| /* |
| * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package gc.g1.humongousObjects; |
| |
| import gc.testlibrary.Helpers; |
| import jdk.test.lib.Asserts; |
| import sun.hotspot.WhiteBox; |
| |
| import java.lang.ref.Reference; |
| import java.lang.ref.ReferenceQueue; |
| import java.lang.ref.SoftReference; |
| import java.lang.ref.WeakReference; |
| |
| /** |
| * @test TestObjectCollected |
| * @summary checks that after different type of GCs weak/soft references to humongous object behave correspondingly to |
| * actual object behavior |
| * @requires vm.gc.G1 |
| * @library /test/lib / |
| * @modules java.base/jdk.internal.misc |
| * @modules java.management |
| * @build sun.hotspot.WhiteBox |
| * @run driver ClassFileInstaller sun.hotspot.WhiteBox |
| * sun.hotspot.WhiteBox$WhiteBoxPermission |
| * |
| * @run main/othervm -XX:+UseG1GC -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions |
| * -XX:+WhiteBoxAPI -Xbootclasspath/a:. -Xms200m -Xmx200m -Xlog:gc |
| * -XX:InitiatingHeapOccupancyPercent=100 -XX:G1HeapRegionSize=1M -Xlog:gc=info:file=TestObjectCollected.gc.log |
| * gc.g1.humongousObjects.TestObjectCollected |
| */ |
| |
| |
| /** |
| * Test checks that after different type of GCs weak/soft references to humongous object behave correspondingly to |
| * actual object behavior. |
| * So if object was collected, reference.get() should return null and vice versa |
| * Since we check humongous objects after such an object is collected the region where it was allocated becomes free |
| * or/and change type to non-humongous. Two WhiteBox method were used - first returns if a region containing certain |
| * address is free and second - if a region containing certain address is humongous |
| */ |
| |
| public class TestObjectCollected { |
| /** |
| * Provides methods to initiate GC of requested type |
| */ |
| private enum GC { |
| YOUNG_CG { |
| @Override |
| public void provoke() { |
| WHITE_BOX.youngGC(); |
| } |
| }, |
| FULL_GC { |
| @Override |
| public void provoke() { |
| System.gc(); |
| } |
| }, |
| CMC { |
| @Override |
| public void provoke() { |
| Helpers.waitTillCMCFinished(WHITE_BOX, 0); |
| WHITE_BOX.g1StartConcMarkCycle(); |
| Helpers.waitTillCMCFinished(WHITE_BOX, 0); |
| } |
| }, |
| FULL_GC_MEMORY_PRESSURE { |
| @Override |
| public void provoke() { |
| WHITE_BOX.fullGC(); |
| } |
| }; |
| private static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox(); |
| |
| public abstract void provoke(); |
| } |
| |
| /** |
| * Factory for weak and soft references. |
| * Allocates byte array of ALLOCATION_SIZE and returns weak/soft reference on it. |
| */ |
| private enum REF_FACTORY { |
| WEAK { |
| @Override |
| public Reference<byte[]> create() { |
| return new WeakReference<>(new byte[ALLOCATION_SIZE], referenceQueqe); |
| } |
| }, |
| SOFT { |
| @Override |
| public Reference<byte[]> create() { |
| return new SoftReference<>(new byte[ALLOCATION_SIZE], referenceQueqe); |
| } |
| }; |
| |
| private static final ReferenceQueue<byte[]> referenceQueqe = new ReferenceQueue<>(); |
| private static final int ALLOCATION_SIZE = WhiteBox.getWhiteBox().g1RegionSize() * 2 / 3; |
| |
| /** |
| * Factory method |
| * |
| * @return weak/soft reference on byte array of ALLOCATION_SIZE |
| */ |
| public abstract Reference<byte[]> create(); |
| } |
| |
| |
| private static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox(); |
| |
| /** |
| * Does actual testing: |
| * Gets a reference |
| * Gets address of referenced object using WB method |
| * Calls gc of provided type |
| * Checks that object was/was not deleted using WB methods. |
| */ |
| public static void doTesting(GC gc, REF_FACTORY ref) { |
| |
| System.out.println(String.format("Testing %s reference behavior after %s", ref.name(), gc.name())); |
| |
| Reference reference = ref.create(); |
| Asserts.assertNotNull(reference, "Test Bug: failed to allocate reference"); |
| long adr = WHITE_BOX.getObjectAddress(reference.get()); |
| |
| //Sanity checks |
| boolean isRefNulled = (reference.get() == null); |
| boolean isRegionHumongous = WHITE_BOX.g1BelongsToHumongousRegion(adr); |
| boolean isRegionFree = WHITE_BOX.g1BelongsToFreeRegion(adr); |
| |
| |
| Asserts.assertEquals(isRefNulled, false, |
| "We just allocated an object but reference.get() already returned null"); |
| |
| Asserts.assertEquals(isRegionFree, false, |
| "We just allocated an object but WB returns that allocation region is still considered free"); |
| |
| Asserts.assertEquals(isRegionHumongous, true, |
| "We just allocated a humongous object but WB returns that allocation region is not humongous"); |
| |
| gc.provoke(); |
| |
| isRefNulled = (reference.get() == null); |
| isRegionHumongous = WHITE_BOX.g1BelongsToHumongousRegion(adr); |
| isRegionFree = WHITE_BOX.g1BelongsToFreeRegion(adr); |
| |
| boolean isObjCollected = isRegionFree || !isRegionHumongous; |
| |
| Asserts.assertEquals(isRefNulled, isObjCollected, |
| String.format("There is an inconsistensy between reference and white box " |
| + "method behavior - one considers object referenced with " |
| + "%s type collected and another doesn't!\n" |
| + "\treference.get() returned %snull\n" |
| + "\tWhiteBox methods returned that object was%s collected", |
| reference.getClass().getSimpleName(), |
| (isRefNulled ? "" : "not "), |
| (isObjCollected ? "" : " not"))); |
| |
| System.out.println("Passed"); |
| } |
| |
| /** |
| * Entry point |
| * |
| * @param args not used |
| */ |
| public static void main(String[] args) { |
| // Full gc - System.gc() |
| TestObjectCollected.doTesting(GC.FULL_GC, REF_FACTORY.WEAK); |
| TestObjectCollected.doTesting(GC.FULL_GC, REF_FACTORY.SOFT); |
| |
| // Full gc with memory pressure - WB.fullGC() emulates that no memory left |
| TestObjectCollected.doTesting(GC.FULL_GC_MEMORY_PRESSURE, REF_FACTORY.WEAK); |
| TestObjectCollected.doTesting(GC.FULL_GC_MEMORY_PRESSURE, REF_FACTORY.SOFT); |
| |
| // Young gc |
| TestObjectCollected.doTesting(GC.YOUNG_CG, REF_FACTORY.WEAK); |
| TestObjectCollected.doTesting(GC.YOUNG_CG, REF_FACTORY.SOFT); |
| |
| // Concurrent mark cycle |
| TestObjectCollected.doTesting(GC.CMC, REF_FACTORY.WEAK); |
| TestObjectCollected.doTesting(GC.CMC, REF_FACTORY.SOFT); |
| } |
| } |