1 /* 2 * Copyright (c) 2002, 2020, 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 /* 26 * @test 27 * @key gc randomness 28 * 29 * @summary converted from VM Testbase gc/gctests/nativeGC05. 30 * VM Testbase keywords: [gc] 31 * VM Testbase readme: 32 * ******************************** 33 * set TIMEOUT = 20 34 * ******************************* 35 * This test creates a 2 dimensional matrix of (100X100)10,000 elements. 36 * Each element in this matrix houses the address of a "Cell" that 37 * occupies about 100 bytes. The total memory occupied by this structure is 38 * about 1M. 39 * Once this structure, has been built, 5 threads are let loose that 40 * randomly choose an element in this matrix and set its contents to null 41 * effectively creating 100bytes of garbage. The threads continue to act 42 * until all 5 threads combined have "nulled out" half the cells in the matrix, 43 * which amounts to 0.5Meg of garbage. The indices of each "nulled out" 44 * cell is stored in a stack. This information is later used during 45 * the refilling stage by the native function, kickOffRefiller(); 46 * The native function, kickOffRefiller() refills all the lacunae in the 47 * matrix with new cells. 48 * This process of nulling out" and refilling is repeated 50 times. 49 * Every iteration produces 0.5 Meg 50 * of garbage. The maximum amount of live memory at use at any time is 1Meg. 51 * If no garbage collection takes place during any of the ten iterations, 52 * the total amount(live + garbage) of heap space consumed at the end 53 * of the program is 0.5*50 + 1 = 26Meg. 54 * The test fails if an OutOfMemory Exception is thrown. 55 * ----------------------------- -------- 56 * | | | | | | | 100 | 57 * | | | | | *--|------>| bytes| 58 * | | | | | | -------- 59 * ----------------------------- 60 * . . . . . . 61 * . . . . . . 62 * . . . . . . 63 * . 64 * | | | | | | 65 * | | | | | | 66 * | | | | | | 67 * ------------------------------ 68 * | | | | | | 69 * | | | | | | 70 * | | | | | | 71 * ------------------------------ 72 * | | | | | | 73 * | | | | | | 74 * | | | | | | 75 * ------------------------------ 76 * | | | | | | 77 * | | | | | | 78 * | | | | | | 79 * ----------------------------- 80 * 81 * @library /vmTestbase 82 * /test/lib 83 * @run driver jdk.test.lib.FileInstaller . . 84 * @run main/othervm/native gc.gctests.nativeGC05.nativeGC05 85 */ 86 87 package gc.gctests.nativeGC05; 88 89 import nsk.share.TestFailure; 90 import nsk.share.test.*; 91 import nsk.share.gc.*; 92 import java.util.Stack; 93 94 public class nativeGC05 extends GCTestBase { 95 private final int threadCount = 5; 96 private Stack<IndexPair> emptiedLocations = new Stack<IndexPair>(); 97 private Matrix matrix = new Matrix(100, 100); 98 99 public native void kickOffRefillers(Matrix matrix, Stack s); 100 101 private class CellEmptier extends Thread { 102 public CellEmptier() { 103 } 104 105 boolean keepEmptying(){ 106 int numberOfCells; 107 int matrixSize; 108 109 matrixSize = matrix.returnArrayBound(); 110 numberOfCells = (matrixSize + 1) * (matrixSize + 1) ; 111 if (matrix.getCellCount() < numberOfCells/2) 112 return true; 113 else 114 return false; 115 } 116 117 public void run() { 118 int i, j, matrixSize,emptyCells; 119 120 matrixSize = matrix.returnArrayBound(); 121 while (keepEmptying()) { 122 i = LocalRandom.nextInt(0, matrixSize); 123 j = LocalRandom.nextInt(0, matrixSize); 124 emptiedLocations.push(new IndexPair(i,j)); //Register empty node 125 matrix.clear(i,j); 126 } 127 } 128 } 129 130 131 private class StackDump extends Thread { 132 public StackDump() { 133 } 134 135 public void run() { 136 int emptyCells; 137 138 while (true) { 139 emptyCells = emptiedLocations.size(); 140 System.out.println("Number of empty cells = " + emptyCells); 141 } 142 } 143 } 144 145 146 public void run() { 147 Thread emptierArray[] = new Thread[threadCount]; 148 int count = 0; 149 int memoryReserve[] = new int[10000]; 150 151 //Create 5 CellEmptier Threads. There should be about 1Meg of 152 // created garbage by the times these 5 threads return. 153 154 try { 155 while (count < 50) { 156 for (int i = 0; i < threadCount; i++) 157 emptierArray[i] = new CellEmptier(); 158 for (int i = 0; i < threadCount; i++) 159 emptierArray[i].start(); 160 161 // wait for "emptier" threads to finish their job 162 163 int i = 0; 164 while (i < threadCount) { 165 try { 166 emptierArray[i].join(); 167 } catch(InterruptedException e) { 168 } 169 i++; 170 } 171 172 // Now start refilling. 173 174 kickOffRefillers(matrix, emptiedLocations); 175 176 // reset count of cells emptied out and start again. 177 matrix.resetCellCount(); 178 count++; 179 } 180 } catch (OutOfMemoryError e) { 181 memoryReserve = null; 182 System.gc(); 183 throw new TestFailure("Test Failed at " + count + "th iteration."); 184 } 185 System.out.println("Test passed."); 186 } 187 188 public static void main(String args[]) { 189 GC.runTest(new nativeGC05(), args); 190 } 191 192 static { 193 System.loadLibrary("nativeGC05"); 194 } 195 }