| /* |
| * Copyright (c) 2014, 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. |
| */ |
| |
| /* |
| * @test TestEagerReclaimHumongousRegionsClearMarkBits |
| * @bug 8051973 |
| * @summary Test to make sure that eager reclaim of humongous objects correctly clears |
| * mark bitmaps at reclaim. |
| * @key gc |
| * @library /testlibrary |
| */ |
| |
| import java.util.ArrayList; |
| import java.util.LinkedList; |
| import java.util.Random; |
| |
| import com.oracle.java.testlibrary.OutputAnalyzer; |
| import com.oracle.java.testlibrary.ProcessTools; |
| |
| // An object that has a few references to other instances to slow down marking. |
| class ObjectWithSomeRefs { |
| public ObjectWithSomeRefs other1; |
| public ObjectWithSomeRefs other2; |
| public ObjectWithSomeRefs other3; |
| public ObjectWithSomeRefs other4; |
| } |
| |
| class ReclaimRegionFast { |
| public static final long MAX_MILLIS_FOR_RUN = 50 * 1000; // The maximum runtime for the actual test. |
| |
| public static final int M = 1024*1024; |
| |
| public static LinkedList<Object> garbageList = new LinkedList<Object>(); |
| |
| public static void genGarbage(Object large) { |
| for (int i = 0; i < 64*1024; i++) { |
| Object[] garbage = new Object[50]; |
| garbage[0] = large; |
| garbageList.add(garbage); |
| } |
| garbageList.clear(); |
| } |
| |
| public static ArrayList<ObjectWithSomeRefs> longList = new ArrayList<ObjectWithSomeRefs>(); |
| |
| public static void main(String[] args) { |
| |
| for (int i = 0; i < 16*1024; i++) { |
| longList.add(new ObjectWithSomeRefs()); |
| } |
| |
| Random rnd = new Random(); |
| for (int i = 0; i < longList.size(); i++) { |
| int len = longList.size(); |
| longList.get(i).other1 = longList.get(rnd.nextInt(len)); |
| longList.get(i).other2 = longList.get(rnd.nextInt(len)); |
| longList.get(i).other3 = longList.get(rnd.nextInt(len)); |
| longList.get(i).other4 = longList.get(rnd.nextInt(len)); |
| } |
| |
| int[] large1 = new int[M]; |
| int[] large2 = null; |
| int[] large3 = null; |
| int[] large4 = null; |
| |
| Object ref_from_stack = large1; |
| |
| long start_millis = System.currentTimeMillis(); |
| |
| for (int i = 0; i < 20; i++) { |
| long current_millis = System.currentTimeMillis(); |
| if ((current_millis - start_millis) > MAX_MILLIS_FOR_RUN) { |
| System.out.println("Finishing test because maximum runtime exceeded"); |
| break; |
| } |
| // A set of large objects that will be reclaimed eagerly - and hopefully marked. |
| large1 = new int[M - 20]; |
| large2 = new int[M - 20]; |
| large3 = new int[M - 20]; |
| large4 = new int[M - 20]; |
| genGarbage(large1); |
| // Make sure that the compiler cannot completely remove |
| // the allocation of the large object until here. |
| System.out.println(large1 + " " + large2 + " " + large3 + " " + large4); |
| } |
| |
| // Keep the reference to the first object alive. |
| System.out.println(ref_from_stack); |
| } |
| } |
| |
| public class TestEagerReclaimHumongousRegionsClearMarkBits { |
| public static void main(String[] args) throws Exception { |
| ProcessBuilder pb = ProcessTools.createJavaProcessBuilder( |
| "-XX:+UseG1GC", |
| "-Xms128M", |
| "-Xmx128M", |
| "-Xmn2M", |
| "-XX:G1HeapRegionSize=1M", |
| "-XX:InitiatingHeapOccupancyPercent=0", // Want to have as much as possible initial marks. |
| "-XX:+PrintGC", |
| "-XX:+VerifyAfterGC", |
| "-XX:ConcGCThreads=1", // Want to make marking as slow as possible. |
| "-XX:+IgnoreUnrecognizedVMOptions", // G1VerifyBitmaps is develop only. |
| "-XX:+G1VerifyBitmaps", |
| ReclaimRegionFast.class.getName()); |
| OutputAnalyzer output = new OutputAnalyzer(pb.start()); |
| output.shouldHaveExitValue(0); |
| } |
| } |
| |