1 /*
   2  * Copyright (c) 2013, 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.testlibrary.jfr;
  27 
  28 import java.util.List;
  29 import java.util.HashMap;
  30 
  31 import jdk.jfr.consumer.RecordedEvent;
  32 import jdk.testlibrary.Asserts;
  33 import jdk.testlibrary.jfr.Events;
  34 
  35 class Foo {
  36 }
  37 
  38 class Constants {
  39     public static final int oneMB = 1048576;
  40 }
  41 
  42 public class ObjectCountEventVerifier {
  43     public static Foo[] foos;
  44 
  45     public static void createTestData() {
  46         foos = new Foo[Constants.oneMB];
  47     }
  48 
  49     public static void verify(List<RecordedEvent> objectCountEvents) throws Exception {
  50         Asserts.assertFalse(objectCountEvents.isEmpty(), "Expected at least one object count event");
  51         // Object count events should be sent only for those classes which instances occupy over 0.5%
  52         // of the heap. Therefore there can't be more than 200 events
  53         Asserts.assertLessThanOrEqual(objectCountEvents.size(), 200, "Expected at most 200 object count events");
  54 
  55         HashMap<String, Long> numInstancesOfClass = new HashMap<String, Long>();
  56         HashMap<String, Long> sizeOfInstances = new HashMap<String, Long>();
  57 
  58         for (RecordedEvent event : objectCountEvents) {
  59             String className = Events.assertField(event, "objectClass.name").notEmpty().getValue();
  60             long count = Events.assertField(event, "count").atLeast(0L).getValue();
  61             long totalSize = Events.assertField(event, "totalSize").atLeast(1L).getValue();
  62             System.out.println(className);
  63             numInstancesOfClass.put(className, count);
  64             sizeOfInstances.put(className, totalSize);
  65         }
  66         System.out.println(numInstancesOfClass);
  67         final String fooArrayName = "[Ljdk/testlibrary/jfr/Foo;";
  68         Asserts.assertTrue(numInstancesOfClass.containsKey(fooArrayName), "Expected an event for the Foo array");
  69         Asserts.assertEquals(sizeOfInstances.get(fooArrayName), expectedFooArraySize(Constants.oneMB), "Wrong size of the Foo array");
  70     }
  71 
  72     private static long expectedFooArraySize(long count) {
  73         boolean runsOn32Bit = System.getProperty("sun.arch.data.model").equals("32");
  74         int bytesPerWord = runsOn32Bit ? 4 : 8;
  75         int objectHeaderSize = bytesPerWord * 3; // length will be aligned on 64 bits
  76         int alignmentInOopArray = runsOn32Bit ? 4 : 0;
  77         int ptrSize = bytesPerWord;
  78         return objectHeaderSize + alignmentInOopArray + count * ptrSize;
  79     }
  80 }