1 /* 2 * Copyright (c) 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 * @test TestReclaimStringsLeaksMemory 26 * @bug 8180048 27 * @summary Ensure that during a Full GC interned string memory is reclaimed completely. 28 * @requires vm.gc=="null" 29 * @requires !vm.debug 30 * @key gc 31 * @library /test/lib 32 * @modules java.base/jdk.internal.misc 33 * @run main/othervm TestReclaimStringsLeaksMemory 34 * @run main/othervm TestReclaimStringsLeaksMemory -XX:+UseSerialGC 35 * @run main/othervm TestReclaimStringsLeaksMemory -XX:+UseParallelGC 36 * @run main/othervm TestReclaimStringsLeaksMemory -XX:+UseParallelGC -XX:-UseParallelOldGC 37 * @run main/othervm TestReclaimStringsLeaksMemory -XX:+UseConcMarkSweepGC 38 * @run main/othervm TestReclaimStringsLeaksMemory -XX:+UseG1GC 39 */ 40 41 import java.util.Arrays; 42 import java.util.ArrayList; 43 import java.util.regex.Pattern; 44 import java.util.regex.Matcher; 45 46 import jdk.test.lib.Asserts; 47 import jdk.test.lib.process.OutputAnalyzer; 48 import jdk.test.lib.process.ProcessTools; 49 50 public class TestReclaimStringsLeaksMemory { 51 52 // The amount of memory in kB reserved in the "Symbol" category that indicates a memory leak for 53 // this test. 54 public static final int ReservedThreshold = 70000; 55 56 public static void main(String[] args) throws Exception { 57 ArrayList<String> baseargs = new ArrayList(Arrays.asList( "-Xms256M", 58 "-Xmx256M", 59 "-Xlog:gc*", 60 "-XX:NativeMemoryTracking=summary", 61 "-XX:+UnlockDiagnosticVMOptions", 62 "-XX:+PrintNMTStatistics" )); 63 baseargs.addAll(Arrays.asList(args)); 64 baseargs.add(GCTest.class.getName()); 65 ProcessBuilder pb_default = 66 ProcessTools.createJavaProcessBuilder(baseargs.toArray(new String[] {})); 67 verifySymbolMemoryUsageNotTooHigh(new OutputAnalyzer(pb_default.start())); 68 } 69 70 private static void verifySymbolMemoryUsageNotTooHigh(OutputAnalyzer output) throws Exception { 71 String stdout = output.getStdout(); 72 System.out.println(stdout); 73 74 Pattern p = Pattern.compile("Symbol \\(reserved=(\\d*)"); 75 Matcher m = p.matcher(stdout); 76 77 if (!m.find()) { 78 throw new RuntimeException("Could not find Symbol memory usage in NMT output"); 79 } 80 81 int reserved = Integer.parseInt(m.group(1)); 82 Asserts.assertLT(reserved, ReservedThreshold, "Reserved memory size is " + reserved + "KB which is greater than or equal to " + ReservedThreshold + "KB indicating a memory leak"); 83 84 output.shouldHaveExitValue(0); 85 } 86 87 static class GCTest { 88 public static final String BaseName = "SomeRandomBaseString"; 89 public static volatile String lastString; 90 91 public static void main(String [] args) { 92 for (int iterations = 0; iterations < 20;) { 93 for (int i = 0; i < 1000000; i++) { 94 lastString = (BaseName + i).intern(); 95 } 96 if (++iterations % 5 == 0) { 97 System.gc(); 98 } 99 } 100 } 101 } 102 } 103