--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/runtime/Metaspace/FragmentMetaspace.java	Thu May 23 17:39:32 2013 +0200
@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @library /runtime/testlibrary
+ * @build GeneratedClassLoader
+ * @run main/othervm/timeout=200 FragmentMetaspace
+ */
+
+import java.io.IOException;
+
+/**
+ * Test that tries to fragment the native memory used by class loaders.
+ * This test creates class loaders that load classes of increasing size for every
+ * iteration. By increasing the size of the class meta data needed for every iteration
+ * we stress the subsystem for allocating native memory for meta data.
+ */
+public class FragmentMetaspace {
+
+    public static void main(String... args) {
+        runGrowing(Long.valueOf(System.getProperty("time", "80000")));
+        // try to clean up and unload classes to decrease
+        // class verification time in debug vm
+        System.gc();
+    }
+
+    private static void runGrowing(long time) {
+        long startTime = System.currentTimeMillis();
+        for (int i = 0; System.currentTimeMillis() < startTime + time; ++i) {
+            try {
+                GeneratedClassLoader gcl = new GeneratedClassLoader();
+
+                Class<?> c = gcl.getGeneratedClasses(i, 100)[0];
+                c.newInstance();
+                c = null;
+
+                gcl = null;
+            } catch (IOException|InstantiationException|IllegalAccessException ex) {
+                throw new RuntimeException(ex);
+            }
+        }
+    }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/runtime/Metaspace/FragmentMetaspaceSimple.java	Thu May 23 17:39:32 2013 +0200
@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @library /runtime/testlibrary
+ * @library classes
+ * @build test.Empty ClassUnloadCommon
+ * @run main/othervm/timeout=200 FragmentMetaspaceSimple
+ */
+
+import java.util.ArrayList;
+
+/**
+ * Test that tries to fragment the native memory used by class loaders.
+ * Keeps every other class loader alive in order to fragment the memory space
+ * used to store classes and meta data. Since the memory is probably allocated in
+ * chunks per class loader this will cause a lot of fragmentation if not handled
+ * properly since every other chunk will be unused.
+ */
+public class FragmentMetaspaceSimple {
+    public static void main(String... args) {
+        runSimple(Long.valueOf(System.getProperty("time", "80000")));
+        System.gc();
+    }
+
+    private static void runSimple(long time) {
+        long startTime = System.currentTimeMillis();
+        ArrayList<ClassLoader> cls = new ArrayList<>();
+        for (int i = 0; System.currentTimeMillis() < startTime + time; ++i) {
+            ClassLoader ldr = ClassUnloadCommon.newClassLoader();
+            if (i % 1000 == 0) {
+                cls.clear();
+            }
+            // only keep every other class loader alive
+            if (i % 2 == 1) {
+                cls.add(ldr);
+            }
+            Class<?> c = null;
+            try {
+                c = ldr.loadClass("test.Empty");
+            } catch (ClassNotFoundException ex) {
+                throw new RuntimeException(ex);
+            }
+            c = null;
+        }
+        cls = null;
+    }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/runtime/Metaspace/classes/test/Empty.java	Thu May 23 17:39:32 2013 +0200
@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package test;
+
+public class Empty {
+public String toString() { return "nothing"; }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/runtime/testlibrary/GeneratedClassLoader.java	Thu May 23 17:39:32 2013 +0200
@@ -0,0 +1,202 @@
+/*
+ * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.io.DataInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.PrintWriter;
+import javax.tools.JavaCompiler;
+import javax.tools.ToolProvider;
+
+/**
+ * A class loader that generates new classes.
+ * The generated classes are made by first emitting java sources with nested
+ * static classes, these are then compiled and the class files are read back.
+ * Some efforts are made to make the class instances unique and of not insignificant
+ * size.
+ */
+public class GeneratedClassLoader extends ClassLoader {
+    /**
+     * Holds a pair of class bytecodes and class name (for use with defineClass).
+     */
+    private static class GeneratedClass {
+        public byte[] bytes;
+        public String name;
+        public GeneratedClass(byte[] bytes, String name) {
+            this.bytes = bytes; this.name = name;
+        }
+    }
+
+    /**
+     * Used to uniquely name every class generated.
+     */
+    private static int count = 0;
+    /**
+     * Used to enable/disable keeping the class files and java sources for
+     * the generated classes.
+     */
+    private static boolean deleteFiles = Boolean.parseBoolean(
+        System.getProperty("GeneratedClassLoader.deleteFiles", "true"));
+
+    private static String bigstr =
+        "Lorem ipsum dolor sit amet, consectetur adipiscing elit. "
+        + "In facilisis scelerisque vehicula. Donec congue nisi a "
+        + "leo posuere placerat lobortis felis ultrices. Pellentesque "
+        + "habitant morbi tristique senectus et netus et malesuada "
+        + "fames ac turpis egestas. Nam tristique velit at felis "
+        + "iaculis at tempor sem vestibulum. Sed adipiscing lectus "
+        + "non mi molestie sagittis. Morbi eu purus urna. Nam tempor "
+        + "tristique massa eget semper. Mauris cursus, nulla et ornare "
+        + "vehicula, leo dolor scelerisque metus, sit amet rutrum erat "
+        + "sapien quis dui. Nullam eleifend risus et velit accumsan sed "
+        + "suscipit felis pulvinar. Nullam faucibus suscipit gravida. "
+        + "Pellentesque habitant morbi tristique senectus et netus et "
+        + "malesuada fames ac turpis egestas. Nullam ut massa augue, "
+        + "nec viverra mauris.";
+
+    private static int getNextCount() {
+        return count++;
+    }
+
+    ////// end statics
+
+    private JavaCompiler javac;
+    private String nameBase;
+
+    public GeneratedClassLoader() {
+        javac = ToolProvider.getSystemJavaCompiler();
+        nameBase = "TestSimpleClass";
+    }
+
+    private long getBigValue(int which) {
+        // > 65536 is too large to encode in the bytecode
+        // so this will force us to emit a constant pool entry for this int
+        return (long)which + 65537;
+    }
+
+    private String getBigString(int which) {
+        return bigstr + which;
+    }
+
+    private String getClassName(int count) {
+        return nameBase + count;
+    }
+
+    private String generateSource(int count, int sizeFactor, int numClasses) {
+        StringBuilder sb = new StringBuilder();
+        sb.append("public class ").append(getClassName(count)).append("{\n");
+        for (int j = 0; j < numClasses; ++j) {
+            sb.append("public static class ")
+              .append("Class")
+              .append(j)
+              .append("{\n");
+            for (int i = 0; i < sizeFactor; ++i) {
+                int value = i;
+                sb.append("private long field")
+                  .append(i).append(" = ")
+                  .append(getBigValue(value++))
+                  .append(";\n");
+                sb.append("public long method")
+                  .append(i)
+                  .append("() {\n");
+                sb.append("return ")
+                  .append(getBigValue(value++))
+                  .append(";");
+                sb.append("}\n");
+                sb.append("private String str").append(i)
+                  .append(" = \"")
+                  .append(getBigString(i))
+                  .append("\";");
+            }
+            sb.append("\n}");
+        }
+        sb.append("\n}");
+        return sb.toString();
+    }
+
+    private GeneratedClass[] getGeneratedClass(int sizeFactor, int numClasses) throws IOException {
+        int uniqueCount = getNextCount();
+        String src = generateSource(uniqueCount, sizeFactor, numClasses);
+        String className = getClassName(uniqueCount);
+        File file = new File(className + ".java");
+        try (PrintWriter pw = new PrintWriter(new FileWriter(file))) {
+            pw.append(src);
+            pw.flush();
+        }
+        int exitcode = javac.run(null, null, null, file.getCanonicalPath());
+        if (exitcode != 0) {
+            throw new RuntimeException("javac failure when compiling: " +
+                    file.getCanonicalPath());
+        } else {
+            if (deleteFiles) {
+                file.delete();
+            }
+        }
+        GeneratedClass[] gc = new GeneratedClass[numClasses];
+        for (int i = 0; i < numClasses; ++i) {
+            String name = className + "$" + "Class" + i;
+            File classFile = new File(name + ".class");
+            byte[] bytes;
+            try (DataInputStream dis = new DataInputStream(new FileInputStream(classFile))) {
+                bytes = new byte[dis.available()];
+                dis.readFully(bytes);
+            }
+            if (deleteFiles) {
+                classFile.delete();
+            }
+            gc[i] = new GeneratedClass(bytes, name);
+        }
+        if (deleteFiles) {
+            new File(className + ".class").delete();
+        }
+        return gc;
+    }
+
+    /**
+     * Generate a single class, compile it and load it.
+     * @param sizeFactor Fuzzy measure of how large the class should be.
+     * @return the Class instance.
+     * @throws IOException
+     */
+    public Class<?> generateClass(int sizeFactor) throws IOException {
+        return getGeneratedClasses(sizeFactor, 1)[0];
+    }
+
+    /**
+     * Generate several classes, compile and load them.
+     * @param sizeFactor Fuzzy measure of how large each class should be.
+     * @param numClasses The number of classes to create
+     * @return an array of the Class instances.
+     * @throws IOException
+     */
+    public Class<?>[] getGeneratedClasses(int sizeFactor, int numClasses) throws IOException {
+        GeneratedClass[] gc = getGeneratedClass(sizeFactor, numClasses);
+        Class<?>[] classes = new Class[numClasses];
+        for (int i = 0; i < numClasses; ++i) {
+            classes[i] = defineClass(gc[i].name, gc[i].bytes, 0 , gc[i].bytes.length);
+        }
+        return classes;
+    }
+}