1 /*
2 * Copyright (c) 2014, 2015, 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 /**
25 * @test TestSoftReferencesBehaviorOnOOME
26 * @key gc
27 * @summary Tests that all SoftReferences has been cleared at time of OOM.
28 * @library /testlibrary
29 * @modules java.base/jdk.internal.misc
30 * java.management
31 * @build TestSoftReferencesBehaviorOnOOME
32 * @run main/othervm -Xmx128m TestSoftReferencesBehaviorOnOOME 512 2k
33 * @run main/othervm -Xmx128m TestSoftReferencesBehaviorOnOOME 128k 256k
34 * @run main/othervm -Xmx128m TestSoftReferencesBehaviorOnOOME 2k 32k
35 */
36 import jdk.test.lib.Utils;
37 import jdk.test.lib.Asserts;
38 import java.lang.ref.SoftReference;
39 import java.util.LinkedList;
40 import java.util.Random;
41
42 public class TestSoftReferencesBehaviorOnOOME {
43
44 /**
45 * Test generates a lot of soft references to objects with random payloads.
46 * Then it provokes OOME and checks that all SoftReferences has been gone
47 * @param args - [minSize] [maxSize] [freq]
48 * where
49 * - minSize - min size of random objects
50 * - maxSize - max size of random objects
51 */
52 public static void main(String[] args) {
53 long minSize = DEFAULT_MIN_SIZE;
54 long maxSize = DEFAULT_MAX_SIZE;
55
56 if ( args.length >= 2) {
57 maxSize = getBytesCount(args[1]);
58 }
59
60 if ( args.length >= 1) {
61 minSize = getBytesCount(args[0]);
62 }
63
64 new TestSoftReferencesBehaviorOnOOME().softReferencesOom(minSize, maxSize);
65 }
66
67 /**
68 * Test that all SoftReferences has been cleared at time of OOM.
69 */
70 void softReferencesOom(long minSize, long maxSize) {
71 System.out.format( "minSize = %d, maxSize = %d%n", minSize, maxSize );
72
73 LinkedList<SoftReference> arrSoftRefs = new LinkedList();
74 staticRef = arrSoftRefs;
75 LinkedList arrObjects = new LinkedList();
76 staticRef = arrObjects;
77
78 long multiplier = maxSize - minSize;
79 long numberOfNotNulledObjects = 0;
80
81 try {
82
83 // Lets allocate as many as we can - taking size of all SoftRerefences
84 // by minimum. So it can provoke some GC but we surely will allocate enough.
85 long numSofts = (long) ((0.95 * Runtime.getRuntime().totalMemory()) / minSize);
86 System.out.println("num Soft: " + numSofts);
87
88 while (numSofts-- > 0) {
89 int allocationSize = ((int) (RND_GENERATOR.nextDouble() * multiplier))
90 + (int)minSize;
91 arrSoftRefs.add(new SoftReference(new byte[allocationSize]));
92 }
93
94 System.out.println("free: " + Runtime.getRuntime().freeMemory());
95
96 // provoke OOME.
97 while (true) {
98 arrObjects.add(new byte[(int) Runtime.getRuntime().totalMemory()]);
99 }
100
101 } catch (OutOfMemoryError oome) {
102
103 // Clear allocated ballast, so we don't get another OOM.
104 staticRef = null;
105 arrObjects = null;
106 long oomSoftArraySize = arrSoftRefs.size();
107
108 for (SoftReference sr : arrSoftRefs) {
109 Object o = sr.get();
110
111 if (o != null) {
112 numberOfNotNulledObjects++;
113 }
114 }
115
116 // Make sure we clear all refs before we return failure
117 arrSoftRefs = null;
118 Asserts.assertFalse(numberOfNotNulledObjects > 0,
119 "" + numberOfNotNulledObjects + " out of "
120 + oomSoftArraySize + " SoftReferences was not "
121 + "null at time of OutOfMemoryError"
122 );
123 } finally {
124 Asserts.assertTrue(arrObjects == null, "OOME hasn't been provoked");
125 Asserts.assertTrue(arrSoftRefs == null, "OOME hasn't been provoked");
126 }
127 }
128
129 private static final long getBytesCount(String arg) {
130 String postfixes = "kMGT";
131 long mod = 1;
132
133 if (arg.trim().length() >= 2) {
134 mod = postfixes.indexOf(arg.trim().charAt(arg.length() - 1));
135
136 if (mod != -1) {
137 mod = (long) Math.pow(1024, mod+1);
138 arg = arg.substring(0, arg.length() - 1);
139 } else {
140 mod = 1; // 10^0
141 }
142 }
143
144 return Long.parseLong(arg) * mod;
145 }
146
147 private static final Random RND_GENERATOR = Utils.getRandomInstance();
148 private static final long DEFAULT_MIN_SIZE = 512;
149 private static final long DEFAULT_MAX_SIZE = 1024;
150 private static Object staticRef; // to prevent compile optimisations
151 }