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 /test/lib
  29  * @modules java.base/jdk.internal.misc
  30  *          java.management
  31  * @build sun.hotspot.WhiteBox
  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.process.OutputAnalyzer;
  39 import jdk.test.lib.process.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       "-Xlog:gc",
  58       TestG1ClassUnloadingHWM.AllocateBeyondMetaspaceSize.class.getName(),
  59       "" + MetaspaceSize,
  60       "" + YoungGenSize);
  61     return new OutputAnalyzer(pb.start());
  62   }
  63 
  64   public static OutputAnalyzer runWithG1ClassUnloading() throws Exception {
  65     return run(true);
  66   }
  67 
  68   public static OutputAnalyzer runWithoutG1ClassUnloading() throws Exception {
  69     return run(false);
  70   }
  71 
  72   public static void testWithoutG1ClassUnloading() throws Exception {
  73     // -XX:-ClassUnloadingWithConcurrentMark is used, so we expect a full GC instead of a concurrent cycle.
  74     OutputAnalyzer out = runWithoutG1ClassUnloading();
  75 
  76     out.shouldMatch(".*Pause Full.*");
  77     out.shouldNotMatch(".*Pause Initial Mark.*");
  78   }
  79 
  80   public static void testWithG1ClassUnloading() throws Exception {
  81     // -XX:+ClassUnloadingWithConcurrentMark is used, so we expect a concurrent cycle instead of a full GC.
  82     OutputAnalyzer out = runWithG1ClassUnloading();
  83 
  84     out.shouldMatch(".*Pause Initial Mark.*");
  85     out.shouldNotMatch(".*Pause Full.*");
  86   }
  87 
  88   public static void main(String args[]) throws Exception {
  89     testWithG1ClassUnloading();
  90     testWithoutG1ClassUnloading();
  91   }
  92 
  93   public static class AllocateBeyondMetaspaceSize {
  94     public static Object dummy;
  95 
  96     public static void main(String [] args) throws Exception {
  97       if (args.length != 2) {
  98         throw new IllegalArgumentException("Usage: <MetaspaceSize> <YoungGenSize>");
  99       }
 100 
 101       WhiteBox wb = WhiteBox.getWhiteBox();
 102 
 103       // Allocate past the MetaspaceSize limit
 104       long metaspaceSize = Long.parseLong(args[0]);
 105       long allocationBeyondMetaspaceSize  = metaspaceSize * 2;
 106       long metaspace = wb.allocateMetaspace(null, allocationBeyondMetaspaceSize);
 107 
 108       long youngGenSize = Long.parseLong(args[1]);
 109       triggerYoungGCs(youngGenSize);
 110 
 111       wb.freeMetaspace(null, metaspace, metaspace);
 112     }
 113 
 114     public static void triggerYoungGCs(long youngGenSize) {
 115       long approxAllocSize = 32 * 1024;
 116       long numAllocations  = 2 * youngGenSize / approxAllocSize;
 117 
 118       for (long i = 0; i < numAllocations; i++) {
 119         dummy = new byte[(int)approxAllocSize];
 120       }
 121     }
 122   }
 123 }
 124