annotations.Scope.Thread)
60 @OutputTimeUnit(TimeUnit.NANOSECONDS)
61 @Fork(value = 3, jvmArgsAppend = {"--enable-native-access=ALL-UNNAMED", "--enable-preview"})
62 public class MemorySegmentVsBits {
63
64 public static final VarHandle LONG_ARRAY_VH = MethodHandles.byteArrayViewVarHandle(long[].class, BIG_ENDIAN);
65
66 Arena arena = Arena.ofConfined();
67
68 @Param({"1", "2", "16", "64", "256"})
69 public int size;
70 private long[] longs;
71 private byte[] bytes;
72
73 private ByteBuffer byteBuffer;
74 private LongBuffer longBuffer;
75 private MemorySegment segment;
76 private MemorySegment nativeSegment;
77
78 private static final ValueLayout.OfLong OF_LONG = (JAVA_LONG.order() != BIG_ENDIAN)
79 ? JAVA_LONG.withOrder(BIG_ENDIAN)
80 : JAVA_LONG;
81
82 @Setup
83 public void setup() {
84 longs = ThreadLocalRandom.current().longs(size).toArray();
85 bytes = new byte[size * Long.BYTES];
86 byteBuffer = ByteBuffer.wrap(bytes);
87 longBuffer = byteBuffer.asLongBuffer();
88 segment = MemorySegment.ofArray(bytes);
89 nativeSegment = arena.allocate(size * Long.BYTES);
90 }
91
92 @TearDown
93 public void tearDown() {
94 arena.close();
95 }
96
97 @Benchmark
98 public void bitsEquivalent() {
99 for (int i = 0; i < size; i++) {
100 putLong(bytes, i * Long.BYTES, longs[i]);
101 }
102 }
103 @Benchmark
104 public void byteVarHandle() {
105 for (int i = 0; i < size; i++) {
106 LONG_ARRAY_VH.set(bytes, i * Long.BYTES, longs[i]);
107 }
108 }
109 @Benchmark
110 public void byteBuffer() {
111 for (int i = 0; i < size; i++) {
112 byteBuffer.putLong(i * Long.BYTES, longs[i]);
113 }
114 }
115
116 @Benchmark
117 public void longBuffer() {
118 for (int i = 0; i < size; i++) {
119 longBuffer.put(i, longs[i]);
120 }
121 }
122
123 @Benchmark
124 public void panamaHeap() {
125 for (int i = 0; i < size; i++) {
126 segment.set(JAVA_LONG_UNALIGNED, i * Long.BYTES, longs[i]);
127 }
128 }
129
130 @Benchmark
131 public void panamaNative() {
132 for (int i = 0; i < size; i++) {
133 nativeSegment.set(OF_LONG, i * Long.BYTES, longs[i]);
134 }
135 }
136
137 @Benchmark
138 public void panamaNativeUnaligned() {
139 for (int i = 0; i < size; i++) {
140 nativeSegment.set(JAVA_LONG_UNALIGNED, i * Long.BYTES, longs[i]);
141 }
142 }
143
144 // java.io.Bits is package private
145 static void putLong(byte[] b, int off, long val) {
146 b[off + 7] = (byte) (val);
147 b[off + 6] = (byte) (val >>> 8);
148 b[off + 5] = (byte) (val >>> 16);
149 b[off + 4] = (byte) (val >>> 24);
150 b[off + 3] = (byte) (val >>> 32);
151 b[off + 2] = (byte) (val >>> 40);
152 b[off + 1] = (byte) (val >>> 48);
153 b[off] = (byte) (val >>> 56);
154 }
155
156 }