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 TestSoftReferencesBehaviorOnOOME
  26  * @key gc
  27  * @summary Tests that all SoftReferences has been cleared at time of OOM.
  28  * @library /testlibrary
  29  * @build TestSoftReferencesBehaviorOnOOME
  30  * @run main/othervm -Xmx128m TestSoftReferencesBehaviorOnOOME 512 2k
  31  * @run main/othervm -Xmx128m TestSoftReferencesBehaviorOnOOME 128k 256k
  32  * @run main/othervm -Xmx128m TestSoftReferencesBehaviorOnOOME 2k 32k 10
  33  */
  34 import java.util.*;
  35 import com.oracle.java.testlibrary.Utils;
  36 import java.lang.ref.SoftReference;
  37 import java.util.LinkedList;
  38 
  39 public class TestSoftReferencesBehaviorOnOOME {
  40 
  41     private static final Random rndGenerator = new Random();
  42 
  43     public static void main(String[] args) {
  44         int semiRefAllocFrequency = DEFAULT_FREQUENCY;
  45         long minSize = DEFAULT_MIN_SIZE,
  46                 maxSize = DEFAULT_MAX_SIZE;
  47 
  48         if ( args.length >= 3 ) {
  49             semiRefAllocFrequency = Integer.parseInt(args[2]);
  50         }
  51 
  52         if ( args.length >= 2) {
  53             maxSize = getBytesCount(args[1]);
  54         }
  55 
  56         if ( args.length >= 1) {
  57             minSize = getBytesCount(args[0]);
  58         }
  59 
  60         new TestSoftReferencesBehaviorOnOOME().softReferencesOom(minSize, maxSize, semiRefAllocFrequency);
  61     }
  62 
  63     /**
  64      * Test that all SoftReferences has been cleared at time of OOM.
  65      */
  66     void softReferencesOom(long minSize, long maxSize, int semiRefAllocFrequency) {
  67         System.out.format( "minSize = %d, maxSize = %d, freq = %d%n", minSize, maxSize, semiRefAllocFrequency );
  68         long counter = 0;
  69 
  70         long multiplier = maxSize - minSize;
  71         LinkedList<SoftReference> arrSoftRefs = new LinkedList();
  72         LinkedList arrObjects = new LinkedList();
  73         long numberOfNotNulledObjects = 0;
  74         long oomSoftArraySize = 0;
  75 
  76         try {
  77             while (true) {
  78                 // Keep every Xth object to make sure we hit OOM pretty fast
  79                 if (counter % semiRefAllocFrequency != 0) {
  80                     long allocationSize = ((int) (rndGenerator.nextDouble() * multiplier))
  81                             + minSize;
  82                     arrObjects.add(new byte[(int)allocationSize]);
  83                 } else {
  84                     arrSoftRefs.add(new SoftReference(new Object()));
  85                 }
  86 
  87                 counter++;
  88                 if (counter == Long.MAX_VALUE) {
  89                     counter = 0;
  90                 }
  91             }
  92         } catch (OutOfMemoryError oome) {
  93             // Clear allocated ballast, so we don't get another OOM.
  94 
  95             arrObjects = null;
  96 
  97             // Get the number of soft refs first, so we don't trigger
  98             // another OOM.
  99             oomSoftArraySize = arrSoftRefs.size();
 100 
 101             for (SoftReference sr : arrSoftRefs) {
 102                 Object o = sr.get();
 103 
 104                 if (o != null) {
 105                     numberOfNotNulledObjects++;
 106                 }
 107             }
 108 
 109             // Make sure we clear all refs before we return failure
 110             arrSoftRefs = null;
 111 
 112             if (numberOfNotNulledObjects > 0) {
 113                 throw new RuntimeException(numberOfNotNulledObjects + " out of "
 114                         + oomSoftArraySize + " SoftReferences was not "
 115                         + "null at time of OutOfMemoryError");
 116             }
 117         } finally {
 118             arrSoftRefs = null;
 119             arrObjects = null;
 120         }
 121     }
 122 
 123     private static final long getBytesCount(String arg) {
 124         String postfixes = "kMGT";
 125         long mod = 1;
 126 
 127         if (arg.trim().length() >= 2) {
 128             mod = postfixes.indexOf(
 129                     arg.trim().charAt(arg.length() - 1)
 130             );
 131 
 132             if (mod != -1) {
 133                 mod = (long) Math.pow(1024, mod+1);
 134                 arg = arg.substring(0, arg.length() - 1);
 135             } else {
 136                 mod = 1; // 10^0
 137             }
 138         }
 139 
 140         return Long.parseLong(arg) * mod;
 141     }
 142 
 143     private static final long DEFAULT_MIN_SIZE = 512;
 144     private static final long DEFAULT_MAX_SIZE = 1024;
 145     private static final int DEFAULT_FREQUENCY = 4;
 146 }