1 /*
2 * Copyright (c) 2017, 2018, Red Hat, Inc. All rights reserved.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This code is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * version 2 for more details (a copy is included in the LICENSE file that
12 * accompanied this code).
13 *
14 * You should have received a copy of the GNU General Public License version
15 * 2 along with this work; if not, write to the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19 * or visit www.oracle.com if you need additional information or have any
20 * questions.
21 *
22 */
23
24 /*
25 * @test TestStringDedup
26 * @summary Test Shenandoah string deduplication implementation
27 * @key gc
28 *
29 * @run main/othervm -Xmx256m -verbose:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
30 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=passive
31 * -XX:+ShenandoahDegeneratedGC
32 * TestStringDedup
33 *
34 * @run main/othervm -Xmx256m -verbose:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
35 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=passive
36 * -XX:-ShenandoahDegeneratedGC
37 * TestStringDedup
38 */
39
40 /*
41 * @test TestStringDedup
42 * @summary Test Shenandoah string deduplication implementation
43 * @key gc
44 *
45 * @run main/othervm -Xmx256m -verbose:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
46 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=compact
47 * TestStringDedup
48 * @run main/othervm -Xmx256m -verbose:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
49 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive
50 * TestStringDedup
51 *
52 * @run main/othervm -Xmx256m -verbose:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
53 * -XX:+UseShenandoahGC
54 * TestStringDedup
55 *
56 * @run main/othervm -Xmx256m -verbose:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
57 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=compact
58 * TestStringDedup
59 */
60
61 /*
62 * @test TestStringDedup
63 * @summary Test Shenandoah string deduplication implementation
64 * @key gc
65 *
66 * @run main/othervm -Xmx256m -verbose:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
67 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=iu
68 * TestStringDedup
69 *
70 * @run main/othervm -Xmx256m -verbose:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
71 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=iu -XX:ShenandoahGCHeuristics=aggressive
72 * TestStringDedup
73 */
74
75 import java.lang.reflect.*;
76 import java.util.*;
77
78 import sun.misc.*;
79
80 public class TestStringDedup {
81 private static Field valueField;
82 private static Unsafe unsafe;
83
84 private static final int UniqueStrings = 20;
85
86 static {
87 try {
88 Field field = Unsafe.class.getDeclaredField("theUnsafe");
89 field.setAccessible(true);
90 unsafe = (Unsafe) field.get(null);
91
92 valueField = String.class.getDeclaredField("value");
93 valueField.setAccessible(true);
94 } catch (Exception e) {
95 throw new RuntimeException(e);
96 }
97 }
98
99 private static Object getValue(String string) {
100 try {
101 return valueField.get(string);
102 } catch (Exception e) {
103 throw new RuntimeException(e);
104 }
105 }
106
107 static class StringAndId {
108 private String str;
109 private int id;
110
111 public StringAndId(String str, int id) {
112 this.str = str;
113 this.id = id;
114 }
115
116 public String str() {
117 return str;
118 }
119
120 public int id() {
121 return id;
122 }
123 }
124
125 private static void generateStrings(ArrayList<StringAndId> strs, int unique_strs) {
126 Random rn = new Random();
127 for (int u = 0; u < unique_strs; u++) {
128 int n = rn.nextInt() % 10;
129 n = Math.max(n, 2);
130 for (int index = 0; index < n; index++) {
131 strs.add(new StringAndId("Unique String " + u, u));
132 }
133 }
134 }
135
136 private static int verifyDedepString(ArrayList<StringAndId> strs) {
137 HashMap<Object, StringAndId> seen = new HashMap<>();
138 int total = 0;
139 int dedup = 0;
140
141 for (StringAndId item : strs) {
142 total++;
143 StringAndId existing_item = seen.get(getValue(item.str()));
144 if (existing_item == null) {
145 seen.put(getValue(item.str()), item);
146 } else {
147 if (item.id() != existing_item.id() ||
148 !item.str().equals(existing_item.str())) {
149 System.out.println("StringDedup error:");
150 System.out.println("String: " + item.str() + " != " + existing_item.str());
151 throw new RuntimeException("StringDedup Test failed");
152 } else {
153 dedup++;
154 }
155 }
156 }
157 System.out.println("Dedup: " + dedup + "/" + total + " unique: " + (total - dedup));
158 return (total - dedup);
159 }
160
161 public static void main(String[] args) {
162 ArrayList<StringAndId> astrs = new ArrayList<>();
163 generateStrings(astrs, UniqueStrings);
164 System.gc();
165 System.gc();
166 System.gc();
167 System.gc();
168 System.gc();
169
170 if (verifyDedepString(astrs) != UniqueStrings) {
171 // Can not guarantee all strings are deduplicated, there can
172 // still have pending items in queues.
173 System.out.println("Not all strings are deduplicated");
174 }
175 }
176 }