1 /* 2 * Copyright (c) 2018, 2019, 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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.jfr.event.gc.collection; 27 28 import static java.lang.System.gc; 29 import static java.lang.Thread.sleep; 30 import static java.util.Set.of; 31 import static java.util.stream.Collectors.joining; 32 import static java.util.stream.Collectors.toList; 33 import static java.util.stream.Collectors.toSet; 34 import static java.util.stream.IntStream.range; 35 import static jdk.jfr.event.gc.collection.Provoker.provokeMixedGC; 36 import static jdk.test.lib.Asserts.assertEquals; 37 import static jdk.test.lib.Asserts.assertTrue; 38 import static jdk.test.lib.jfr.Events.fromRecording; 39 import static sun.hotspot.WhiteBox.getWhiteBox; 40 41 import java.io.IOException; 42 import java.lang.ref.WeakReference; 43 import java.math.BigDecimal; 44 import java.util.ArrayList; 45 import java.util.Collection; 46 import java.util.List; 47 import java.util.Set; 48 49 import jdk.jfr.Recording; 50 import jdk.test.lib.Asserts; 51 import jdk.test.lib.jfr.EventNames; 52 import sun.hotspot.WhiteBox; 53 54 /** 55 * @test 56 * @key jfr 57 * @requires vm.hasJFR 58 * @requires vm.gc == "G1" | vm.gc == null 59 * @library /test/lib /test/jdk 60 * @build sun.hotspot.WhiteBox 61 * @run main ClassFileInstaller sun.hotspot.WhiteBox 62 * @run main/othervm -XX:+UnlockExperimentalVMOptions -XX:+AlwaysTenure 63 * -Xms20M -Xmx20M -Xlog:gc=debug,gc+heap*=debug,gc+ergo*=debug,gc+start=debug 64 * -XX:G1MixedGCLiveThresholdPercent=100 -XX:G1HeapWastePercent=0 -XX:G1HeapRegionSize=1m 65 * -XX:+UseG1GC -XX:+UseStringDeduplication 66 * -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI 67 * jdk.jfr.event.gc.collection.TestG1ParallelPhases 68 */ 69 70 public class TestG1ParallelPhases { 71 public static List<WeakReference<byte[]>> weakRefs; 72 73 public static void main(String[] args) throws IOException { 74 Recording recording = new Recording(); 75 recording.enable(EventNames.GCPhaseParallel); 76 recording.start(); 77 78 // create more weak garbage than can fit in this heap (-Xmx20m), will force collection of weak references 79 weakRefs = range(1, 30) 80 .mapToObj(n -> new WeakReference<>(new byte[1_000_000])) 81 .collect(toList()); // force evaluation of lazy stream (all weak refs must be created) 82 83 final var MEG = 1024 * 1024; 84 provokeMixedGC(1 * MEG); 85 recording.stop(); 86 87 Set<String> usedPhases = fromRecording(recording).stream() 88 .map(e -> e.getValue("name").toString()) 89 .collect(toSet()); 90 91 Set<String> allPhases = of( 92 "ExtRootScan", 93 "ThreadRoots", 94 "UniverseRoots", 95 "JNIRoots", 96 "ObjectSynchronizerRoots", 97 "ManagementRoots", 98 "SystemDictionaryRoots", 99 "CLDGRoots", 100 "JVMTIRoots", 101 "CMRefRoots", 102 "MergeER", 103 "MergeHCC", 104 "MergeRS", 105 "MergeLB", 106 "ScanHR", 107 "CodeRoots", 108 "ObjCopy", 109 "Termination", 110 "StringDedupQueueFixup", 111 "StringDedupTableFixup", 112 "RedirtyCards", 113 "NonYoungFreeCSet", 114 "YoungFreeCSet" 115 ); 116 117 // Some GC phases may or may not occur depending on environment. Filter them out 118 // since we can not reliably guarantee that they occur (or not). 119 Set<String> optPhases = of( 120 "OptScanHR", 121 "OptMergeRS", 122 "OptCodeRoots", 123 "OptObjCopy" 124 ); 125 usedPhases.removeAll(optPhases); 126 127 assertTrue(usedPhases.equals(allPhases), "Compare events expected and received" 128 + ", Not found phases: " + allPhases.stream().filter(p -> !usedPhases.contains(p)).collect(joining(", ")) 129 + ", Not expected phases: " + usedPhases.stream().filter(p -> !allPhases.contains(p)).collect(joining(", "))); 130 } 131 } 132 133 /** 134 * Utility class to guarantee a mixed GC. The class allocates several arrays and 135 * promotes them to the oldgen. After that it tries to provoke mixed GC by 136 * allocating new objects. 137 */ 138 class Provoker { 139 private static void allocateOldObjects( 140 List<byte[]> liveOldObjects, 141 int g1HeapRegionSize, 142 int arraySize) { 143 144 var toUnreachable = new ArrayList<byte[]>(); 145 146 // Allocates buffer and promotes it to the old gen. Mix live and dead old objects. 147 // allocate about two regions of old memory. At least one full old region will guarantee 148 // mixed collection in the future 149 range(0, g1HeapRegionSize/arraySize).forEach(n -> { 150 liveOldObjects.add(new byte[arraySize]); 151 toUnreachable.add(new byte[arraySize]); 152 }); 153 154 // Do one young collection, AlwaysTenure will force promotion. 155 getWhiteBox().youngGC(); 156 157 // Check it is promoted & keep alive 158 Asserts.assertTrue(getWhiteBox().isObjectInOldGen(liveOldObjects), "List of the objects is suppose to be in OldGen"); 159 Asserts.assertTrue(getWhiteBox().isObjectInOldGen(toUnreachable), "List of the objects is suppose to be in OldGen"); 160 } 161 162 private static void waitTillCMCFinished(int sleepTime) { 163 while (getWhiteBox().g1InConcurrentMark()) { 164 try {sleep(sleepTime);} catch (Exception e) {} 165 } 166 } 167 168 /** 169 * The necessary condition for guaranteed mixed GC is running in VM with the following flags: 170 * -XX:+UnlockExperimentalVMOptions -XX:+AlwaysTenure -Xms{HEAP_SIZE}M 171 * -Xmx{HEAP_SIZE}M -XX:G1MixedGCLiveThresholdPercent=100 -XX:G1HeapWastePercent=0 172 * -XX:G1HeapRegionSize={REGION_SIZE}m 173 * 174 * @param g1HeapRegionSize The size of your regions in bytes 175 */ 176 public static void provokeMixedGC(int g1HeapRegionSize) { 177 final var arraySize = 20_000; 178 var liveOldObjects = new ArrayList<byte[]>(); 179 allocateOldObjects(liveOldObjects, g1HeapRegionSize, arraySize); 180 waitTillCMCFinished(10); 181 getWhiteBox().g1StartConcMarkCycle(); 182 waitTillCMCFinished(10); 183 getWhiteBox().youngGC(); 184 getWhiteBox().youngGC(); 185 186 // check that liveOldObjects still alive 187 assertTrue(getWhiteBox().isObjectInOldGen(liveOldObjects), "List of the objects is suppose to be in OldGen"); 188 } 189 }