| /* |
| * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * Test low memory detection of non-heap memory pool. |
| * |
| * The test set a listener to be notified when any of the non-heap pools |
| * exceed 80%. It then starts a thread that continuously loads classes. |
| * In the HotSpot implementation this causes perm space to be consumed. |
| * Test completes when we the notification is received or an OutOfMemory |
| * is generated. |
| */ |
| |
| import java.lang.management.*; |
| import javax.management.*; |
| import javax.management.openmbean.CompositeData; |
| import java.util.*; |
| |
| public class LowMemoryTest2 { |
| |
| private static volatile boolean listenerInvoked = false; |
| |
| private static String INDENT = " "; |
| |
| static class SensorListener implements NotificationListener { |
| public void handleNotification(Notification notif, Object handback) { |
| String type = notif.getType(); |
| if (type.equals(MemoryNotificationInfo.MEMORY_THRESHOLD_EXCEEDED) || |
| type.equals(MemoryNotificationInfo. |
| MEMORY_COLLECTION_THRESHOLD_EXCEEDED)) { |
| listenerInvoked = true; |
| MemoryNotificationInfo minfo = MemoryNotificationInfo. |
| from((CompositeData) notif.getUserData()); |
| |
| System.out.print("Notification for " + minfo.getPoolName()); |
| System.out.print(" [type = " + type); |
| System.out.println(" count = " + minfo.getCount() + "]"); |
| System.out.println(INDENT + "usage = " + minfo.getUsage()); |
| } |
| } |
| } |
| |
| // Loads classes Test100001, Test100002, .... until OutOfMemoryErrror or |
| // low memory notification |
| |
| static class BoundlessLoaderThread extends ClassLoader implements Runnable { |
| |
| static int count = 100000; |
| |
| Class loadNext() throws ClassNotFoundException { |
| |
| // public class TestNNNNNN extends java.lang.Object{ |
| // public TestNNNNNN(); |
| // Code: |
| // 0: aload_0 |
| // 1: invokespecial #1; //Method java/lang/Object."<init>":()V |
| // 4: return |
| // } |
| |
| int begin[] = { |
| 0xca, 0xfe, 0xba, 0xbe, 0x00, 0x00, 0x00, 0x30, |
| 0x00, 0x0a, 0x0a, 0x00, 0x03, 0x00, 0x07, 0x07, |
| 0x00, 0x08, 0x07, 0x00, 0x09, 0x01, 0x00, 0x06, |
| 0x3c, 0x69, 0x6e, 0x69, 0x74, 0x3e, 0x01, 0x00, |
| 0x03, 0x28, 0x29, 0x56, 0x01, 0x00, 0x04, 0x43, |
| 0x6f, 0x64, 0x65, 0x0c, 0x00, 0x04, 0x00, 0x05, |
| 0x01, 0x00, 0x0a, 0x54, 0x65, 0x73, 0x74 }; |
| |
| int end [] = { |
| 0x01, 0x00, 0x10, |
| 0x6a, 0x61, 0x76, 0x61, 0x2f, 0x6c, 0x61, 0x6e, |
| 0x67, 0x2f, 0x4f, 0x62, 0x6a, 0x65, 0x63, 0x74, |
| 0x00, 0x21, 0x00, 0x02, 0x00, 0x03, 0x00, 0x00, |
| 0x00, 0x00, 0x00, 0x01, 0x00, 0x01, 0x00, 0x04, |
| 0x00, 0x05, 0x00, 0x01, 0x00, 0x06, 0x00, 0x00, |
| 0x00, 0x11, 0x00, 0x01, 0x00, 0x01, 0x00, 0x00, |
| 0x00, 0x05, 0x2a, 0xb7, 0x00, 0x01, 0xb1, 0x00, |
| 0x00, 0x00, 0x00, 0x00, 0x00 }; |
| |
| |
| // TestNNNNNN |
| |
| String name = "Test" + Integer.toString(count++); |
| |
| byte value[]; |
| try { |
| value = name.substring(4).getBytes("UTF-8"); |
| } catch (java.io.UnsupportedEncodingException x) { |
| throw new Error(); |
| } |
| |
| // construct class file |
| |
| int len = begin.length + value.length + end.length; |
| byte b[] = new byte[len]; |
| int i, pos=0; |
| for (i=0; i<begin.length; i++) { |
| b[pos++] = (byte)begin[i]; |
| } |
| for (i=0; i<value.length; i++) { |
| b[pos++] = value[i]; |
| } |
| for (i=0; i<end.length; i++) { |
| b[pos++] = (byte)end[i]; |
| } |
| |
| return defineClass(name, b, 0, b.length); |
| } |
| |
| /* |
| * Run method for thread that continuously loads classes. |
| * |
| * Note: Once the usage threshold has been exceeded the low memory |
| * detector thread will attempt to deliver its notification - this can |
| * potentially create a race condition with this thread contining to |
| * fill up perm space. To avoid the low memory detector getting an OutOfMemory |
| * we throttle this thread once the threshold has been exceeded. |
| */ |
| public void run() { |
| List pools = ManagementFactory.getMemoryPoolMXBeans(); |
| boolean thresholdExceeded = false; |
| |
| for (;;) { |
| try { |
| // the classes are small so we load 10 at a time |
| for (int i=0; i<10; i++) { |
| loadNext(); |
| } |
| } catch (ClassNotFoundException x) { |
| return; |
| } |
| if (listenerInvoked) { |
| return; |
| } |
| |
| // if threshold has been exceeded we put in a delay to allow |
| // the low memory detector do its job. |
| if (thresholdExceeded) { |
| try { |
| Thread.currentThread().sleep(100); |
| } catch (InterruptedException x) { } |
| } else { |
| // check if the threshold has been exceeded |
| ListIterator i = pools.listIterator(); |
| while (i.hasNext()) { |
| MemoryPoolMXBean p = (MemoryPoolMXBean) i.next(); |
| if (p.getType() == MemoryType.NON_HEAP && |
| p.isUsageThresholdSupported()) |
| { |
| thresholdExceeded = p.isUsageThresholdExceeded(); |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| public static void main(String args[]) { |
| ListIterator iter = ManagementFactory.getMemoryPoolMXBeans().listIterator(); |
| |
| // Set threshold of 80% of all NON_HEAP memory pools |
| // In the Hotspot implementation this means we should get a notification |
| // if the CodeCache or perm generation fills up. |
| |
| while (iter.hasNext()) { |
| MemoryPoolMXBean p = (MemoryPoolMXBean) iter.next(); |
| if (p.getType() == MemoryType.NON_HEAP && p.isUsageThresholdSupported()) { |
| |
| // set threshold |
| MemoryUsage mu = p.getUsage(); |
| long threshold = (mu.getMax() * 80) / 100; |
| |
| p.setUsageThreshold(threshold); |
| |
| System.out.println("Selected memory pool for low memory " + |
| "detection."); |
| MemoryUtil.printMemoryPool(p); |
| |
| } |
| } |
| |
| |
| // Install the listener |
| |
| MemoryMXBean mm = ManagementFactory.getMemoryMXBean(); |
| SensorListener l2 = new SensorListener(); |
| |
| NotificationEmitter emitter = (NotificationEmitter) mm; |
| emitter.addNotificationListener(l2, null, null); |
| |
| // Start the thread loading classes |
| |
| Thread thr = new Thread(new BoundlessLoaderThread()); |
| thr.start(); |
| |
| // Wait for the thread to terminate |
| try { |
| thr.join(); |
| } catch (InterruptedException x) { |
| throw new RuntimeException(x); |
| } |
| |
| if (listenerInvoked) { |
| System.out.println("Notification received - test passed."); |
| } else { |
| throw new RuntimeException("Test failed - notification not received!"); |
| } |
| } |
| |
| } |
