1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
/*
* Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
import java.io.IOException;
import java.io.UncheckedIOException;
import java.lang.management.BufferPoolMXBean;
import java.lang.management.ManagementFactory;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import static java.nio.file.StandardOpenOption.CREATE;
import static java.nio.file.StandardOpenOption.TRUNCATE_EXISTING;
import static java.nio.file.StandardOpenOption.WRITE;
/*
* @test
* @bug 8202788
* @summary Test reclamation of thread-local temporary direct byte buffers at thread exit
* @modules java.management
* @run main/othervm TempDirectBuffersReclamation
*/
public class TempDirectBuffersReclamation {
public static void main(String[] args) throws IOException {
BufferPoolMXBean dbPool = ManagementFactory
.getPlatformMXBeans(BufferPoolMXBean.class)
.stream()
.filter(bp -> bp.getName().equals("direct"))
.findFirst()
.orElseThrow(() -> new RuntimeException("Can't obtain direct BufferPoolMXBean"));
long count0 = dbPool.getCount();
long memoryUsed0 = dbPool.getMemoryUsed();
Thread thread = new Thread(TempDirectBuffersReclamation::doFileChannelWrite);
thread.start();
try {
thread.join();
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
long count1 = dbPool.getCount();
long memoryUsed1 = dbPool.getMemoryUsed();
if (count0 != count1 || memoryUsed0 != memoryUsed1) {
throw new AssertionError(
"Direct BufferPool not same before thread activity and after thread exit.\n" +
"Before: # of buffers: " + count0 + ", memory used: " + memoryUsed0 + "\n" +
" After: # of buffers: " + count1 + ", memory used: " + memoryUsed1 + "\n"
);
}
}
static void doFileChannelWrite() {
try {
Path file = Files.createTempFile("test", ".tmp");
try (FileChannel fc = FileChannel.open(file, CREATE, WRITE, TRUNCATE_EXISTING)) {
fc.write(ByteBuffer.wrap("HELLO".getBytes(StandardCharsets.UTF_8)));
} finally {
Files.delete(file);
}
} catch (IOException e) {
throw new UncheckedIOException(e);
}
}
}
|
