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 TestPeriodicCollection
26 * @requires vm.gc.G1
27 * @summary Verify that heap shrinks when the application is idle.
28 * @library /test/lib /
29 * @modules java.base/jdk.internal.misc
30 * @modules java.management/sun.management
31 * @build sun.hotspot.WhiteBox
32 * @run driver ClassFileInstaller sun.hotspot.WhiteBox
33 * sun.hotspot.WhiteBox$WhiteBoxPermission
34 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. -Xms32M -Xmx128M -XX:MinHeapFreeRatio=5 -XX:MaxHeapFreeRatio=25 -XX:+UseG1GC -XX:G1PeriodicGCInterval=3000 -XX:+G1PeriodicGCInvokesConcurrent -Xlog:gc,gc+periodic=debug,gc+ergo+heap=debug TestPeriodicCollection
35 * @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -Xbootclasspath/a:. -Xms32M -Xmx128M -XX:MinHeapFreeRatio=5 -XX:MaxHeapFreeRatio=25 -XX:+UseG1GC -XX:G1PeriodicGCInterval=3000 -XX:-G1PeriodicGCInvokesConcurrent -Xlog:gc,gc+periodic=debug,gc+ergo+heap=debug TestPeriodicCollection
36 */
37
38 import com.sun.management.HotSpotDiagnosticMXBean;
39
40 import gc.testlibrary.Helpers;
41
42 import java.lang.management.ManagementFactory;
43 import java.lang.management.MemoryUsage;
44 import java.util.ArrayList;
45 import java.util.List;
46 import java.text.NumberFormat;
47 import static jdk.test.lib.Asserts.*;
48
49 import sun.hotspot.WhiteBox;
50
51 public class TestPeriodicCollection {
52
53 public static final String MIN_FREE_RATIO_FLAG_NAME = "MinHeapFreeRatio";
54 public static final String MAX_FREE_RATIO_FLAG_NAME = "MaxHeapFreeRatio";
55
56 private static final List<List<byte[]>> garbage = new ArrayList();
57
58 private static final long TOTAL_MEMORY = Runtime.getRuntime().totalMemory();
59 private static final long MAX_MEMORY = Runtime.getRuntime().maxMemory();
60 private static final int IDLE_TIME = 10 * 1000;
61
62 private static final int ARR_SIZE = 64 * 1024; // 64k
63 private static final int LISTS_COUNT = 10;
64 private static final int ARR_COUNT = (int) ((TOTAL_MEMORY / ARR_SIZE) / LISTS_COUNT);
65
66 public static void main(String[] args) {
67 if (ARR_COUNT == 0) {
68 System.out.println("Skipped. Heap is too small");
69 return;
70 }
71
72 if (TOTAL_MEMORY + ARR_SIZE * ARR_COUNT > MAX_MEMORY) {
73 System.out.println("Skipped. Initial heap size is too close to max heap size.");
74 return;
75 }
76
77 new TestPeriodicCollection().test();
78 }
79
80 private final void test() {
81 WhiteBox.getWhiteBox().fullGC();
82
83 MemoryUsagePrinter.printMemoryUsage("init");
84
85 allocate();
86 MemoryUsagePrinter.printMemoryUsage("allocated");
87 MemoryUsage muFull = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage();
88
89 garbage.clear();
90 try {
91 Thread.sleep(IDLE_TIME);
92 } catch (InterruptedException ie) {
93 System.err.println("Skipped. Failed to wait for idle collection");
94 }
95 MemoryUsagePrinter.printMemoryUsage("free");
96 MemoryUsage muFree = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage();
97
98 assertLessThan(muFree.getCommitted(), muFull.getCommitted(), String.format(
99 "committed free heap size is not less than committed full heap size, heap hasn't been shrunk?%n"
100 + "%s = %s%n%s = %s",
101 MIN_FREE_RATIO_FLAG_NAME,
102 ManagementFactory.getPlatformMXBean(HotSpotDiagnosticMXBean.class)
103 .getVMOption(MIN_FREE_RATIO_FLAG_NAME).getValue(),
104 MAX_FREE_RATIO_FLAG_NAME,
105 ManagementFactory.getPlatformMXBean(HotSpotDiagnosticMXBean.class)
106 .getVMOption(MAX_FREE_RATIO_FLAG_NAME).getValue()
107 ));
108 }
109
110 private void allocate() {
111
112 for (int i = 0; i < LISTS_COUNT; i++) {
113 List<byte[]> stuff = new ArrayList();
114 allocateList(stuff, ARR_COUNT, ARR_SIZE);
115 MemoryUsagePrinter.printMemoryUsage("allocate #" + (i+1));
116 garbage.add(stuff);
117 }
118 }
119
120 private static void allocateList(List garbage, int count, int size) {
121 for (int i = 0; i < count; i++) {
122 garbage.add(new byte[size]);
123 }
124 }
125 }
126
127 /**
128 * Prints memory usage to standard output
129 */
130 class MemoryUsagePrinter {
131
132 public static final NumberFormat NF = Helpers.numberFormatter();
133
134 public static void printMemoryUsage(String label) {
135 MemoryUsage memusage = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage();
136 float freeratio = 1f - (float) memusage.getUsed() / memusage.getCommitted();
137 System.out.format("[%-24s] init: %-7s, used: %-7s, comm: %-7s, freeRatio ~= %.1f%%%n",
138 label,
139 NF.format(memusage.getInit()),
140 NF.format(memusage.getUsed()),
141 NF.format(memusage.getCommitted()),
142 freeratio * 100
143 );
144 }
145 }