1 /*
   2  * Copyright (c) 2013, 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 /**
  25  * @test
  26  * @library /runtime/testlibrary
  27  * @build GeneratedClassLoader
  28  * @run main/othervm/timeout=200 FragmentMetaspace
  29  */
  30 
  31 import java.io.IOException;
  32 
  33 /**
  34  * Test that tries to fragment the native memory used by class loaders.
  35  * This test creates class loaders that load classes of increasing size for every
  36  * iteration. By increasing the size of the class meta data needed for every iteration
  37  * we stress the subsystem for allocating native memory for meta data.
  38  */
  39 public class FragmentMetaspace {
  40 
  41     public static void main(String... args) {
  42         runGrowing(Long.valueOf(System.getProperty("time", "80000")));
  43         // try to clean up and unload classes to decrease
  44         // class verification time in debug vm
  45         System.gc();
  46     }
  47 
  48     private static void runGrowing(long time) {
  49         long startTime = System.currentTimeMillis();
  50         for (int i = 0; System.currentTimeMillis() < startTime + time; ++i) {
  51             try {
  52                 GeneratedClassLoader gcl = new GeneratedClassLoader();
  53 
  54                 Class<?> c = gcl.getGeneratedClasses(i, 100)[0];
  55                 c.newInstance();
  56                 c = null;
  57 
  58                 gcl = null;
  59             } catch (IOException|InstantiationException|IllegalAccessException ex) {
  60                 throw new RuntimeException(ex);
  61             }
  62         }
  63     }
  64 }