1 /*
2 * Copyright (c) 2014, 2016, 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 /test/lib
29 * @modules java.base/jdk.internal.misc
30 * java.management
31 * @run main/othervm -Xmx128m TestSoftReferencesBehaviorOnOOME 512 2k
32 * @run main/othervm -Xmx128m TestSoftReferencesBehaviorOnOOME 128k 256k
33 * @run main/othervm -Xmx128m TestSoftReferencesBehaviorOnOOME 2k 32k
34 */
35 import jdk.test.lib.Utils;
36 import jdk.test.lib.Asserts;
37 import java.lang.ref.SoftReference;
38 import java.util.LinkedList;
39 import java.util.Random;
40
41 public class TestSoftReferencesBehaviorOnOOME {
42
43 /**
44 * Test generates a lot of soft references to objects with random payloads.
45 * Then it provokes OOME and checks that all SoftReferences has been gone
46 * @param args - [minSize] [maxSize] [freq]
47 * where
48 * - minSize - min size of random objects
49 * - maxSize - max size of random objects
50 */
51 public static void main(String[] args) {
52 long minSize = DEFAULT_MIN_SIZE;
53 long maxSize = DEFAULT_MAX_SIZE;
54
55 if ( args.length >= 2) {
56 maxSize = getBytesCount(args[1]);
57 }
58
59 if ( args.length >= 1) {
60 minSize = getBytesCount(args[0]);
61 }
62
63 new TestSoftReferencesBehaviorOnOOME().softReferencesOom(minSize, maxSize);
64 }
65
66 /**
67 * Test that all SoftReferences has been cleared at time of OOM.
68 */
69 void softReferencesOom(long minSize, long maxSize) {
70 System.out.format( "minSize = %d, maxSize = %d%n", minSize, maxSize );
71
72 LinkedList<SoftReference> arrSoftRefs = new LinkedList();
73 staticRef = arrSoftRefs;
74 LinkedList arrObjects = new LinkedList();
75 staticRef = arrObjects;
76
77 long multiplier = maxSize - minSize;
78 long numberOfNotNulledObjects = 0;
79
80 try {
81
82 // Lets allocate as many as we can - taking size of all SoftRerefences
83 // by minimum. So it can provoke some GC but we surely will allocate enough.
84 long numSofts = (long) ((0.95 * Runtime.getRuntime().totalMemory()) / minSize);
85 System.out.println("num Soft: " + numSofts);
86
87 while (numSofts-- > 0) {
88 int allocationSize = ((int) (RND_GENERATOR.nextDouble() * multiplier))
89 + (int)minSize;
90 arrSoftRefs.add(new SoftReference(new byte[allocationSize]));
91 }
92
93 System.out.println("free: " + Runtime.getRuntime().freeMemory());
94
95 // provoke OOME.
96 while (true) {
97 arrObjects.add(new byte[(int) Runtime.getRuntime().totalMemory()]);
98 }
99
100 } catch (OutOfMemoryError oome) {
101
102 // Clear allocated ballast, so we don't get another OOM.
103 staticRef = null;
104 arrObjects = null;
105 long oomSoftArraySize = arrSoftRefs.size();
106
107 for (SoftReference sr : arrSoftRefs) {
108 Object o = sr.get();
109
110 if (o != null) {
111 numberOfNotNulledObjects++;
112 }
113 }
114
115 // Make sure we clear all refs before we return failure
116 arrSoftRefs = null;
117 Asserts.assertFalse(numberOfNotNulledObjects > 0,
118 "" + numberOfNotNulledObjects + " out of "
119 + oomSoftArraySize + " SoftReferences was not "
120 + "null at time of OutOfMemoryError"
121 );
122 } finally {
123 Asserts.assertTrue(arrObjects == null, "OOME hasn't been provoked");
124 Asserts.assertTrue(arrSoftRefs == null, "OOME hasn't been provoked");
125 }
126 }
127
128 private static final long getBytesCount(String arg) {
129 String postfixes = "kMGT";
130 long mod = 1;
131
132 if (arg.trim().length() >= 2) {
133 mod = postfixes.indexOf(arg.trim().charAt(arg.length() - 1));
134
135 if (mod != -1) {
136 mod = (long) Math.pow(1024, mod+1);
137 arg = arg.substring(0, arg.length() - 1);
138 } else {
139 mod = 1; // 10^0
140 }
141 }
142
143 return Long.parseLong(arg) * mod;
144 }
145
146 private static final Random RND_GENERATOR = Utils.getRandomInstance();
147 private static final long DEFAULT_MIN_SIZE = 512;
148 private static final long DEFAULT_MAX_SIZE = 1024;
149 private static Object staticRef; // to prevent compile optimisations
150 }