1/* 2 * Copyright (c) 2016, 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 24package gc.g1.humongousObjects; 25 26import jdk.test.lib.Utils; 27import sun.hotspot.WhiteBox; 28 29import java.util.LinkedList; 30import java.util.List; 31import java.util.Random; 32import java.util.stream.Collectors; 33 34/** 35 * @test TestNoAllocationsInHRegions 36 * @summary Checks that no additional allocations are made in humongous regions 37 * @requires vm.gc.G1 38 * @library /test/lib / 39 * @modules java.management java.base/jdk.internal.misc 40 * @build sun.hotspot.WhiteBox 41 * @run driver ClassFileInstaller sun.hotspot.WhiteBox 42 * sun.hotspot.WhiteBox$WhiteBoxPermission 43 * 44 * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. 45 * -XX:G1HeapRegionSize=1M -Xms200m -Xmx200m -XX:MaxTenuringThreshold=0 46 * -Xlog:gc=trace:file=TestNoAllocationsInHRegions10.log 47 * gc.g1.humongousObjects.TestNoAllocationsInHRegions 30 10 48 * 49 * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. 50 * -XX:G1HeapRegionSize=1M -Xms200m -Xmx200m -XX:MaxTenuringThreshold=0 51 * -Xlog:gc=trace:file=TestNoAllocationsInHRegions50.log 52 * gc.g1.humongousObjects.TestNoAllocationsInHRegions 30 50 53 * 54 * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. 55 * -XX:G1HeapRegionSize=1M -Xms200m -Xmx200m -XX:MaxTenuringThreshold=0 56 * -Xlog:gc=trace:file=TestNoAllocationsInHRegions70.log 57 * gc.g1.humongousObjects.TestNoAllocationsInHRegions 30 70 58 */ 59public class TestNoAllocationsInHRegions { 60 private static final WhiteBox WB = WhiteBox.getWhiteBox(); 61 private static final Random RND = Utils.getRandomInstance(); 62 private static final int G1_REGION_SIZE = WB.g1RegionSize(); 63 private static final int[] HUMONGOUS_SIZES = {G1_REGION_SIZE / 2, G1_REGION_SIZE + 1, G1_REGION_SIZE * 2 + 1}; 64 private static final int ALLOC_THREAD_COUNT = 5; 65 66 // We fill specified part of heap with humongous objects - we need public static to prevent escape analysis to 67 // collect this field 68 public static LinkedList<byte[]> humongousAllocations = new LinkedList<>(); 69 70 private static volatile boolean shouldStop = false; 71 private static volatile Error error = null; 72 73 static class Allocator implements Runnable { 74 75 private final List<byte[]> liveObjects = new LinkedList<>(); 76 private int usedMemory = 0; 77 public final Runnable[] actions; 78 79 /** 80 * Maximum size of simple allocation 81 */ 82 private static final int MAX_ALLOCATION_SIZE = (int) (G1_REGION_SIZE / 2 * 0.9); 83 84 /** 85 * Maximum size of dead (i.e. one which is made unreachable right after allocation) object 86 */ 87 private static final int DEAD_OBJECT_MAX_SIZE = G1_REGION_SIZE / 10; 88 89 public Allocator(int maxAllocationMemory) { 90 91 actions = new Runnable[]{ 92 // Allocation 93 () -> { 94 if (maxAllocationMemory - usedMemory != 0) { 95 int arraySize = RND.nextInt(Math.min(maxAllocationMemory - usedMemory, 96 MAX_ALLOCATION_SIZE)); 97 98 if (arraySize != 0) { 99 byte[] allocation = new byte[arraySize]; 100 liveObjects.add(allocation); 101 usedMemory += arraySize; 102 103 // Sanity check 104 if (WB.g1IsHumongous(allocation)) { 105 String errorMessage = String.format("Test Bug: Byte array of size" 106 + " %d is expected to be non-humongous but it is humongous", 107 allocation.length); 108 109 System.out.println(errorMessage); 110 error = new Error(errorMessage); 111 shouldStop = true; 112 } 113 114 // Test check 115 if (WB.g1BelongsToHumongousRegion(WB.getObjectAddress(allocation))) { 116 String errorMessage = String.format("Non-humongous allocation of byte array of " 117 + "length %d and size %d with address %d was made in Humongous Region", 118 allocation.length, WB.getObjectSize(allocation), 119 WB.getObjectAddress(allocation)); 120 121 System.out.println(errorMessage); 122 error = new Error(errorMessage); 123 shouldStop = true; 124 } 125 } 126 } 127 }, 128 129 // Deallocation 130 () -> { 131 if (liveObjects.size() != 0) { 132 int elementNum = RND.nextInt(liveObjects.size()); 133 int shouldFree = liveObjects.get(elementNum).length; 134 liveObjects.remove(elementNum); 135 usedMemory -= shouldFree; 136 } 137 }, 138 139 // Dead object allocation 140 () -> { 141 int size = RND.nextInt(DEAD_OBJECT_MAX_SIZE); 142 byte[] deadObject = new byte[size]; 143 }, 144 145 // Check 146 () -> { 147 List<byte[]> wrongHumongousAllocations = liveObjects.stream() 148 .filter(WB::g1IsHumongous) 149 .collect(Collectors.toList()); 150 151 if (wrongHumongousAllocations.size() > 0) { 152 wrongHumongousAllocations.stream().forEach(a -> 153 System.out.format("Non-humongous allocation of byte array of length %d and" 154 + " size %d with address %d was made in Humongous Region", 155 a.length, WB.getObjectSize(a), WB.getObjectAddress(a))); 156 error = new Error("Some non-humongous allocations were made to humongous region"); 157 shouldStop = true; 158 } 159 } 160 }; 161 } 162 163 @Override 164 public void run() { 165 while (!shouldStop) { 166 actions[RND.nextInt(actions.length)].run(); 167 Thread.yield(); 168 } 169 } 170 } 171 172 public static void main(String[] args) { 173 if (args.length != 2) { 174 throw new Error("Test Bug: Expected duration (in seconds) and percent of allocated regions were not " 175 + "provided as command line argument"); 176 } 177 178 // test duration 179 long duration = Integer.parseInt(args[0]) * 1000L; 180 // part of heap preallocated with humongous objects (in percents) 181 int percentOfAllocatedHeap = Integer.parseInt(args[1]); 182 183 long startTime = System.currentTimeMillis(); 184 185 long initialFreeRegionsCount = WB.g1NumFreeRegions(); 186 int regionsToAllocate = (int) ((double) initialFreeRegionsCount / 100.0 * percentOfAllocatedHeap); 187 long freeRegionLeft = initialFreeRegionsCount - regionsToAllocate; 188 189 System.out.println("Regions to allocate: " + regionsToAllocate + "; regions to left free: " + freeRegionLeft); 190 191 int maxMemoryPerAllocThread = (int) ((Runtime.getRuntime().freeMemory() / 100.0 192 * (100 - percentOfAllocatedHeap)) / ALLOC_THREAD_COUNT * 0.5); 193 194 System.out.println("Using " + maxMemoryPerAllocThread / 1024 + "KB for each of " + ALLOC_THREAD_COUNT 195 + " allocation threads"); 196 197 while (WB.g1NumFreeRegions() > freeRegionLeft) { 198 try { 199 humongousAllocations.add(new byte[HUMONGOUS_SIZES[RND.nextInt(HUMONGOUS_SIZES.length)]]); 200 } catch (OutOfMemoryError oom) { 201 //We got OOM trying to fill heap with humongous objects 202 //It probably means that heap is fragmented which is strange since the test logic should avoid it 203 System.out.println("Warning: OOM while allocating humongous objects - it likely means " 204 + "that heap is fragmented"); 205 break; 206 } 207 } 208 209 System.out.println("Initial free regions " + initialFreeRegionsCount + "; Free regions left " 210 + WB.g1NumFreeRegions()); 211 212 LinkedList<Thread> threads = new LinkedList<>(); 213 214 for (int i = 0; i < ALLOC_THREAD_COUNT; i++) { 215 threads.add(new Thread(new Allocator(maxMemoryPerAllocThread))); 216 } 217 218 threads.stream().forEach(Thread::start); 219 220 while ((System.currentTimeMillis() - startTime < duration) && error == null) { 221 Thread.yield(); 222 } 223 224 shouldStop = true; 225 System.out.println("Finished test"); 226 if (error != null) { 227 throw error; 228 } 229 } 230} 231