1 /* 2 * Copyright (c) 2015, 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 package jdk.test.lib; 25 26 import java.util.LinkedList; 27 import java.util.concurrent.Callable; 28 29 /** 30 * Helper class which allocates memory. 31 * 32 * Typical usage: 33 * <pre> 34 * {@code 35 * AllocationHelper allocator = new AllocationHelper(MAX_ITERATIONS, ARRAY_LENGTH, CHUNK_SIZE, 36 * () -> (verifier())); 37 * // Allocate byte[CHUNK_SIZE] ARRAY_LENGTH times. Total allocated bytes will be CHUNK_SIZE * ARRAY_LENGTH + refs length. 38 * // Then invoke verifier and iterate MAX_ITERATIONS times. 39 * allocator.allocateMemoryAndVerify(); 40 * } 41 * </pre> 42 */ 43 public final class AllocationHelper { 44 45 private final int arrayLength; 46 private final int maxIterations; 47 private final int chunkSize; 48 49 // garbageStorage is used to store link to garbage to prevent optimization. 50 private static Object garbageStorage; 51 private byte garbage[][]; 52 private final Callable<?> verifierInstance; 53 54 /** 55 * Create an AllocationHelper with specified iteration count, array length, chunk size and verifier. 56 * 57 * @param maxIterations 58 * @param arrayLength 59 * @param chunkSize 60 * @param verifier - Callable instance which will be invoked after all allocation cycle. Can be null; 61 */ 62 public AllocationHelper(int maxIterations, int arrayLength, int chunkSize, Callable<?> verifier) { 63 if ((arrayLength <= 0) || (maxIterations <= 0) || (chunkSize <= 0)) { 64 throw new IllegalArgumentException("maxIterations, arrayLength and chunkSize should be greater then 0."); 65 } 66 this.arrayLength = arrayLength; 67 this.maxIterations = maxIterations; 68 this.chunkSize = chunkSize; 69 verifierInstance = verifier; 70 garbage = new byte[this.arrayLength][]; 71 garbageStorage = garbage; 72 } 73 74 private void allocateMemoryOneIteration() { 75 for (int j = 0; j < arrayLength; j++) { 76 garbage[j] = new byte[chunkSize]; 77 } 78 } 79 80 /** 81 * Allocate memory and invoke Verifier during all iteration. 82 * 83 * @throws java.lang.Exception 84 */ 85 public void allocateMemoryAndVerify() throws Exception { 86 for (int i = 0; i < maxIterations; i++) { 87 allocateMemoryOneIteration(); 88 if (verifierInstance != null) { 89 verifierInstance.call(); 90 } 91 } 92 } 93 94 /** 95 * The same as allocateMemoryAndVerify() but hides OOME 96 * 97 * @throws Exception 98 */ 99 public void allocateMemoryAndVerifyNoOOME() throws Exception { 100 try { 101 allocateMemoryAndVerify(); 102 } catch (OutOfMemoryError e) { 103 // exit on OOME 104 } 105 } 106 107 /** 108 * Release link to allocated garbage to make it available for further GC 109 */ 110 public void release() { 111 if (garbage != null) { 112 garbage = null; 113 garbageStorage = null; 114 } 115 } 116 }