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 TestMixedOldGenCollectionUsage.java
26 * @bug 8195115
27 * @requires vm.gc.G1
28 * @summary G1 Old Gen's CollectionUsage.used is zero after mixed GC which is incorrect
29 * @run main/othervm -Xmx64m -Xms64m -verbose:gc -XX:+UseG1GC TestMixedOldGenCollectionUsage
30 */
31 import java.util.*;
32 import java.lang.management.*;
33
34 // 8195115 says that for the "G1 Old Gen" MemoryPool, CollectionUsage.used
35 // is zero for G1 after a mixed collection.
36
37 public class TestMixedOldGenCollectionUsage {
38
39 private String poolName = "G1 Old Gen";
40 private String collectorName = "G1 Young Generation";
41
42 public static void main(String [] args) {
43 TestMixedOldGenCollectionUsage t = new TestMixedOldGenCollectionUsage();
44 t.run();
45 }
46
47 public TestMixedOldGenCollectionUsage() {
48 System.out.println("Monitor G1 Old Gen pool with G1 Young Generation collector.");
49 }
50
51 public void run() {
52 // Find memory pool and collector
53 List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();
54 MemoryPoolMXBean pool = null;
55 boolean foundPool = false;
56 for (int i = 0; i < pools.size(); i++) {
57 pool = pools.get(i);
58 String name = pool.getName();
59 if (name.contains(poolName)) {
60 System.out.println("Found pool: " + name);
61 foundPool = true;
62 break;
63 }
64 }
65 if (!foundPool) {
66 throw new RuntimeException(poolName + " not found, test with -XX:+UseG1GC");
67 }
68
69 List<GarbageCollectorMXBean> collectors = ManagementFactory.getGarbageCollectorMXBeans();
70 GarbageCollectorMXBean collector = null;
71 boolean foundCollector = false;
72 for (int i = 0; i < collectors.size(); i++) {
73 collector = collectors.get(i);
74 String name = collector.getName();
75 if (name.contains(collectorName)) {
76 System.out.println("Found collector: " + name);
77 foundCollector = true;
78 break;
79 }
80 }
81 if (!foundCollector) {
82 throw new RuntimeException(collectorName + " not found, test with -XX:+UseG1GC");
83 }
84
85 // Use some memory, enough that young, but not mixed, collections
86 // have happened.
87 allocationWork(20*1024*1024, 0);
88 System.out.println("Done allocationWork for pure young collections");
89
90 // Verify no non-zero result was stored
91 long usage = pool.getCollectionUsage().getUsed();
92 System.out.println(poolName + ": usage after GC = " + usage);
93 if (usage > 0) {
94 throw new RuntimeException("Premature mixed collections(s)");
95 }
96
97 // Verify that collections were done
98 long collectionCount = collector.getCollectionCount();
99 System.out.println(collectorName + ": collection count = "
100 + collectionCount);
101 long collectionTime = collector.getCollectionTime();
102 System.out.println(collectorName + ": collection time = "
103 + collectionTime);
104 if (collectionCount <= 0) {
105 throw new RuntimeException("Collection count <= 0");
106 }
107 if (collectionTime <= 0) {
108 throw new RuntimeException("Collector has not run");
109 }
110
111 // Must run with options to ensure no stop the world full GC,
112 // but at least one GC cycle that includes a mixed collection.
113 allocationWork(20*1024*1024, 10*1024*1024);
114 System.out.println("Done allocationWork for mixed collections");
115
116 usage = pool.getCollectionUsage().getUsed();
117 System.out.println(poolName + ": usage after GC = " + usage);
118 if (usage <= 0) {
119 throw new RuntimeException(poolName + " found with zero usage");
120 }
121
122 long newCollectionCount = collector.getCollectionCount();
123 System.out.println(collectorName + ": collection count = "
124 + newCollectionCount);
125 long newCollectionTime = collector.getCollectionTime();
126 System.out.println(collectorName + ": collection time = "
127 + newCollectionTime);
128 if (newCollectionCount <= collectionCount) {
129 throw new RuntimeException("No new collection");
130 }
131 if (newCollectionTime <= collectionTime) {
132 throw new RuntimeException("Collector has not run some more");
133 }
134
135 System.out.println("Test passed.");
136 }
137
138 public void allocationWork(long persistentTarget, long target) {
139 long persistentSizeAllocated = 0;
140 long sizeAllocated = 0;
141 char[] template = new char[10240];
142 Random rand = new Random();
143 PrimitiveIterator.OfInt indexiter = rand.ints().iterator();
144 PrimitiveIterator.OfInt valueiter = rand.ints().iterator();
145
146 Set<String> persistentStrings = new HashSet<>(1000);
147 while (persistentSizeAllocated < persistentTarget) {
148 for (int i = 0; i < 100; i++) {
149 template[Math.abs(indexiter.next() % 10240)] = (char)valueiter.nextInt();
150 persistentStrings.add(new String(template));
151 }
152 persistentSizeAllocated += 100*10240*2;
153 }
154 while (sizeAllocated < target) {
155 Set<String> strings = new HashSet<>(1000);
156 for (int i = 0; i < 1000; i++) {
157 template[Math.abs(indexiter.next() % 10240)] = (char)valueiter.nextInt();
158 strings.add(new String(template));
159 }
160 sizeAllocated += 1000*10240*2;
161 }
162 }
163 }