| /* |
| * Copyright (c) 2006, 2015, 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 |
| * @bug 6338874 |
| * @summary Check that notification dispatch is not linear in number of MBeans. |
| * @author Eamonn McManus |
| * @modules java.management.rmi |
| * |
| * @library /lib/testlibrary |
| * @run build jdk.testlibrary.* ListenerScaleTest |
| * @run main ListenerScaleTest |
| */ |
| |
| /* |
| * The notification dispatch logic in the connector server used to be |
| * linear in the number of listeners there were on any MBean. For |
| * example, if there were 1000 MBeans, each with one listener, then |
| * every time a notification was sent it would be compared against |
| * every one of the 1000 MBeans, even though its source ObjectName was |
| * known and could not possibly match the name of 999 of the MBeans. |
| * This test checks that we no longer have linear behaviour. We do |
| * this by registering just one MBean and measuring the time it takes |
| * to send and receive a certain number of notifications from that |
| * MBean. Then we register many other MBeans, each with a listener, |
| * and we make the same measurement as before. The presence of the |
| * extra MBeans with their listeners should not impact the dispatch |
| * time significantly. If it does, the test fails. |
| * |
| * As usual with timing-sensitive tests, we could potentially get |
| * sporadic failures. We fail if the ratio of the time with many |
| * MBeans to the time with just one MBean is more than 500. With the |
| * fix in place, it is usually less than 1, presumably because some |
| * code was being interpreted during the first measurement but had |
| * been compiled by the second. |
| */ |
| |
| import java.util.concurrent.Semaphore; |
| import javax.management.MBeanServer; |
| import javax.management.MBeanServerConnection; |
| import javax.management.MBeanServerFactory; |
| import javax.management.MalformedObjectNameException; |
| import javax.management.Notification; |
| import javax.management.NotificationBroadcasterSupport; |
| import javax.management.NotificationListener; |
| import javax.management.ObjectName; |
| import javax.management.remote.JMXConnector; |
| import javax.management.remote.JMXConnectorFactory; |
| import javax.management.remote.JMXConnectorServer; |
| import javax.management.remote.JMXConnectorServerFactory; |
| import javax.management.remote.JMXServiceURL; |
| |
| import jdk.testlibrary.Platform; |
| |
| public class ListenerScaleTest { |
| private static final int WARMUP_WITH_ONE_MBEAN = 1000; |
| private static final int NOTIFS_TO_TIME = 100; |
| private static final int EXTRA_MBEANS = 20000; |
| |
| private static final ObjectName testObjectName; |
| static { |
| try { |
| testObjectName = new ObjectName("test:type=Sender,number=-1"); |
| } catch (MalformedObjectNameException e) { |
| throw new RuntimeException(e); |
| } |
| } |
| |
| private static volatile int nnotifs; |
| private static volatile long startTime; |
| private static volatile long elapsed; |
| private static final Semaphore sema = new Semaphore(0); |
| |
| private static final NotificationListener timingListener = |
| new NotificationListener() { |
| public void handleNotification(Notification n, Object h) { |
| if (++nnotifs == NOTIFS_TO_TIME) { |
| elapsed = System.nanoTime() - startTime; |
| sema.release(); |
| } |
| } |
| }; |
| |
| private static final long timeNotif(MBeanServer mbs) { |
| try { |
| startTime = System.nanoTime(); |
| nnotifs = 0; |
| mbs.invoke(testObjectName, "send", null, null); |
| sema.acquire(); |
| return elapsed; |
| } catch (Exception e) { |
| throw new RuntimeException(e); |
| } |
| } |
| |
| public static interface SenderMBean { |
| public void send(); |
| } |
| |
| public static class Sender extends NotificationBroadcasterSupport |
| implements SenderMBean { |
| public void send() { |
| for (int i = 0; i < NOTIFS_TO_TIME; i++) |
| sendNotification(new Notification("type", this, 1L)); |
| } |
| } |
| |
| private static final NotificationListener nullListener = |
| new NotificationListener() { |
| public void handleNotification(Notification n, Object h) {} |
| }; |
| |
| public static void main(String[] args) throws Exception { |
| if (Platform.isDebugBuild()) { |
| System.out.println("Running on a debug build. Performance test not applicable. Skipping."); |
| return; |
| } |
| MBeanServer mbs = MBeanServerFactory.newMBeanServer(); |
| Sender sender = new Sender(); |
| mbs.registerMBean(sender, testObjectName); |
| JMXServiceURL url = new JMXServiceURL("service:jmx:rmi://"); |
| JMXConnectorServer cs = |
| JMXConnectorServerFactory.newJMXConnectorServer(url, null, mbs); |
| cs.start(); |
| JMXServiceURL addr = cs.getAddress(); |
| JMXConnector cc = JMXConnectorFactory.connect(addr); |
| try { |
| test(mbs, cs, cc); |
| } finally { |
| cc.close(); |
| cs.stop(); |
| } |
| } |
| |
| private static void test(MBeanServer mbs, JMXConnectorServer cs, |
| JMXConnector cc) throws Exception { |
| MBeanServerConnection mbsc = cc.getMBeanServerConnection(); |
| mbsc.addNotificationListener(testObjectName, timingListener, null, null); |
| long singleMBeanTime = 0; |
| for (int i = 0; i < WARMUP_WITH_ONE_MBEAN; i++) |
| singleMBeanTime = timeNotif(mbs); |
| if (singleMBeanTime == 0) |
| singleMBeanTime = 1; |
| System.out.println("Time with a single MBean: " + singleMBeanTime + "ns"); |
| System.out.println("Now registering " + EXTRA_MBEANS + " MBeans"); |
| for (int i = 0; i < EXTRA_MBEANS; i++) { |
| ObjectName on = new ObjectName("test:type=Sender,number=" + i); |
| mbs.registerMBean(new Sender(), on); |
| if (i % 1000 == 999) { |
| System.out.print("..." + (i+1)); |
| System.out.flush(); |
| } |
| } |
| System.out.println(); |
| System.out.println("Now registering " + EXTRA_MBEANS + " listeners"); |
| for (int i = 0; i < EXTRA_MBEANS; i++) { |
| ObjectName on = new ObjectName("test:type=Sender,number=" + i); |
| mbsc.addNotificationListener(on, nullListener, null, null); |
| if (i % 1000 == 999) { |
| System.out.print("..." + (i+1)); |
| System.out.flush(); |
| } |
| } |
| System.out.println(); |
| System.out.println("Timing a notification send now"); |
| long manyMBeansTime = timeNotif(mbs); |
| System.out.println("Time with many MBeans: " + manyMBeansTime + "ns"); |
| double ratio = (double) manyMBeansTime / singleMBeanTime; |
| if (ratio > 500.0) |
| throw new Exception("Failed: ratio=" + ratio); |
| System.out.println("Test passed: ratio=" + ratio); |
| } |
| } |