1 /*
   2  * Copyright (c) 2014, 2015, 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  * @key gc
  27  * @bug 8049831
  28  * @library /testlibrary /test/lib
  29  * @modules java.base/sun.misc
  30  *          java.management
  31  * @build TestG1ClassUnloadingHWM
  32  * @run main ClassFileInstaller sun.hotspot.WhiteBox
  33  *                              sun.hotspot.WhiteBox$WhiteBoxPermission
  34  * @run driver TestG1ClassUnloadingHWM
  35  * @summary Test that -XX:-ClassUnloadingWithConcurrentMark will trigger a Full GC when more than MetaspaceSize metadata is allocated.
  36  */
  37 
  38 import jdk.test.lib.OutputAnalyzer;
  39 import jdk.test.lib.ProcessTools;
  40 import java.util.ArrayList;
  41 import java.util.Arrays;
  42 import sun.hotspot.WhiteBox;
  43 
  44 public class TestG1ClassUnloadingHWM {
  45   private static long MetaspaceSize = 32 * 1024 * 1024;
  46   private static long YoungGenSize  = 32 * 1024 * 1024;
  47 
  48   private static OutputAnalyzer run(boolean enableUnloading) throws Exception {
  49     ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
  50       "-Xbootclasspath/a:.",
  51       "-XX:+UnlockDiagnosticVMOptions",
  52       "-XX:+WhiteBoxAPI",
  53       "-XX:MetaspaceSize=" + MetaspaceSize,
  54       "-Xmn" + YoungGenSize,
  55       "-XX:+UseG1GC",
  56       "-XX:" + (enableUnloading ? "+" : "-") + "ClassUnloadingWithConcurrentMark",
  57       "-XX:+PrintHeapAtGC",
  58       "-XX:+PrintGCDetails",
  59       TestG1ClassUnloadingHWM.AllocateBeyondMetaspaceSize.class.getName(),
  60       "" + MetaspaceSize,
  61       "" + YoungGenSize);
  62     return new OutputAnalyzer(pb.start());
  63   }
  64 
  65   public static OutputAnalyzer runWithG1ClassUnloading() throws Exception {
  66     return run(true);
  67   }
  68 
  69   public static OutputAnalyzer runWithoutG1ClassUnloading() throws Exception {
  70     return run(false);
  71   }
  72 
  73   public static void testWithoutG1ClassUnloading() throws Exception {
  74     // -XX:-ClassUnloadingWithConcurrentMark is used, so we expect a full GC instead of a concurrent cycle.
  75     OutputAnalyzer out = runWithoutG1ClassUnloading();
  76 
  77     out.shouldMatch(".*Full GC.*");
  78     out.shouldNotMatch(".*initial-mark.*");
  79   }
  80 
  81   public static void testWithG1ClassUnloading() throws Exception {
  82     // -XX:+ClassUnloadingWithConcurrentMark is used, so we expect a concurrent cycle instead of a full GC.
  83     OutputAnalyzer out = runWithG1ClassUnloading();
  84 
  85     out.shouldMatch(".*initial-mark.*");
  86     out.shouldNotMatch(".*Full GC.*");
  87   }
  88 
  89   public static void main(String args[]) throws Exception {
  90     testWithG1ClassUnloading();
  91     testWithoutG1ClassUnloading();
  92   }
  93 
  94   public static class AllocateBeyondMetaspaceSize {
  95     public static Object dummy;
  96 
  97     public static void main(String [] args) throws Exception {
  98       if (args.length != 2) {
  99         throw new IllegalArgumentException("Usage: <MetaspaceSize> <YoungGenSize>");
 100       }
 101 
 102       WhiteBox wb = WhiteBox.getWhiteBox();
 103 
 104       // Allocate past the MetaspaceSize limit
 105       long metaspaceSize = Long.parseLong(args[0]);
 106       long allocationBeyondMetaspaceSize  = metaspaceSize * 2;
 107       long metaspace = wb.allocateMetaspace(null, allocationBeyondMetaspaceSize);
 108 
 109       long youngGenSize = Long.parseLong(args[1]);
 110       triggerYoungGCs(youngGenSize);
 111 
 112       wb.freeMetaspace(null, metaspace, metaspace);
 113     }
 114 
 115     public static void triggerYoungGCs(long youngGenSize) {
 116       long approxAllocSize = 32 * 1024;
 117       long numAllocations  = 2 * youngGenSize / approxAllocSize;
 118 
 119       for (long i = 0; i < numAllocations; i++) {
 120         dummy = new byte[(int)approxAllocSize];
 121       }
 122     }
 123   }
 124 }
 125