1 /*
2 * Copyright (c) 2010, 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 import java.io.BufferedReader;
25 import java.io.InputStream;
26 import java.io.InputStreamReader;
27
28 import static jdk.testlibrary.Asserts.assertGreaterThan;
29 import jdk.test.lib.process.ProcessTools;
30
31 import com.sun.tools.attach.AttachNotSupportedException;
32 import com.sun.tools.attach.VirtualMachine;
33
34 import sun.tools.attach.HotSpotVirtualMachine;
35
36 /*
37 * @test
38 * @bug 6942989
39 * @summary Check for WeakReference leak in Logger and anonymous Logger objects
40 * @library /lib/testlibrary
41 * @library /test/lib
42 * @modules jdk.attach/sun.tools.attach
43 * java.logging
44 * @build jdk.test.lib.process.ProcessTools
45 * @run main/othervm -Djdk.attach.allowAttachSelf TestLoggerWeakRefLeak Logger
46 * @run main/othervm -Djdk.attach.allowAttachSelf TestLoggerWeakRefLeak AnonymousLogger
47 */
48 public class TestLoggerWeakRefLeak {
49
50 private static final String TARGET_CLASS = "java.lang.ref.WeakReference";
51 private static final int INSTANCE_COUNT = 100;
52 private static int loggerCount = 0;
53
54 public static void main(String[] args) throws Exception {
55 if (args[0].equals("AnonymousLogger")) {
56 System.out.println("Test for WeakReference leak in AnonymousLogger object");
57 testIfLeaking(TestLoggerWeakRefLeak::callAnonymousLogger);
58 } else {
59 System.out.println("Test for WeakReference leak in Logger object");
60 testIfLeaking(TestLoggerWeakRefLeak::callLogger);
61 }
62 }
63
64 /**
65 * For these particular WeakReference leaks, the count was always observed
66 * to be increasing so if decreasing or the same count is observed,
67 * then there is no leak.
68 */
69 private static void testIfLeaking(Runnable callLogger) throws Exception {
70 long count = 0;
71 int instanceCount = 0;
72 int previousInstanceCount = 0;
73 int increasingCount = 0;
74 int decreasingCount = 0;
75
76 while (true) {
77 callLogger.run();
78 count += INSTANCE_COUNT;
79
80 if ((count % 1000) == 0) {
81 System.out.println("call count = " + count);
82
83 instanceCount = getInstanceCountFromHeapHisto();
84 if (instanceCount > previousInstanceCount) {
85 increasingCount++;
86 } else {
87 decreasingCount++;
88 System.out.println("increasing count: " + increasingCount);
89 System.out.println("decreasing or the same count: " + decreasingCount);
90 System.out.println("Test passed: decreasing or the same instance count is observed");
91 break;
92 }
93 previousInstanceCount = instanceCount;
94 }
95
96 delayExecution();
97 }
98 }
99
100 /**
101 * This Logger call is leaking two different WeakReferences:
102 * - one in LogManager.LogNode
103 * - one in Logger.kids
104 */
105 private static void callLogger() {
106 for (int i = 0; i < INSTANCE_COUNT; i++) {
107 java.util.logging.Logger.getLogger("logger-" + loggerCount);
108 if (++loggerCount >= 25000) {
109 // Limit the Logger namespace used by the test so the weak refs
110 // in LogManager.loggers that are being properly managed
111 // don't skew the counts by too much.
112 loggerCount = 0;
113 }
114 }
115 }
116
117 /**
118 * This Logger call is leaking a WeakReference in Logger.kids
119 */
120 private static void callAnonymousLogger() {
121 for (int i = 0; i < INSTANCE_COUNT; i++) {
122 java.util.logging.Logger.getAnonymousLogger();
123 }
124 }
125
126 /**
127 * 'vm.heapHisto("-live")' will request a full GC
128 */
129 private static int getInstanceCountFromHeapHisto() throws AttachNotSupportedException, Exception {
130 int instanceCount = 0;
131
132 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine
133 .attach(Long.toString(ProcessTools.getProcessId()));
134 try {
135 try (InputStream heapHistoStream = vm.heapHisto("-live");
136 BufferedReader in = new BufferedReader(new InputStreamReader(heapHistoStream))) {
137 String inputLine;
138 while ((inputLine = in.readLine()) != null) {
139 if (inputLine.contains(TARGET_CLASS)) {
140 instanceCount = Integer.parseInt(inputLine
141 .split("[ ]+")[2]);
142 System.out.println("instance count: " + instanceCount);
143 break;
144 }
145 }
146 }
147 } finally {
148 vm.detach();
149 }
150
151 assertGreaterThan(instanceCount, 0, "No instances of " + TARGET_CLASS + " are found");
152
153 return instanceCount;
154 }
155
156 /**
157 * Delay for 1/10 of a second to avoid CPU saturation
158 */
159 private static void delayExecution() {
160 try {
161 Thread.sleep(100);
162 } catch (InterruptedException ie) {
163 // Ignore any exceptions
164 }
165 }
166
167 }