1 /*
2 * Copyright (c) 2017, 2018 Red Hat, Inc. and/or its affiliates.
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 TestShenandoahStringDedup.java
26 * @summary Test Shenandoah string deduplication implementation
27 * @key gc
28 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
29 * -DtargetStrings=3000000
30 * ShenandoahStrDedupStress
31 *
32 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
33 * -XX:ShenandoahGCHeuristics=aggressive -DtargetStrings=2000000
34 * ShenandoahStrDedupStress
35 *
36 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
37 * -XX:ShenandoahGCHeuristics=aggressive -XX:+ShenandoahOOMDuringEvacALot -DtargetStrings=2000000
38 * ShenandoahStrDedupStress
39 *
40 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
41 * -XX:ShenandoahGCHeuristics=static -DtargetStrings=4000000
42 * ShenandoahStrDedupStress
43 *
44 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
45 * -XX:ShenandoahGCHeuristics=compact
46 * ShenandoahStrDedupStress
47 *
48 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx1024M
49 * -XX:ShenandoahGCHeuristics=passive -XX:+ShenandoahDegeneratedGC -DtargetOverwrites=40000000
50 * ShenandoahStrDedupStress
51 *
52 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx1024M
53 * -XX:ShenandoahGCHeuristics=passive -XX:-ShenandoahDegeneratedGC -DtargetOverwrites=40000000
54 * ShenandoahStrDedupStress
55 *
56 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
57 * -XX:ShenandoahUpdateRefsEarly=off -DtargetStrings=3000000
58 * ShenandoahStrDedupStress
59 *
60 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
61 * -XX:ShenandoahGCHeuristics=compact -XX:ShenandoahUpdateRefsEarly=off -DtargetStrings=2000000
62 * ShenandoahStrDedupStress
63 *
64 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
65 * -XX:ShenandoahGCHeuristics=aggressive -XX:ShenandoahUpdateRefsEarly=off -DtargetStrings=2000000
66 * ShenandoahStrDedupStress
67 *
68 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
69 * -XX:ShenandoahGCHeuristics=static -XX:ShenandoahUpdateRefsEarly=off -DtargetOverwrites=4000000
70 * ShenandoahStrDedupStress
71 *
72 * @run main/othervm -XX:+UseShenandoahGC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseStringDeduplication -Xmx512M
73 * -XX:ShenandoahGCHeuristics=aggressive -XX:ShenandoahUpdateRefsEarly=off -XX:+ShenandoahOOMDuringEvacALot -DtargetStrings=2000000
74 * ShenandoahStrDedupStress
75 */
76
77 import java.lang.reflect.*;
78 import java.util.*;
79 import sun.misc.*;
80
81 public class ShenandoahStrDedupStress {
82 private static Field valueField;
83 private static Unsafe unsafe;
84
85 private static long TARGET_STRINGS = Long.getLong("targetStrings", 2_500_000);
86 private static long TARGET_OVERWRITES = Long.getLong("targetOverwrites", 600_000);
87
88 private static final int UNIQUE_STRINGS = 20;
89 static {
90 try {
91 Field field = Unsafe.class.getDeclaredField("theUnsafe");
92 field.setAccessible(true);
93 unsafe = (Unsafe)field.get(null);
94
95 valueField = String.class.getDeclaredField("value");
96 valueField.setAccessible(true);
97 } catch (Exception e) {
98 throw new RuntimeException(e);
99 }
100 }
101
102 private static Object getValue(String string) {
103 try {
104 return valueField.get(string);
105 } catch (Exception e) {
106 throw new RuntimeException(e);
107 }
108 }
109
110 static class StringAndId {
111 private String str;
112 private int id;
113 public StringAndId(String str, int id) {
114 this.str = str;
115 this.id = id;
116 }
117
118 public String str() { return str; }
119 public int id() { return id; }
120 }
121
122 private static void generateStrings(ArrayList<StringAndId> strs, int unique_strs) {
123 Random rn = new Random();
124 for (int u = 0; u < unique_strs; u ++) {
125 int n = Math.abs(rn.nextInt() % 2);
126 for (int index = 0; index < n; index ++) {
127 strs.add(new StringAndId("Unique String " + u, u));
128 }
129 }
130 }
131
132 private static int verifyDedepString(ArrayList<StringAndId> strs) {
133 HashMap<Object, StringAndId> seen = new HashMap<>();
134 int total = 0;
135 int dedup = 0;
136
137 for (StringAndId item : strs) {
138 total ++;
139 StringAndId existing_item = seen.get(getValue(item.str()));
140 if (existing_item == null) {
141 seen.put(getValue(item.str()), item);
142 } else {
143 if (item.id() != existing_item.id() ||
144 !item.str().equals(existing_item.str())) {
145 System.out.println("StringDedup error:");
146 System.out.println("id: " + item.id() + " != " + existing_item.id());
147 System.out.println("or String: " + item.str() + " != " + existing_item.str());
148 throw new RuntimeException("StringDedup Test failed");
149 } else {
150 dedup ++;
151 }
152 }
153 }
154 System.out.println("Dedup: " + dedup + "/" + total + " unique: " + (total - dedup));
155 return (total - dedup);
156 }
157
158 static volatile ArrayList<StringAndId> astrs = new ArrayList<>();
159 public static void main(String[] args) {
160 Random rn = new Random();
161
162 long gen_iterations = TARGET_STRINGS * 2 / UNIQUE_STRINGS;
163
164 for(long index = 0; index < gen_iterations; index ++) {
165 generateStrings(astrs, UNIQUE_STRINGS);
166 }
167
168 for (long loop = 1; loop < TARGET_OVERWRITES; loop ++) {
169 int arr_size = astrs.size();
170 int index = Math.abs(rn.nextInt()) % arr_size;
171 StringAndId item = astrs.get(index);
172 int n = Math.abs(rn.nextInt() % UNIQUE_STRINGS);
173 item.str = "Unique String " + n;
174 item.id = n;
175 }
176
177 verifyDedepString(astrs);
178 }
179 }