1 /* 2 * Copyright (c) 2013, 2014, 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 26 * @bug 7038914 8016341 27 * @summary Verify that the reference handler does not die after an OOME allocating the InterruptedException object 28 * @run main/othervm -XX:-UseGCOverheadLimit -Xmx24M -XX:-UseTLAB OOMEInReferenceHandler 29 * @author peter.levart@gmail.com 30 * @key intermittent 31 */ 32 33 import java.lang.ref.*; 34 35 public class OOMEInReferenceHandler { 36 static Object[] fillHeap() { 37 Object[] first = null, last = null; 38 int size = 1 << 20; 39 while (size > 0) { 40 try { 41 Object[] array = new Object[size]; 42 if (first == null) { 43 first = array; 44 } else { 45 last[0] = array; 46 } 47 last = array; 48 } catch (OutOfMemoryError oome) { 49 size = size >>> 1; 50 } 51 } 52 return first; 53 } 54 55 public static void main(String[] args) throws Exception { 56 // preinitialize the InterruptedException class so that the reference handler 57 // does not die due to OOME when loading the class if it is the first use 58 InterruptedException ie = new InterruptedException("dummy"); 59 60 ThreadGroup tg = Thread.currentThread().getThreadGroup(); 61 for ( 62 ThreadGroup tgn = tg; 63 tgn != null; 64 tg = tgn, tgn = tg.getParent() 65 ) 66 ; 67 68 Thread[] threads = new Thread[tg.activeCount()]; 69 Thread referenceHandlerThread = null; 70 int n = tg.enumerate(threads); 71 for (int i = 0; i < n; i++) { 72 if ("Reference Handler".equals(threads[i].getName())) { 73 referenceHandlerThread = threads[i]; 74 } 75 } 76 77 if (referenceHandlerThread == null) { 78 throw new IllegalStateException("Couldn't find Reference Handler thread."); 79 } 80 81 ReferenceQueue<Object> refQueue = new ReferenceQueue<>(); 82 Object referent = new Object(); 83 WeakReference<Object> weakRef = new WeakReference<>(referent, refQueue); 84 85 Object waste = fillHeap(); 86 87 referenceHandlerThread.interrupt(); 88 89 // allow referenceHandlerThread some time to throw OOME 90 Thread.sleep(500L); 91 92 // release waste & referent 93 waste = null; 94 referent = null; 95 96 // wait at most 10 seconds for success or failure 97 for (int i = 0; i < 20; i++) { 98 if (refQueue.poll() != null) { 99 // Reference Handler thread still working -> success 100 return; 101 } 102 System.gc(); 103 Thread.sleep(500L); // wait a little to allow GC to do it's work before allocating objects 104 if (!referenceHandlerThread.isAlive()) { 105 // Reference Handler thread died -> failure 106 throw new Exception("Reference Handler thread died."); 107 } 108 } 109 110 // no sure answer after 10 seconds 111 throw new IllegalStateException("Reference Handler thread stuck. weakRef.get(): " + weakRef.get()); 112 } 113 }