1 /*
 2  * Copyright (c) 2018, 2025, 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.event.oldobject;
25 
26 import java.util.ArrayList;
27 import java.util.List;
28 
29 import jdk.jfr.Recording;
30 import jdk.jfr.internal.test.WhiteBox;
31 import jdk.test.lib.jfr.EventNames;
32 
33 /**
34  * @test
35  * @requires vm.flagless
36  * @requires vm.hasJFR
37  * @library /test/lib /test/jdk
38  * @modules jdk.jfr/jdk.jfr.internal.test
39  * @run main/othervm -XX:TLABSize=2k jdk.jfr.event.oldobject.TestHeapShallow
40  */
41 public class TestHeapShallow {
42     private final static long LARGE_OBJECT_FACTOR = 509; // prime number
43 
44     static class LeakObject {
45         Object object = null;
46 
47         public LeakObject(Object object) {
48             this.object = object;
49         }
50     }
51 
52     public static ArrayList<LeakObject> leak =  new ArrayList<>(OldObjects.MIN_SIZE);
53 
54     public static void main(String[] args) throws Exception {
55         WhiteBox.setWriteAllObjectSamples(true);
56 
57         try (Recording recording = new Recording()) {
58             recording.enable(EventNames.OldObjectSample).withStackTrace().with("cutoff", "infinity");
59             recording.start();
60 
61             addObjectsToShallowArray(leak);
62             recording.stop();
63             if (OldObjects.countMatchingEvents(recording, "addObjectsToShallowArray", byte[].class, "object", LeakObject.class, -1) < 1) {
64                 throw new Exception("Could not find shallow leak object");
65             }
66         }
67     }
68 
69     private static void addObjectsToShallowArray(List<LeakObject> list) {
70         for (int i = 0; i < OldObjects.MIN_SIZE; i++) {
71             if (i % LARGE_OBJECT_FACTOR == 0) {
72                 // Triggers allocation outside TLAB path
73                 list.add(new LeakObject(new byte[16384]));
74             } else {
75                 // Triggers allocation in TLAB path
76                 list.add(new LeakObject(new byte[10]));
77             }
78         }
79     }
80 }