1 /* 2 * Copyright (c) 2010, 2019, 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.test.lib.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 /test/lib 41 * @modules jdk.attach/sun.tools.attach 42 * java.logging 43 * @build jdk.test.lib.process.ProcessTools 44 * @run main/othervm -Djdk.attach.allowAttachSelf TestLoggerWeakRefLeak Logger 45 * @run main/othervm -Djdk.attach.allowAttachSelf TestLoggerWeakRefLeak AnonymousLogger 46 */ 47 public class TestLoggerWeakRefLeak { 48 49 private static final String TARGET_CLASS = "java.lang.ref.WeakReference"; 50 private static final int INSTANCE_COUNT = 100; 51 private static int loggerCount = 0; 52 main(String[] args)53 public static void main(String[] args) throws Exception { 54 if (args[0].equals("AnonymousLogger")) { 55 System.out.println("Test for WeakReference leak in AnonymousLogger object"); 56 testIfLeaking(TestLoggerWeakRefLeak::callAnonymousLogger); 57 } else { 58 System.out.println("Test for WeakReference leak in Logger object"); 59 testIfLeaking(TestLoggerWeakRefLeak::callLogger); 60 } 61 } 62 63 /** 64 * For these particular WeakReference leaks, the count was always observed 65 * to be increasing so if decreasing or the same count is observed, 66 * then there is no leak. 67 */ testIfLeaking(Runnable callLogger)68 private static void testIfLeaking(Runnable callLogger) throws Exception { 69 long count = 0; 70 int instanceCount = 0; 71 int previousInstanceCount = 0; 72 int increasingCount = 0; 73 int decreasingCount = 0; 74 75 while (true) { 76 callLogger.run(); 77 count += INSTANCE_COUNT; 78 79 if ((count % 1000) == 0) { 80 System.out.println("call count = " + count); 81 82 instanceCount = getInstanceCountFromHeapHisto(); 83 if (instanceCount > previousInstanceCount) { 84 increasingCount++; 85 } else { 86 decreasingCount++; 87 System.out.println("increasing count: " + increasingCount); 88 System.out.println("decreasing or the same count: " + decreasingCount); 89 System.out.println("Test passed: decreasing or the same instance count is observed"); 90 break; 91 } 92 previousInstanceCount = instanceCount; 93 } 94 95 delayExecution(); 96 } 97 } 98 99 /** 100 * This Logger call is leaking two different WeakReferences: 101 * - one in LogManager.LogNode 102 * - one in Logger.kids 103 */ callLogger()104 private static void callLogger() { 105 for (int i = 0; i < INSTANCE_COUNT; i++) { 106 java.util.logging.Logger.getLogger("logger-" + loggerCount); 107 if (++loggerCount >= 25000) { 108 // Limit the Logger namespace used by the test so the weak refs 109 // in LogManager.loggers that are being properly managed 110 // don't skew the counts by too much. 111 loggerCount = 0; 112 } 113 } 114 } 115 116 /** 117 * This Logger call is leaking a WeakReference in Logger.kids 118 */ callAnonymousLogger()119 private static void callAnonymousLogger() { 120 for (int i = 0; i < INSTANCE_COUNT; i++) { 121 java.util.logging.Logger.getAnonymousLogger(); 122 } 123 } 124 125 /** 126 * 'vm.heapHisto("-live")' will request a full GC 127 */ getInstanceCountFromHeapHisto()128 private static int getInstanceCountFromHeapHisto() throws AttachNotSupportedException, Exception { 129 int instanceCount = 0; 130 131 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) VirtualMachine 132 .attach(Long.toString(ProcessTools.getProcessId())); 133 try { 134 try (InputStream heapHistoStream = vm.heapHisto("-live"); 135 BufferedReader in = new BufferedReader(new InputStreamReader(heapHistoStream))) { 136 String inputLine; 137 while ((inputLine = in.readLine()) != null) { 138 if (inputLine.contains(TARGET_CLASS)) { 139 instanceCount = Integer.parseInt(inputLine 140 .split("[ ]+")[2]); 141 System.out.println("instance count: " + instanceCount); 142 break; 143 } 144 } 145 } 146 } finally { 147 vm.detach(); 148 } 149 150 assertGreaterThan(instanceCount, 0, "No instances of " + TARGET_CLASS + " are found"); 151 152 return instanceCount; 153 } 154 155 /** 156 * Delay for 1/10 of a second to avoid CPU saturation 157 */ delayExecution()158 private static void delayExecution() { 159 try { 160 Thread.sleep(100); 161 } catch (InterruptedException ie) { 162 // Ignore any exceptions 163 } 164 } 165 166 } 167