1 /* 2 * Copyright (c) 2017, 2018, 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 /* 26 * @test 27 * @key stress gc 28 * 29 * @summary converted from VM Testbase gc/gctests/LargeObjects/large004. 30 * VM Testbase keywords: [gc, stress, stressopt, nonconcurrent] 31 * VM Testbase readme: 32 * DESCRIPTION 33 * The test checks that Garbage Collector correctly does not throw any 34 * unexpected exceptions/errors while allocating large objects (classes 35 * that have more than 65535 fields and classes that have less than 65535 36 * fields). 65535 of fields is a limitation for JVM (see JVM specification 37 * Second edition 4.10). 38 * Since it is impossible to create one class with about 65535 of fields 39 * (javac cannot compile it), a child class extends a parent class, so the 40 * fields are devided into two subsets. However, the child class still has 41 * about 65535 of fields. 42 * The test starts a number of threads. This number is either set in *.cfg 43 * file or is calculated by the test itself based on the machine (see 44 * nsk.share.gc.Algorithms.getThreadsCount() method). As soon as all threads 45 * are started, each thread begins its checking. 46 * There are 13 classes to be loaded by each thread. These classes are 47 * generated by nsk.share.gc.Generator (see its javadoc for more details). 48 * Each class has a huge number of fields, but this number is less than the JVM 49 * limitation. 50 * The test loads the classes with nsk.share.gc.GCClassUnloader class that 51 * extends nsk.share.ClassUnloader and has a bit different algorith of eating 52 * heap. As soon as a class is loaded, the test creates an instance of 53 * it - allocates an object of that type. Then it drops references to the 54 * class and to the instance and tries to unload the class. The test does not 55 * expect any exceptions to be thrown. 56 * Additionaly to original tests this test create object with large count of 57 * field which contains also a reference to other such object wich also 58 * contains same reference and so on. The deep of such aggregation is controlled 59 * by the test. These references are verified after GC. 60 * 61 * @library /vmTestbase 62 * /test/lib 63 * @run driver jdk.test.lib.FileInstaller . . 64 * 65 * @comment generate and compile nsk.share.gc.newclass.* classes 66 * @run driver nsk.share.gc.GenClassesBuilder 67 * 68 * @run main/othervm 69 * -XX:-UseGCOverheadLimit 70 * gc.gctests.LargeObjects.large001.large001 71 * -largeClassesPath classes 72 * -isOverLimitFields true 73 * -aggregationDepth 1 74 * -t 1 75 */ 76