1 /*
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   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
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   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).
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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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  23 
  24 /*
  25  * @test TestG1TraceEagerReclaimHumongousObjects
  26  * @bug 8058801 8048179
  27  * @summary Ensure that the output for a G1TraceEagerReclaimHumongousObjects
  28  * includes the expected necessary messages.
  29  * @key gc
  30  * @library /testlibrary
  31  * @modules java.base/jdk.internal.misc
  32  *          java.management
  33  */
  34 
  35 import jdk.test.lib.ProcessTools;
  36 import jdk.test.lib.OutputAnalyzer;
  37 import java.util.LinkedList;
  38 
  39 public class TestG1TraceEagerReclaimHumongousObjects {
  40   public static void main(String[] args) throws Exception {
  41     ProcessBuilder pb = ProcessTools.createJavaProcessBuilder("-XX:+UseG1GC",
  42                                                "-Xms128M",
  43                                                "-Xmx128M",
  44                                                "-Xmn16M",
  45                                                "-XX:G1HeapRegionSize=1M",
  46                                                "-Xlog:gc+phases=trace,gc+humongous=trace",
  47                                                "-XX:+UnlockExperimentalVMOptions",
  48                                                GCWithHumongousObjectTest.class.getName());
  49 
  50     OutputAnalyzer output = new OutputAnalyzer(pb.start());
  51 
  52     // As G1ReclaimDeadHumongousObjectsAtYoungGC is set(default), below logs should be displayed.
  53     output.shouldContain("Humongous Reclaim");
  54     output.shouldContain("Humongous Total");
  55     output.shouldContain("Humongous Candidate");
  56     output.shouldContain("Humongous Reclaimed");
  57 
  58     // As G1TraceReclaimDeadHumongousObjectsAtYoungGC is set and GCWithHumongousObjectTest has humongous objects,
  59     // these logs should be displayed.
  60     output.shouldContain("Live humongous");
  61     output.shouldContain("Dead humongous region");
  62     output.shouldHaveExitValue(0);
  63   }
  64 
  65   static class GCWithHumongousObjectTest {
  66 
  67     public static final int M = 1024*1024;
  68     public static LinkedList<Object> garbageList = new LinkedList<Object>();
  69     // A large object referenced by a static.
  70     static int[] filler = new int[10 * M];
  71 
  72     public static void genGarbage() {
  73       for (int i = 0; i < 32*1024; i++) {
  74         garbageList.add(new int[100]);
  75       }
  76       garbageList.clear();
  77     }
  78 
  79     public static void main(String[] args) {
  80 
  81       int[] large = new int[M];
  82       Object ref = large;
  83 
  84       System.out.println("Creating garbage");
  85       for (int i = 0; i < 100; i++) {
  86         // A large object that will be reclaimed eagerly.
  87         large = new int[6*M];
  88         genGarbage();
  89         // Make sure that the compiler cannot completely remove
  90         // the allocation of the large object until here.
  91         System.out.println(large);
  92       }
  93 
  94       // Keep the reference to the first object alive.
  95       System.out.println(ref);
  96       System.out.println("Done");
  97     }
  98   }
  99 }