1 /*
2 * Copyright Amazon.com Inc. 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
25 package gc.shenandoah.generational;
26
27 import jdk.test.whitebox.WhiteBox;
28 import java.util.Random;
29 import java.util.HashMap;
30
31 /*
32 * To avoid the risk of false regressions identified by this test, the heap
33 * size is set artificially high. Though this test is known to run reliably
34 * in 66 MB heap, the heap size for this test run is currently set to 256 MB.
35 */
36
37 /*
38 * @test id=generational
39 * @requires vm.gc.Shenandoah
40 * @summary Confirm that card marking and remembered set scanning do not crash.
41 * @library /testlibrary /test/lib /
42 * @build jdk.test.whitebox.WhiteBox
43 * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
44 * @run main/othervm -Xbootclasspath/a:.
45 * -Xms256m -Xmx256m
46 * -XX:+IgnoreUnrecognizedVMOptions
47 * -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
48 * -XX:+UseShenandoahGC -XX:ShenandoahGCMode=generational
49 * -XX:NewRatio=1 -XX:+UnlockExperimentalVMOptions
50 * -XX:ShenandoahGuaranteedGCInterval=3000
51 * -XX:-UseDynamicNumberOfGCThreads -XX:-ShenandoahPacing
52 * gc.shenandoah.generational.TestConcurrentEvac
53 */
54
55 public class TestConcurrentEvac {
56 private static WhiteBox wb = WhiteBox.getWhiteBox();
57
58 private static final int RANDOM_SEED = 46;
59
60 // Smaller table will cause creation of more old-gen garbage
61 // as previous entries in table are overwritten with new values.
62 private static final int TABLE_SIZE = 53;
63 private static final int MAX_STRING_LENGTH = 47;
64 private static final int SENTENCE_LENGTH = 5;
65
66 private static Random random = new Random(RANDOM_SEED);
67
68 public static class Node {
69
70 private String name;
71
72 // Each Node instance holds an array containing all substrings of its name
73
74 // This array has entries from 0 .. (name.length() - 1).
75 // numSubstrings[i] represents the number of substrings that
76 // correspond to a name of length i+1.
77 private static int [] numSubstrings;
78
79 static {
80 // Initialize numSubstrings.
81 // For a name of length N, there are
82 // N substrings of length 1
83 // N-1 substrings of length 2
84 // N-2 substrings of length 3
85 // ...
86 // 1 substring of length N
87 // Note that:
88 // numSubstrings[0] = 1
89 // numSubstrings[1] = 3
90 // numSubstrings[i] = (i + 1) + numSubstrings[i - 1]
91 numSubstrings = new int[MAX_STRING_LENGTH];
92 numSubstrings[0] = 1;
93 for (int i = 1; i < MAX_STRING_LENGTH; i++) {
94 numSubstrings[i] = (i + 1) + numSubstrings[i - 1];
95 }
96 }
97
98 private String [] substrings;
99 private Node [] neighbors;
100
101 public Node(String name) {
102 this.name = name;
103 this.substrings = new String[numSubstrings[name.length() - 1]];
104
105 int index = 0;
106 for (int substringLength = 1; substringLength <= name.length(); substringLength++) {
107 for (int offset = 0; offset + substringLength <= name.length(); offset++) {
108 this.substrings[index++] = name.substring(offset, offset + substringLength);
109 }
110 }
111 }
112
113 public String value() {
114 return name;
115 }
116
117 public String arbitrarySubstring() {
118 int index = TestConcurrentEvac.randomUnsignedInt(substrings.length);
119 return substrings[index];
120 }
121 }
122
123
124 // Return random int between 1 and MAX_STRING_LENGTH inclusive
125 static int randomStringLength() {
126 return randomUnsignedInt(MAX_STRING_LENGTH - 1) + 1;
127 }
128
129 static String randomCharacter() {
130 int index = randomUnsignedInt(52);
131 return "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ".substring(index, index + 1);
132 }
133
134 static String randomString() {
135 int length = randomStringLength();
136 String result = new String(); // make the compiler work for this garbage...
137 for (int i = 0; i < length; i++) {
138 result += randomCharacter();
139 }
140 return result;
141 }
142
143 static int randomUnsignedInt(int max) {
144 return random.nextInt(max);
145 }
146
147 static int randomIndex() {
148 return randomUnsignedInt(TABLE_SIZE);
149 }
150
151 public static void main(String args[]) throws Exception {
152 HashMap<Integer, Node> table = new HashMap<Integer, Node>(TABLE_SIZE);
153
154 if (!wb.getBooleanVMFlag("UseShenandoahGC") || !wb.getStringVMFlag("ShenandoahGCMode").equals("generational")) {
155 throw new IllegalStateException("Command-line options not honored!");
156 }
157
158 for (int count = java.lang.Integer.MAX_VALUE/1024; count >= 0; count--) {
159 int index = randomIndex();
160 String name = randomString();
161 table.put(index, new Node(name));
162 }
163
164 String conclusion = "";
165
166 for (int i = 0; i < SENTENCE_LENGTH; i++) {
167 Node node = table.get(randomIndex());
168 if (node == null) {
169 i--;
170 } else {
171 String s = node.arbitrarySubstring();
172 conclusion += s;
173 conclusion += " ";
174 }
175 }
176
177 conclusion = conclusion.substring(0, conclusion.length() - 1);
178
179 System.out.println("Conclusion is [" + conclusion + "]");
180
181 if (!conclusion.equals("HN TInkzoLSDFVJYM mQAirHXbbgCJmUWozx DeispxWF MYFKBh")) {
182 throw new IllegalStateException("Random sequence of words did not end well!");
183 }
184 }
185 }