1 /*
   2  * Copyright (c) 2013, 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 TestObjectAlignment
  26  * @key gc
  27  * @bug 8021823
  28  * @summary G1: Concurrent marking crashes with -XX:ObjectAlignmentInBytes>=32 in 64bit VMs
  29  * @library /testlibrary
  30  * @run main/othervm TestObjectAlignment
  31  */
  32 
  33 import com.oracle.java.testlibrary.ProcessTools;
  34 import com.oracle.java.testlibrary.OutputAnalyzer;
  35 
  36 public class TestObjectAlignment {
  37 
  38   private static boolean runsOn32bit() {
  39     return System.getProperty("sun.arch.data.model").equals("32");
  40   }
  41 
  42   public static void runTest(int objectAlignment) throws Exception {
  43     ProcessBuilder pb = ProcessTools.createJavaProcessBuilder("-XX:+UseG1GC",
  44                                                               "-Xmx20M",
  45                                                               "-XX:+ExplicitGCInvokesConcurrent",
  46                                                               "-XX:ObjectAlignmentInBytes=" + objectAlignment,
  47                                                               TestObjectAlignmentTest.class.getName());
  48     OutputAnalyzer output = new OutputAnalyzer(pb.start());
  49     output.shouldHaveExitValue(0);
  50   }
  51 
  52   public static void main(String[] args) throws Exception {
  53     if (runsOn32bit()) {
  54       // 32 bit VMs do not allow setting ObjectAlignmentInBytes.
  55       return;
  56     }
  57     runTest(8);
  58     runTest(16);
  59     runTest(32);
  60     runTest(64);
  61     runTest(128);
  62     runTest(256);
  63   }
  64 
  65   static class TestObjectAlignmentTest {
  66     static byte[] garbage;
  67 
  68     public static void main(String [] args) {
  69       for (int i = 0; i < 100; i++) {
  70         garbage = new byte[1000];
  71         System.gc();
  72       }
  73     }
  74   }
  75 }