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 TestStringDedupStress
26 * @summary Test Shenandoah string deduplication implementation
27 * @key gc
28 * @requires vm.gc.Shenandoah & !vm.graal.enabled
29 * @library /test/lib
30 * @modules java.base/jdk.internal.misc:open
31 * @modules java.base/java.lang:open
32 * java.management
33 *
34 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
35 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=passive
36 * -XX:+ShenandoahDegeneratedGC
37 * TestStringDedupStress
38 *
39 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
40 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=passive
41 * -XX:-ShenandoahDegeneratedGC
42 * TestStringDedupStress
43 */
44
45 /*
46 * @test TestStringDedupStress
47 * @summary Test Shenandoah string deduplication implementation
48 * @key gc
49 * @requires vm.gc.Shenandoah & !vm.graal.enabled
50 * @library /test/lib
51 * @modules java.base/jdk.internal.misc:open
52 * @modules java.base/java.lang:open
53 * java.management
54 *
55 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
56 * -XX:+UseShenandoahGC
57 * -DtargetStrings=3000000
58 * TestStringDedupStress
59 *
60 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
61 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive
62 * -DtargetStrings=2000000
63 * TestStringDedupStress
64 *
65 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
66 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive
67 * -XX:+ShenandoahOOMDuringEvacALot
68 * -DtargetStrings=2000000
69 * TestStringDedupStress
70 *
71 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
72 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=compact
73 * TestStringDedupStress
74 *
75 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
76 * -XX:+UseShenandoahGC
77 * -XX:ShenandoahUpdateRefsEarly=off
78 * -DtargetStrings=3000000
79 * TestStringDedupStress
80 *
81 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
82 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=compact
83 * -XX:ShenandoahUpdateRefsEarly=off
84 * -DtargetStrings=2000000
85 * TestStringDedupStress
86 *
87 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
88 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive
89 * -XX:ShenandoahUpdateRefsEarly=off
90 * -DtargetStrings=2000000
91 * TestStringDedupStress
92 *
93 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
94 * -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive
95 * -XX:ShenandoahUpdateRefsEarly=off -XX:+ShenandoahOOMDuringEvacALot
96 * -DtargetStrings=2000000
97 * TestStringDedupStress
98 */
99
100 /*
101 * @test TestStringDedupStress
102 * @summary Test Shenandoah string deduplication implementation
103 * @key gc
104 * @requires vm.gc.Shenandoah & !vm.graal.enabled
105 * @library /test/lib
106 * @modules java.base/jdk.internal.misc:open
107 * @modules java.base/java.lang:open
108 * java.management
109 *
110 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
111 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=traversal
112 * TestStringDedupStress
113 *
114 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
115 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=traversal -XX:ShenandoahGCHeuristics=aggressive
116 * -DtargetStrings=2000000
117 * TestStringDedupStress
118 *
119 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
120 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=traversal
121 * -XX:+ShenandoahOOMDuringEvacALot
122 * -DtargetStrings=2000000
123 * TestStringDedupStress
124 *
125 * @run main/othervm -Xmx1g -Xlog:gc+stats -Xlog:gc -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication
126 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=traversal -XX:ShenandoahGCHeuristics=aggressive
127 * -XX:+ShenandoahOOMDuringEvacALot
128 * -DtargetStrings=2000000
129 * TestStringDedupStress
130 */
131
132 import java.lang.management.*;
133 import java.lang.reflect.*;
134 import java.util.*;
135
136 import sun.misc.*;
137
138 public class TestStringDedupStress {
139 private static Field valueField;
140 private static Unsafe unsafe;
141
142 private static final int TARGET_STRINGS = Integer.getInteger("targetStrings", 2_500_000);
143 private static final long MAX_REWRITE_GC_CYCLES = 6;
144 private static final long MAX_REWRITE_TIME = 30*1000; // ms
145
146 private static final int UNIQUE_STRINGS = 20;
147
148 static {
149 try {
150 Field field = Unsafe.class.getDeclaredField("theUnsafe");
151 field.setAccessible(true);
152 unsafe = (Unsafe) field.get(null);
153
154 valueField = String.class.getDeclaredField("value");
155 valueField.setAccessible(true);
156 } catch (Exception e) {
157 throw new RuntimeException(e);
158 }
159 }
160
161 private static Object getValue(String string) {
162 try {
163 return valueField.get(string);
164 } catch (Exception e) {
165 throw new RuntimeException(e);
166 }
167 }
168
169 static class StringAndId {
170 private String str;
171 private int id;
172
173 public StringAndId(String str, int id) {
174 this.str = str;
175 this.id = id;
176 }
177
178 public String str() {
179 return str;
180 }
181
182 public int id() {
183 return id;
184 }
185 }
186
187 // Generate uniqueStrings number of strings
188 private static void generateStrings(ArrayList<StringAndId> strs, int uniqueStrings) {
189 Random rn = new Random();
190 for (int u = 0; u < uniqueStrings; u++) {
191 int n = rn.nextInt(uniqueStrings);
192 strs.add(new StringAndId("Unique String " + n, n));
193 }
194 }
195
196 private static int verifyDedupString(ArrayList<StringAndId> strs) {
197 Map<Object, StringAndId> seen = new HashMap<>(TARGET_STRINGS*2);
198 int total = 0;
199 int dedup = 0;
200
201 for (StringAndId item : strs) {
202 total++;
203 StringAndId existingItem = seen.get(getValue(item.str()));
204 if (existingItem == null) {
205 seen.put(getValue(item.str()), item);
206 } else {
207 if (item.id() != existingItem.id() ||
208 !item.str().equals(existingItem.str())) {
209 System.out.println("StringDedup error:");
210 System.out.println("id: " + item.id() + " != " + existingItem.id());
211 System.out.println("or String: " + item.str() + " != " + existingItem.str());
212 throw new RuntimeException("StringDedup Test failed");
213 } else {
214 dedup++;
215 }
216 }
217 }
218 System.out.println("Dedup: " + dedup + "/" + total + " unique: " + (total - dedup));
219 return (total - dedup);
220 }
221
222 static volatile ArrayList<StringAndId> astrs = new ArrayList<>();
223 static GarbageCollectorMXBean gcCycleMBean;
224
225 public static void main(String[] args) {
226 Random rn = new Random();
227
228 for (GarbageCollectorMXBean bean : ManagementFactory.getGarbageCollectorMXBeans()) {
229 if ("Shenandoah Cycles".equals(bean.getName())) {
230 gcCycleMBean = bean;
231 break;
232 }
233 }
234
235 if (gcCycleMBean == null) {
236 throw new RuntimeException("Can not find Shenandoah GC cycle mbean");
237 }
238
239 // Generate roughly TARGET_STRINGS strings, only UNIQUE_STRINGS are unique
240 int genIters = TARGET_STRINGS / UNIQUE_STRINGS;
241 for (int index = 0; index < genIters; index++) {
242 generateStrings(astrs, UNIQUE_STRINGS);
243 }
244
245 long cycleBeforeRewrite = gcCycleMBean.getCollectionCount();
246 long timeBeforeRewrite = System.currentTimeMillis();
247
248 long loop = 1;
249 while (true) {
250 int arrSize = astrs.size();
251 int index = rn.nextInt(arrSize);
252 StringAndId item = astrs.get(index);
253 int n = rn.nextInt(UNIQUE_STRINGS);
254 item.str = "Unique String " + n;
255 item.id = n;
256
257 if (loop++ % 1000 == 0) {
258 // enough GC cycles for rewritten strings to be deduplicated
259 if (gcCycleMBean.getCollectionCount() - cycleBeforeRewrite >= MAX_REWRITE_GC_CYCLES) {
260 break;
261 }
262
263 // enough time is spent waiting for GC to happen
264 if (System.currentTimeMillis() - timeBeforeRewrite >= MAX_REWRITE_TIME) {
265 break;
266 }
267 }
268 }
269 verifyDedupString(astrs);
270 }
271 }