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.
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 package gc.stress;
25
26 /*
27 * @test TestReclaimStringsLeaksMemory
28 * @bug 8180048
29 * @summary Ensure that during a Full GC interned string memory is reclaimed completely.
30 * @requires vm.gc=="null" & !vm.graal.enabled & !vm.debug
31 * @key gc
32 * @library /test/lib
33 * @modules java.base/jdk.internal.misc
34 * @run main/othervm gc.stress.TestReclaimStringsLeaksMemory
35 * @run main/othervm gc.stress.TestReclaimStringsLeaksMemory -XX:+UseSerialGC
36 * @run main/othervm gc.stress.TestReclaimStringsLeaksMemory -XX:+UseParallelGC
37 * @run main/othervm gc.stress.TestReclaimStringsLeaksMemory -XX:+UseParallelGC -XX:-UseParallelOldGC
38 * @run main/othervm gc.stress.TestReclaimStringsLeaksMemory -XX:+UseConcMarkSweepGC
39 * @run main/othervm gc.stress.TestReclaimStringsLeaksMemory -XX:+UseG1GC
40 */
41
42 import java.util.Arrays;
43 import java.util.ArrayList;
44 import java.util.regex.Pattern;
45 import java.util.regex.Matcher;
46
47 import jdk.test.lib.Asserts;
48 import jdk.test.lib.process.OutputAnalyzer;
49 import jdk.test.lib.process.ProcessTools;
50
51 public class TestReclaimStringsLeaksMemory {
52
53 // The amount of memory in kB reserved in the "Symbol" category that indicates a memory leak for
54 // this test.
55 public static final int ReservedThreshold = 70000;
56
57 public static void main(String[] args) throws Exception {
58 ArrayList<String> baseargs = new ArrayList(Arrays.asList( "-Xms256M",
59 "-Xmx256M",
60 "-Xlog:gc*",
61 "-XX:NativeMemoryTracking=summary",
62 "-XX:+UnlockDiagnosticVMOptions",
63 "-XX:+PrintNMTStatistics" ));
64 baseargs.addAll(Arrays.asList(args));
65 baseargs.add(GCTest.class.getName());
66 ProcessBuilder pb_default =
67 ProcessTools.createJavaProcessBuilder(baseargs.toArray(new String[] {}));
68 verifySymbolMemoryUsageNotTooHigh(new OutputAnalyzer(pb_default.start()));
69 }
70
71 private static void verifySymbolMemoryUsageNotTooHigh(OutputAnalyzer output) throws Exception {
72 String stdout = output.getStdout();
73 System.out.println(stdout);
74
75 Pattern p = Pattern.compile("Symbol \\(reserved=(\\d*)");
76 Matcher m = p.matcher(stdout);
77
78 if (!m.find()) {
79 throw new RuntimeException("Could not find Symbol memory usage in NMT output");
80 }
81
82 int reserved = Integer.parseInt(m.group(1));
83 Asserts.assertLT(reserved, ReservedThreshold, "Reserved memory size is " + reserved + "KB which is greater than or equal to " + ReservedThreshold + "KB indicating a memory leak");
84
85 output.shouldHaveExitValue(0);
86 }
87
88 static class GCTest {
89 public static final String BaseName = "SomeRandomBaseString";
90 public static volatile String lastString;
91
92 public static void main(String [] args) {
93 for (int iterations = 0; iterations < 20;) {
94 for (int i = 0; i < 1000000; i++) {
95 lastString = (BaseName + i).intern();
96 }
97 if (++iterations % 5 == 0) {
98 System.gc();
99 }
100 }
101 }
102 }
103 }
104