1 /*
2  * Copyright (c) 2002, 2020, 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
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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
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17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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20  * or visit www.oracle.com if you need additional information or have any
21  * questions.
22  */
23 
24 
25 /*
26  * @test
27  * @key stress randomness
28  *
29  * @summary converted from VM Testbase gc/memory/Churn/Churn1.
30  * VM Testbase keywords: [gc, stress, stressopt, nonconcurrent]
31  *
32  * @library /vmTestbase
33  *          /test/lib
34  * @run main/othervm gc.memory.Churn.Churn1.Churn1
35  */
36 
37 package gc.memory.Churn.Churn1;
38 
39 import nsk.share.test.*;
40 import nsk.share.gc.*;
41 
42 /**
43  *  Test that GC works with memory that is churn over.
44  *
45  *  This test starts a number of threads that create objects,
46  *  keep references to them in array and overwrite them. The test
47  *  test checks that GC is able to collect these objects.
48  *
49  *  This test will adjust the size of allocated objects to run
50  *  environment.
51  *
52  *  @see nsk.share.gc.RunParams#getTestMemory()
53  */
54 public class Churn1 extends ThreadedGCTest {
55         private int multiplier = 10;
56         private int sizeOfArray;
57 
58         class ThreadObject implements Runnable {
59                 private AllMemoryObject objectArray[] = new AllMemoryObject[sizeOfArray];
60 
ThreadObject()61                 public ThreadObject() {
62                         for (int i = 0; i < sizeOfArray; i ++)
63                                 objectArray[i] = new AllMemoryObject(multiplier * i);
64                 }
65 
run()66                 public void run() {
67                         int index = LocalRandom.nextInt(sizeOfArray);
68                         objectArray[index] = new AllMemoryObject(multiplier * index);
69                 }
70         }
71 
createRunnable(int i)72         protected Runnable createRunnable(int i) {
73                 return new ThreadObject();
74         }
run()75         public void run() {
76                 sizeOfArray = (int) Math.min(Math.sqrt(runParams.getTestMemory() * 2 / runParams.getNumberOfThreads() / multiplier), Integer.MAX_VALUE);
77                 super.run();
78         }
79 
main(String args[])80         public static void main(String args[]) {
81                 GC.runTest(new Churn1(), args);
82         }
83 }
84