1 /*
   2  * Copyright (c) 2013, 2016, 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  * @modules java.base/jdk.internal.misc
  28  * @modules java.compiler
  29  * @run main/othervm/timeout=200 -Xmx1g FragmentMetaspace
  30  */
  31 
  32 import java.io.IOException;
  33 
  34 /**
  35  * Test that tries to fragment the native memory used by class loaders.
  36  * This test creates class loaders that load classes of increasing size for every
  37  * iteration. By increasing the size of the class meta data needed for every iteration
  38  * we stress the subsystem for allocating native memory for meta data.
  39  */
  40 public class FragmentMetaspace {
  41 
  42     public static Class<?> c;
  43 
  44     public static void main(String... args) {
  45         runGrowing(Long.valueOf(System.getProperty("time", "40000")),
  46             Integer.valueOf(System.getProperty("iterations", "100")));
  47         // try to clean up and unload classes to decrease
  48         // class verification time in debug vm
  49         System.gc();
  50     }
  51 
  52     private static void runGrowing(long time, int iterations) {
  53         long startTime = System.currentTimeMillis();
  54         for (int i = 0; System.currentTimeMillis() < startTime + time && i < iterations; ++i) {
  55             try {
  56                 GeneratedClassLoader gcl = new GeneratedClassLoader();
  57 
  58                 // getGeneratedClasses throws a RuntimeException in cases where
  59                 // the javac exit code is not 0. If the original reason for the exception is
  60                 // a "java.lang.OutOfMemoryError: Java heap space",
  61                 // increase the heap size in the @run tag and rerun the test.
  62                 // The heap can be exhausted by this test, but heap exhaustion
  63                 // is not a failure mode of this test and should be ignored.
  64                 c = gcl.getGeneratedClasses(i, 100)[0];
  65                 c.newInstance();
  66                 c = null;
  67 
  68                 gcl = null;
  69             } catch (IOException | InstantiationException | IllegalAccessException ex) {
  70                 throw new RuntimeException(ex);
  71             } catch (OutOfMemoryError oome) {
  72                 System.out.println("javac failed with OOM; ignored.");
  73                 return;
  74             }
  75         }
  76     }
  77 }