1 /*
   2  * Copyright (c) 2014, 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 import jdk.test.lib.Asserts;
  25 import jdk.test.lib.OutputAnalyzer;
  26 import jdk.test.lib.Platform;
  27 import jdk.test.lib.ProcessTools;
  28 import jdk.test.lib.Utils;
  29 import java.io.IOException;
  30 import java.lang.management.ManagementFactory;
  31 import java.lang.management.MemoryUsage;
  32 import java.text.DecimalFormat;
  33 import java.text.DecimalFormatSymbols;
  34 import java.util.ArrayList;
  35 import java.util.Arrays;
  36 import java.util.Collections;
  37 import java.util.LinkedList;
  38 import java.util.List;
  39 import jdk.internal.misc.Unsafe; // for ADDRESS_SIZE
  40 import sun.hotspot.WhiteBox;
  41 
  42 public class TestShrinkAuxiliaryData {
  43 
  44     private static final int REGION_SIZE = 1024 * 1024;
  45 
  46     private final static String[] initialOpts = new String[]{
  47         "-XX:NewSize=16m",
  48         "-XX:MinHeapFreeRatio=10",
  49         "-XX:MaxHeapFreeRatio=11",
  50         "-XX:+UseG1GC",
  51         "-XX:G1HeapRegionSize=" + REGION_SIZE,
  52         "-XX:-ExplicitGCInvokesConcurrent",
  53         "-Xlog:gc=debug",
  54         "-XX:+UnlockDiagnosticVMOptions",
  55         "-XX:+WhiteBoxAPI",
  56         "-XaddExports:java.base/jdk.internal.misc=ALL-UNNAMED",
  57         "-Xbootclasspath/a:.",
  58     };
  59 
  60     private final int hotCardTableSize;
  61 
  62     protected TestShrinkAuxiliaryData(int hotCardTableSize) {
  63         this.hotCardTableSize = hotCardTableSize;
  64     }
  65 
  66     protected void test() throws Exception {
  67         ArrayList<String> vmOpts = new ArrayList();
  68         Collections.addAll(vmOpts, initialOpts);
  69 
  70         int maxCacheSize = Math.max(0, Math.min(31, getMaxCacheSize()));
  71         if (maxCacheSize < hotCardTableSize) {
  72             System.out.format("Skiping test for %d cache size due max cache size %d",
  73                     hotCardTableSize, maxCacheSize
  74             );
  75             return;
  76         }
  77 
  78         printTestInfo(maxCacheSize);
  79 
  80         vmOpts.add("-XX:G1ConcRSLogCacheSize=" + hotCardTableSize);
  81 
  82         // for 32 bits ObjectAlignmentInBytes is not a option
  83         if (Platform.is32bit()) {
  84             ArrayList<String> vmOptsWithoutAlign = new ArrayList(vmOpts);
  85             vmOptsWithoutAlign.add(ShrinkAuxiliaryDataTest.class.getName());
  86             performTest(vmOptsWithoutAlign);
  87             return;
  88         }
  89 
  90         for (int alignment = 3; alignment <= 8; alignment++) {
  91             ArrayList<String> vmOptsWithAlign = new ArrayList(vmOpts);
  92             vmOptsWithAlign.add("-XX:ObjectAlignmentInBytes="
  93                     + (int) Math.pow(2, alignment));
  94             vmOptsWithAlign.add(ShrinkAuxiliaryDataTest.class.getName());
  95 
  96             performTest(vmOptsWithAlign);
  97         }
  98     }
  99 
 100     private void performTest(List<String> opts) throws Exception {
 101         ProcessBuilder pb
 102                 = ProcessTools.createJavaProcessBuilder(true,
 103                         opts.toArray(new String[opts.size()])
 104                 );
 105 
 106         OutputAnalyzer output = new OutputAnalyzer(pb.start());
 107         System.out.println(output.getStdout());
 108         System.err.println(output.getStderr());
 109         output.shouldHaveExitValue(0);
 110     }
 111 
 112     private void printTestInfo(int maxCacheSize) {
 113 
 114         DecimalFormat grouped = new DecimalFormat("000,000");
 115         DecimalFormatSymbols formatSymbols = grouped.getDecimalFormatSymbols();
 116         formatSymbols.setGroupingSeparator(' ');
 117         grouped.setDecimalFormatSymbols(formatSymbols);
 118 
 119         System.out.format(
 120                 "Test will use %s bytes of memory of %s available%n"
 121                 + "Available memory is %s with %d bytes pointer size - can save %s pointers%n"
 122                 + "Max cache size: 2^%d = %s elements%n",
 123                 grouped.format(ShrinkAuxiliaryDataTest.getMemoryUsedByTest()),
 124                 grouped.format(Runtime.getRuntime().maxMemory()),
 125                 grouped.format(Runtime.getRuntime().maxMemory()
 126                         - ShrinkAuxiliaryDataTest.getMemoryUsedByTest()),
 127                 Unsafe.ADDRESS_SIZE,
 128                 grouped.format((Runtime.getRuntime().freeMemory()
 129                         - ShrinkAuxiliaryDataTest.getMemoryUsedByTest())
 130                         / Unsafe.ADDRESS_SIZE),
 131                 maxCacheSize,
 132                 grouped.format((int) Math.pow(2, maxCacheSize))
 133         );
 134     }
 135 
 136     /**
 137      * Detects maximum possible size of G1ConcRSLogCacheSize available for
 138      * current process based on maximum available process memory size
 139      *
 140      * @return power of two
 141      */
 142     private static int getMaxCacheSize() {
 143         long availableMemory = Runtime.getRuntime().freeMemory()
 144                 - ShrinkAuxiliaryDataTest.getMemoryUsedByTest() - 1l;
 145         if (availableMemory <= 0) {
 146             return 0;
 147         }
 148 
 149         long availablePointersCount = availableMemory / Unsafe.ADDRESS_SIZE;
 150         return (63 - (int) Long.numberOfLeadingZeros(availablePointersCount));
 151     }
 152 
 153     static class ShrinkAuxiliaryDataTest {
 154 
 155         public static void main(String[] args) throws IOException {
 156 
 157             ShrinkAuxiliaryDataTest testCase = new ShrinkAuxiliaryDataTest();
 158 
 159             if (!testCase.checkEnvApplicability()) {
 160                 return;
 161             }
 162 
 163             testCase.test();
 164         }
 165 
 166         /**
 167          * Checks is this environment suitable to run this test
 168          * - memory is enough to decommit (page size is not big)
 169          * - RSet cache size is not too big
 170          *
 171          * @return true if test could run, false if test should be skipped
 172          */
 173         protected boolean checkEnvApplicability() {
 174 
 175             int pageSize = WhiteBox.getWhiteBox().getVMPageSize();
 176             System.out.println( "Page size = " + pageSize
 177                     + " region size = " + REGION_SIZE
 178                     + " aux data ~= " + (REGION_SIZE * 3 / 100));
 179             // If auxdata size will be less than page size it wouldn't decommit.
 180             // Auxiliary data size is about ~3.6% of heap size.
 181             if (pageSize >= REGION_SIZE * 3 / 100) {
 182                 System.out.format("Skipping test for too large page size = %d",
 183                        pageSize
 184                 );
 185                 return false;
 186             }
 187 
 188             if (REGION_SIZE * REGIONS_TO_ALLOCATE > Runtime.getRuntime().maxMemory()) {
 189                 System.out.format("Skipping test for too low available memory. "
 190                         + "Need %d, available %d",
 191                         REGION_SIZE * REGIONS_TO_ALLOCATE,
 192                         Runtime.getRuntime().maxMemory()
 193                 );
 194                 return false;
 195             }
 196 
 197             return true;
 198         }
 199 
 200         class GarbageObject {
 201 
 202             private final List<byte[]> payload = new ArrayList();
 203             private final List<GarbageObject> ref = new LinkedList();
 204 
 205             public GarbageObject(int size) {
 206                 payload.add(new byte[size]);
 207             }
 208 
 209             public void addRef(GarbageObject g) {
 210                 ref.add(g);
 211             }
 212 
 213             public void mutate() {
 214                 if (!payload.isEmpty() && payload.get(0).length > 0) {
 215                     payload.get(0)[0] = (byte) (Math.random() * Byte.MAX_VALUE);
 216                 }
 217             }
 218         }
 219 
 220         private final List<GarbageObject> garbage = new ArrayList();
 221 
 222         public void test() throws IOException {
 223 
 224             MemoryUsage muFull, muFree, muAuxDataFull, muAuxDataFree;
 225             float auxFull, auxFree;
 226 
 227             allocate();
 228             link();
 229             mutate();
 230 
 231             muFull = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage();
 232             long numUsedRegions = WhiteBox.getWhiteBox().g1NumMaxRegions()
 233                     - WhiteBox.getWhiteBox().g1NumFreeRegions();
 234             muAuxDataFull = WhiteBox.getWhiteBox().g1AuxiliaryMemoryUsage();
 235             auxFull = (float)muAuxDataFull.getUsed() / numUsedRegions;
 236 
 237             System.out.format("Full aux data  ratio= %f, regions max= %d, used= %d\n",
 238                     auxFull, WhiteBox.getWhiteBox().g1NumMaxRegions(), numUsedRegions
 239             );
 240 
 241             deallocate();
 242             System.gc();
 243 
 244             muFree = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage();
 245             muAuxDataFree = WhiteBox.getWhiteBox().g1AuxiliaryMemoryUsage();
 246 
 247             numUsedRegions = WhiteBox.getWhiteBox().g1NumMaxRegions()
 248                     - WhiteBox.getWhiteBox().g1NumFreeRegions();
 249             auxFree = (float)muAuxDataFree.getUsed() / numUsedRegions;
 250 
 251             System.out.format("Free aux data ratio= %f, regions max= %d, used= %d\n",
 252                     auxFree, WhiteBox.getWhiteBox().g1NumMaxRegions(), numUsedRegions
 253             );
 254 
 255             Asserts.assertLessThanOrEqual(muFree.getCommitted(), muFull.getCommitted(),
 256                     String.format("heap decommit failed - full > free: %d > %d",
 257                             muFree.getCommitted(), muFull.getCommitted()
 258                     )
 259             );
 260 
 261             System.out.format("State               used   committed\n");
 262             System.out.format("Full aux data: %10d %10d\n", muAuxDataFull.getUsed(), muAuxDataFull.getCommitted());
 263             System.out.format("Free aux data: %10d %10d\n", muAuxDataFree.getUsed(), muAuxDataFree.getCommitted());
 264 
 265             // if decommited check that aux data has same ratio
 266             if (muFree.getCommitted() < muFull.getCommitted()) {
 267                 Asserts.assertLessThanOrEqual(auxFree, auxFull,
 268                         String.format("auxiliary data decommit failed - full > free: %f > %f",
 269                                 auxFree, auxFull
 270                         )
 271                 );
 272             }
 273         }
 274 
 275         private void allocate() {
 276             for (int r = 0; r < REGIONS_TO_ALLOCATE; r++) {
 277                 for (int i = 0; i < NUM_OBJECTS_PER_REGION; i++) {
 278                     GarbageObject g = new GarbageObject(REGION_SIZE
 279                             / NUM_OBJECTS_PER_REGION);
 280                     garbage.add(g);
 281                 }
 282             }
 283         }
 284 
 285         /**
 286          * Iterate through all allocated objects, and link to objects in another
 287          * regions
 288          */
 289         private void link() {
 290             for (int ig = 0; ig < garbage.size(); ig++) {
 291                 int regionNumber = ig / NUM_OBJECTS_PER_REGION;
 292 
 293                 for (int i = 0; i < NUM_LINKS; i++) {
 294                     int regionToLink;
 295                     do {
 296                         regionToLink = (int) (Math.random() * REGIONS_TO_ALLOCATE);
 297                     } while (regionToLink == regionNumber);
 298 
 299                     // get random garbage object from random region
 300                     garbage.get(ig).addRef(garbage.get(regionToLink
 301                             * NUM_OBJECTS_PER_REGION + (int) (Math.random()
 302                             * NUM_OBJECTS_PER_REGION)));
 303                 }
 304             }
 305         }
 306 
 307         private void mutate() {
 308             for (int ig = 0; ig < garbage.size(); ig++) {
 309                 garbage.get(ig).mutate();
 310             }
 311         }
 312 
 313         private void deallocate() {
 314             garbage.clear();
 315             System.gc();
 316         }
 317 
 318         static long getMemoryUsedByTest() {
 319             return REGIONS_TO_ALLOCATE * REGION_SIZE;
 320         }
 321 
 322         private static final int REGIONS_TO_ALLOCATE = 100;
 323         private static final int NUM_OBJECTS_PER_REGION = 10;
 324         private static final int NUM_LINKS = 20; // how many links create for each object
 325     }
 326 }