1 /*

     2  * Copyright (c) 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 package jdk.jfr.javaagent;

    25 

    26 import java.lang.instrument.Instrumentation;

    27 import java.nio.file.Path;

    28 import java.nio.file.Paths;

    29 

    30 import jdk.jfr.Configuration;

    31 import jdk.jfr.Event;

    32 import jdk.jfr.Name;

    33 import jdk.jfr.Recording;

    34 import jdk.jfr.consumer.RecordingFile;

    35 import jdk.test.lib.Asserts;

    36 import jdk.test.lib.jfr.EventNames;

    37 

    38 // Java agent that emits in multiple threads

    39 public class EventEmitterAgent {

    40 

    41     private static final int THREADS = 5;

    42     private static final int EVENTS_PER_THREAD = 150_000;

    43     private static final int EXPECTED_COUNT = THREADS * EVENTS_PER_THREAD;

    44     private static final Path DUMP_PATH = Paths.get("dump.jfr").toAbsolutePath();

    45 

    46     // Called when agent is loaded from command line

    47     public static void agentmain(String agentArgs, Instrumentation inst) throws Exception {

    48         agentWork();

    49     }

    50 

    51     // Called when agent is dynamically loaded

    52     public static void premain(String agentArgs, Instrumentation inst) throws Exception {

    53         agentWork();

    54     }

    55 

    56     private static void agentWork() throws Exception {

    57         try (Recording r = new Recording(Configuration.getConfiguration("default"))) {

    58             r.enable(EventNames.JavaExceptionThrow);

    59             r.setDestination(DUMP_PATH);

    60             r.start();

    61             Thread[] threads = new Thread[THREADS];

    62             for (int i = 0; i < THREADS; i++) {

    63                 threads[i] = new Thread(EventEmitterAgent::emitEvents);

    64                 threads[i].start();

    65             }

    66             for (int i = 0; i < THREADS; i++) {

    67                 threads[i].join();

    68             }

    69             r.stop();

    70         }

    71     }

    72 

    73     public static void emitEvents() {

    74         for (int i = 0; i < EVENTS_PER_THREAD; i++) {

    75             TestEvent e = new TestEvent();

    76             e.msg = "Long message that puts pressure on the string pool " + i % 100;

    77             e.count = i;

    78             e.thread = Thread.currentThread();

    79             e.clazz = String.class;

    80             e.commit();

    81             if (i % 10000 == 0) {

    82                 try {

    83                     Thread.sleep(1);

    84                 } catch (InterruptedException ie) {

    85                     // ignore

    86                 }

    87             }

    88         }

    89     }

    90 

    91     @Name("Test")

    92     static class TestEvent extends Event {

    93         String msg;

    94         int count;

    95         Thread thread;

    96         Class<?> clazz;

    97     }

    98 

    99     public static void validateRecording() throws Exception {

   100         long testEventCount = RecordingFile.readAllEvents(DUMP_PATH)

   101                 .stream()

   102                 .filter(e -> e.getEventType().getName().equals("Test"))

   103                 .count();

   104         Asserts.assertTrue(testEventCount == EXPECTED_COUNT, "Mismatch in TestEvent count");

   105     }

   106 }