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 /test/lib classes 27 * @build test.Empty 28 * @run driver ClassFileInstaller test.Empty 29 * @run main/othervm/timeout=200 FragmentMetaspaceSimple 30 */ 31 32 import java.io.DataInputStream; 33 import java.io.File; 34 import java.io.FileInputStream; 35 import java.io.IOException; 36 import java.util.ArrayList; 37 38 /** 39 * Test that tries to fragment the native memory used by class loaders. 40 * Keeps every other class loader alive in order to fragment the memory space 41 * used to store classes and meta data. Since the memory is probably allocated in 42 * chunks per class loader this will cause a lot of fragmentation if not handled 43 * properly since every other chunk will be unused. 44 */ 45 public class FragmentMetaspaceSimple { 46 public static void main(String... args) { 47 runSimple(Long.valueOf(System.getProperty("time", "80000"))); 48 System.gc(); 49 } 50 51 private static void runSimple(long time) { 52 long startTime = System.currentTimeMillis(); 53 ArrayList<ClassLoader> cls = new ArrayList<>(); 54 char sep = File.separatorChar; 55 String fileName = "test" + sep + "Empty.class"; 56 File file = new File(fileName); 57 byte buff[] = read(file); 58 59 int i = 0; 60 for (i = 0; System.currentTimeMillis() < startTime + time; ++i) { 61 ClassLoader ldr = new MyClassLoader(buff); 62 if (i % 1000 == 0) { 63 cls.clear(); 64 } 65 // only keep every other class loader alive 66 if (i % 2 == 1) { 67 cls.add(ldr); 68 } 69 Class<?> c = null; 70 try { 71 c = ldr.loadClass("test.Empty"); 72 c.getClass().getClassLoader(); // make sure we have a valid class. 73 } catch (ClassNotFoundException ex) { 74 System.out.println("i=" + i + ", len" + buff.length); 75 throw new RuntimeException(ex); 76 } 77 c = null; 78 } 79 cls = null; 80 System.out.println("Finished " + i + " iterations in " + 81 (System.currentTimeMillis() - startTime) + " ms"); 82 } 83 84 private static byte[] read(File file) { 85 byte buff[] = new byte[(int)(file.length())]; 86 try { 87 DataInputStream din = new DataInputStream(new FileInputStream(file)); 88 din.readFully(buff); 89 din.close(); 90 } catch (IOException ex) { 91 throw new RuntimeException(ex); 92 } 93 return buff; 94 } 95 96 static class MyClassLoader extends ClassLoader { 97 byte buff[]; 98 MyClassLoader(byte buff[]) { 99 this.buff = buff; 100 } 101 102 public Class<?> loadClass() throws ClassNotFoundException { 103 String name = "test.Empty"; 104 try { 105 return defineClass(name, buff, 0, buff.length); 106 } catch (Throwable e) { 107 throw new ClassNotFoundException(name, e); 108 } 109 } 110 } 111 }