1 /*
   2  * Copyright (c) 2012, 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 Humongous.java
  26  * @bug 7168848
  27  * @summary G1: humongous object allocations should initiate marking cycles when necessary
  28  * @library /testlibrary
  29  */
  30 
  31 import com.oracle.java.testlibrary.*;
  32 
  33 public class HumongousAlloc {
  34     private static final int g1HeapSize                       = 200; // MB
  35     private static final int g1HeapRegionSize                 = 1;   // MB
  36     private static final int g1InitiatingHeapOccupancyPercent = 50;  // %
  37 
  38     public static void main(String[] args) throws Exception {
  39         ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(
  40             "-XX:+UseG1GC",
  41             "-Xms" + g1HeapSize + "m",
  42             "-Xmx" + g1HeapSize + "m",
  43             "-XX:G1HeapRegionSize=" + g1HeapRegionSize + "m",
  44             "-XX:InitiatingHeapOccupancyPercent=" + g1InitiatingHeapOccupancyPercent,
  45             "-XX:+PrintGC",
  46             "-XX:+PrintGCDetails",
  47             HumongousAllocRunner.class.getName());
  48 
  49         OutputAnalyzer output = new OutputAnalyzer(pb.start());
  50         output.shouldContain("GC pause (G1 Humongous Allocation) (young) (initial-mark)");
  51         output.shouldNotContain("Full GC");
  52         output.shouldHaveExitValue(0);
  53     }
  54 
  55     static class HumongousAllocRunner {
  56         public static void main(String [] args) throws Exception {
  57             // Object size is 75% of a region
  58             final int g1HumongousObjectSize =
  59                 (int)(g1HeapRegionSize * 1024 * 1024 * 0.75);
  60 
  61             // Number of objects to allocate to go above IHOP
  62             final int g1HumongousObjectAllocations =
  63                 (int)((g1HeapSize * g1InitiatingHeapOccupancyPercent / 100.0) / g1HeapRegionSize) + 1;
  64 
  65             // Allocate
  66             for (int i = 1; i <= g1HumongousObjectAllocations; i++) {
  67                 System.err.println("Allocating humongous object " + i + "/" + g1HumongousObjectAllocations +
  68                                    " of size " + g1HumongousObjectSize + " bytes");
  69                 byte[] dummy = new byte[g1HumongousObjectSize];
  70             }
  71         }
  72     }
  73 }
  74