1 /*
   2  * Copyright (c) 2014, 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 /testlibrary/whitebox
  29  * @build TestCMSClassUnloadingEnabledHWM
  30  * @requires vm.gc=="ConcMarkSweep" | vm.gc=="null"
  31  * @run main ClassFileInstaller sun.hotspot.WhiteBox
  32  *                              sun.hotspot.WhiteBox$WhiteBoxPermission
  33  * @run driver TestCMSClassUnloadingEnabledHWM
  34  * @summary Test that -XX:-CMSClassUnloadingEnabled will trigger a Full GC when more than MetaspaceSize metadata is allocated.
  35  */
  36 
  37 import com.oracle.java.testlibrary.OutputAnalyzer;
  38 import com.oracle.java.testlibrary.ProcessTools;
  39 import java.lang.management.GarbageCollectorMXBean;
  40 import java.lang.management.ManagementFactory;
  41 import java.util.ArrayList;
  42 import java.util.Arrays;
  43 import sun.hotspot.WhiteBox;
  44 
  45 public class TestCMSClassUnloadingEnabledHWM {
  46   private static long MetaspaceSize = 32 * 1024 * 1024;
  47   private static long YoungGenSize  = 32 * 1024 * 1024;
  48 
  49   private static OutputAnalyzer run(boolean enableUnloading) throws Exception {
  50     ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
  51       "-Xbootclasspath/a:.",
  52       "-XX:+UnlockDiagnosticVMOptions",
  53       "-XX:+WhiteBoxAPI",
  54       "-Xmx128m",
  55       "-XX:CMSMaxAbortablePrecleanTime=1",
  56       "-XX:CMSWaitDuration=50",
  57       "-XX:MetaspaceSize=" + MetaspaceSize,
  58       "-Xmn" + YoungGenSize,
  59       "-XX:+UseConcMarkSweepGC",
  60       "-XX:" + (enableUnloading ? "+" : "-") + "CMSClassUnloadingEnabled",
  61       "-XX:+PrintHeapAtGC",
  62       "-XX:+PrintGCDetails",
  63       "-XX:+PrintGCTimeStamps",
  64       TestCMSClassUnloadingEnabledHWM.AllocateBeyondMetaspaceSize.class.getName(),
  65       "" + MetaspaceSize);
  66     return new OutputAnalyzer(pb.start());
  67   }
  68 
  69   public static OutputAnalyzer runWithCMSClassUnloading() throws Exception {
  70     return run(true);
  71   }
  72 
  73   public static OutputAnalyzer runWithoutCMSClassUnloading() throws Exception {
  74     return run(false);
  75   }
  76 
  77   public static void testWithoutCMSClassUnloading() throws Exception {
  78     // -XX:-CMSClassUnloadingEnabled is used, so we expect a full GC instead of a concurrent cycle.
  79     OutputAnalyzer out = runWithoutCMSClassUnloading();
  80 
  81     out.shouldMatch(".*Full GC.*");
  82     out.shouldNotMatch(".*CMS Initial Mark.*");
  83   }
  84 
  85   public static void testWithCMSClassUnloading() throws Exception {
  86     // -XX:+CMSClassUnloadingEnabled is used, so we expect a concurrent cycle instead of a full GC.
  87     OutputAnalyzer out = runWithCMSClassUnloading();
  88 
  89     out.shouldMatch(".*CMS Initial Mark.*");
  90     out.shouldNotMatch(".*Full GC.*");
  91   }
  92 
  93   public static void main(String args[]) throws Exception {
  94     testWithCMSClassUnloading();
  95     testWithoutCMSClassUnloading();
  96   }
  97 
  98   public static class AllocateBeyondMetaspaceSize {
  99     public static void main(String [] args) throws Exception {
 100       if (args.length != 1) {
 101         throw new IllegalArgumentException("Usage: <MetaspaceSize>");
 102       }
 103 
 104       WhiteBox wb = WhiteBox.getWhiteBox();
 105 
 106       // Allocate past the MetaspaceSize limit.
 107       long metaspaceSize = Long.parseLong(args[0]);
 108       long allocationBeyondMetaspaceSize  = metaspaceSize * 2;
 109       long metaspace = wb.allocateMetaspace(null, allocationBeyondMetaspaceSize);
 110 
 111       // Wait for at least one GC to occur. The caller will parse the log files produced.
 112       GarbageCollectorMXBean cmsGCBean = getCMSGCBean();
 113       while (cmsGCBean.getCollectionCount() == 0) {
 114         Thread.sleep(100);
 115       }
 116 
 117       wb.freeMetaspace(null, metaspace, metaspace);
 118     }
 119 
 120     private static GarbageCollectorMXBean getCMSGCBean() {
 121       for (GarbageCollectorMXBean gcBean : ManagementFactory.getGarbageCollectorMXBeans()) {
 122         if (gcBean.getObjectName().toString().equals("java.lang:type=GarbageCollector,name=ConcurrentMarkSweep")) {
 123           return gcBean;
 124         }
 125       }
 126       return null;
 127     }
 128   }
 129 }
 130