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 */ 24 25 package gc.g1.humongousObjects; 26 27 import jdk.test.lib.Utils; 28 import sun.hotspot.WhiteBox; 29 30 import java.util.LinkedList; 31 import java.util.List; 32 import java.util.Random; 33 import java.util.stream.Collectors; 34 35 /** 36 * @test TestNoAllocationsInHRegions 37 * @summary Checks that no additional allocations are made in humongous regions 38 * @requires vm.gc.G1 39 * @library /testlibrary /test/lib / 40 * @modules java.management java.base/jdk.internal.misc 41 * @build sun.hotspot.WhiteBox 42 * gc.testlibrary.Helpers 43 * gc.g1.humongousObjects.TestNoAllocationsInHRegions 44 * 45 * @run driver ClassFileInstaller sun.hotspot.WhiteBox 46 * sun.hotspot.WhiteBox$WhiteBoxPermission 47 * 48 * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. 49 * -XX:G1HeapRegionSize=1M -Xms200m -Xmx200m -XX:MaxTenuringThreshold=0 50 * -Xlog:gc=trace:file=TestNoAllocationsInHRegions10.log 51 * gc.g1.humongousObjects.TestNoAllocationsInHRegions 30 10 52 * 53 * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. 54 * -XX:G1HeapRegionSize=1M -Xms200m -Xmx200m -XX:MaxTenuringThreshold=0 55 * -Xlog:gc=trace:file=TestNoAllocationsInHRegions50.log 56 * gc.g1.humongousObjects.TestNoAllocationsInHRegions 30 50 57 * 58 * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. 59 * -XX:G1HeapRegionSize=1M -Xms200m -Xmx200m -XX:MaxTenuringThreshold=0 60 * -Xlog:gc=trace:file=TestNoAllocationsInHRegions70.log 61 * gc.g1.humongousObjects.TestNoAllocationsInHRegions 30 70 62 */ 63 public class TestNoAllocationsInHRegions { 64 private static final WhiteBox WB = WhiteBox.getWhiteBox(); 65 private static final Random RND = Utils.getRandomInstance(); 66 private static final int G1_REGION_SIZE = WB.g1RegionSize(); 67 private static final int[] HUMONGOUS_SIZES = {G1_REGION_SIZE / 2, G1_REGION_SIZE + 1, G1_REGION_SIZE * 2 + 1}; 68 private static final int ALLOC_THREAD_COUNT = 5; 69 70 // We fill specified part of heap with humongous objects - we need public static to prevent escape analysis to 71 // collect this field 72 public static LinkedList<byte[]> humongousAllocations = new LinkedList<>(); 73 74 private static volatile boolean shouldStop = false; 75 private static volatile Error error = null; 76 77 static class Allocator implements Runnable { 78 79 private final List<byte[]> liveObjects = new LinkedList<>(); 80 private int usedMemory = 0; 81 public final Runnable[] actions; 82 83 /** 84 * Maximum size of simple allocation 85 */ 86 private static final int MAX_ALLOCATION_SIZE = (int) (G1_REGION_SIZE / 2 * 0.9); 87 88 /** 89 * Maximum size of dead (i.e. one which is made unreachable right after allocation) object 90 */ 91 private static final int DEAD_OBJECT_MAX_SIZE = G1_REGION_SIZE / 10; 92 93 public Allocator(int maxAllocationMemory) { 94 95 actions = new Runnable[]{ 96 // Allocation 97 () -> { 98 if (maxAllocationMemory - usedMemory != 0) { 99 int arraySize = RND.nextInt(Math.min(maxAllocationMemory - usedMemory, 100 MAX_ALLOCATION_SIZE)); 101 102 if (arraySize != 0) { 103 byte[] allocation = new byte[arraySize]; 104 liveObjects.add(allocation); 105 usedMemory += arraySize; 106 107 // Sanity check 108 if (WB.g1IsHumongous(allocation)) { 109 String errorMessage = String.format("Test Bug: Byte array of size" 110 + " %d is expected to be non-humongous but it is humongous", 111 allocation.length); 112 113 System.out.println(errorMessage); 114 error = new Error(errorMessage); 115 shouldStop = true; 116 } 117 118 // Test check 119 if (WB.g1BelongsToHumongousRegion(WB.getObjectAddress(allocation))) { 120 String errorMessage = String.format("Non-humongous allocation of byte array of " 121 + "length %d and size %d with address %d was made in Humongous Region", 122 allocation.length, WB.getObjectSize(allocation), 123 WB.getObjectAddress(allocation)); 124 125 System.out.println(errorMessage); 126 error = new Error(errorMessage); 127 shouldStop = true; 128 } 129 } 130 } 131 }, 132 133 // Deallocation 134 () -> { 135 if (liveObjects.size() != 0) { 136 int elementNum = RND.nextInt(liveObjects.size()); 137 int shouldFree = liveObjects.get(elementNum).length; 138 liveObjects.remove(elementNum); 139 usedMemory -= shouldFree; 140 } 141 }, 142 143 // Dead object allocation 144 () -> { 145 int size = RND.nextInt(DEAD_OBJECT_MAX_SIZE); 146 byte[] deadObject = new byte[size]; 147 }, 148 149 // Check 150 () -> { 151 List<byte[]> wrongHumongousAllocations = liveObjects.stream() 152 .filter(WB::g1IsHumongous) 153 .collect(Collectors.toList()); 154 155 if (wrongHumongousAllocations.size() > 0) { 156 wrongHumongousAllocations.stream().forEach(a -> 157 System.out.format("Non-humongous allocation of byte array of length %d and" 158 + " size %d with address %d was made in Humongous Region", 159 a.length, WB.getObjectSize(a), WB.getObjectAddress(a))); 160 error = new Error("Some non-humongous allocations were made to humongous region"); 161 shouldStop = true; 162 } 163 } 164 }; 165 } 166 167 @Override 168 public void run() { 169 while (!shouldStop) { 170 actions[RND.nextInt(actions.length)].run(); 171 Thread.yield(); 172 } 173 } 174 } 175 176 public static void main(String[] args) { 177 if (args.length != 2) { 178 throw new Error("Test Bug: Expected duration (in seconds) and percent of allocated regions were not " 179 + "provided as command line argument"); 180 } 181 182 // test duration 183 long duration = Integer.parseInt(args[0]) * 1000L; 184 // part of heap preallocated with humongous objects (in percents) 185 int percentOfAllocatedHeap = Integer.parseInt(args[1]); 186 187 long startTime = System.currentTimeMillis(); 188 189 long initialFreeRegionsCount = WB.g1NumFreeRegions(); 190 int regionsToAllocate = (int) ((double) initialFreeRegionsCount / 100.0 * percentOfAllocatedHeap); 191 long freeRegionLeft = initialFreeRegionsCount - regionsToAllocate; 192 193 System.out.println("Regions to allocate: " + regionsToAllocate + "; regions to left free: " + freeRegionLeft); 194 195 int maxMemoryPerAllocThread = (int) ((Runtime.getRuntime().freeMemory() / 100.0 196 * (100 - percentOfAllocatedHeap)) / ALLOC_THREAD_COUNT * 0.5); 197 198 System.out.println("Using " + maxMemoryPerAllocThread / 1024 + "KB for each of " + ALLOC_THREAD_COUNT 199 + " allocation threads"); 200 201 while (WB.g1NumFreeRegions() > freeRegionLeft) { 202 try { 203 humongousAllocations.add(new byte[HUMONGOUS_SIZES[RND.nextInt(HUMONGOUS_SIZES.length)]]); 204 } catch (OutOfMemoryError oom) { 205 //We got OOM trying to fill heap with humongous objects 206 //It probably means that heap is fragmented which is strange since the test logic should avoid it 207 System.out.println("Warning: OOM while allocating humongous objects - it likely means " 208 + "that heap is fragmented"); 209 break; 210 } 211 } 212 213 System.out.println("Initial free regions " + initialFreeRegionsCount + "; Free regions left " 214 + WB.g1NumFreeRegions()); 215 216 LinkedList<Thread> threads = new LinkedList<>(); 217 218 for (int i = 0; i < ALLOC_THREAD_COUNT; i++) { 219 threads.add(new Thread(new Allocator(maxMemoryPerAllocThread))); 220 } 221 222 threads.stream().forEach(Thread::start); 223 224 while ((System.currentTimeMillis() - startTime < duration) && error == null) { 225 Thread.yield(); 226 } 227 228 shouldStop = true; 229 System.out.println("Finished test"); 230 if (error != null) { 231 throw error; 232 } 233 } 234 }