1 /*
   2  * Copyright (c) 2017, 2018, Red Hat, Inc. All rights reserved.
   3  *
   4  * This code is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This code is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * version 2 for more details (a copy is included in the LICENSE file that
  12  * accompanied this code).
  13  *
  14  * You should have received a copy of the GNU General Public License version
  15  * 2 along with this work; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  19  * or visit www.oracle.com if you need additional information or have any
  20  * questions.
  21  *
  22  */
  23 
  24 /**
  25  * @test TestHeapDump
  26  * @summary Tests JVMTI heap dumps
  27  * @key gc
  28  * @requires vm.gc.Shenandoah
  29  * @compile TestHeapDump.java
  30  * @run main/othervm/native/timeout=300 -agentlib:TestHeapDump -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx128m -XX:ShenandoahGCHeuristics=aggressive -XX:+UseCompressedOops TestHeapDump
  31  * @run main/othervm/native/timeout=300 -agentlib:TestHeapDump -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -Xmx128m -XX:ShenandoahGCHeuristics=aggressive -XX:-UseCompressedOops TestHeapDump
  32  */
  33 
  34 public class TestHeapDump {
  35 
  36     private static final int NUM_ITER = 10000;
  37 
  38     private static final int ARRAY_SIZE = 1000;
  39 
  40     private static final int EXPECTED_OBJECTS =
  41             ARRAY_SIZE +   // array reachable from instance field
  42                     1 +            // static field root
  43                     1;             // local field root
  44 
  45     static {
  46         try {
  47             System.loadLibrary("TestHeapDump");
  48         } catch (UnsatisfiedLinkError ule) {
  49             System.err.println("Could not load TestHeapDump library");
  50             System.err.println("java.library.path: "
  51                     + System.getProperty("java.library.path"));
  52             throw ule;
  53         }
  54     }
  55 
  56     native static int heapdump(Class<?> filterClass);
  57 
  58     public static void main(String args[]) {
  59         new TestHeapDump().run();
  60     }
  61 
  62     // This root needs to be discovered
  63     static Object root = new TestObject();
  64 
  65     // This field needs to be discovered
  66     TestObject[] array;
  67 
  68     public void run() {
  69         array = new TestObject[ARRAY_SIZE];
  70         for (int i = 0; i < ARRAY_SIZE; i++) {
  71             array[i] = new TestObject();
  72         }
  73         TestObject localRoot = new TestObject();
  74         for (int i = 0; i < NUM_ITER; i++) {
  75             int numObjs = heapdump(TestObject.class);
  76             if (numObjs != EXPECTED_OBJECTS) {
  77                 throw new RuntimeException("Expected " + EXPECTED_OBJECTS + " objects, but got " + numObjs);
  78             }
  79         }
  80     }
  81 
  82     // We look for the instances of this class during the heap scan
  83     public static class TestObject {}
  84 }