1 /*

     2  * Copyright (c) 2017, 2018, Red Hat, Inc. All rights reserved.

     3  *

     4  * This code is free software; you can redistribute it and/or modify it

     5  * under the terms of the GNU General Public License version 2 only, as

     6  * published by the Free Software Foundation.

     7  *

     8  * This code is distributed in the hope that it will be useful, but WITHOUT

     9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    11  * version 2 for more details (a copy is included in the LICENSE file that

    12  * accompanied this code).

    13  *

    14  * You should have received a copy of the GNU General Public License version

    15  * 2 along with this work; if not, write to the Free Software Foundation,

    16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    17  *

    18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    19  * or visit www.oracle.com if you need additional information or have any

    20  * questions.

    21  *

    22  */

    23 

    24 /**

    25  * @test TestMemoryMXBeans

    26  * @key gc

    27  * @requires vm.gc.Epsilon

    28  * @summary Test JMX memory beans

    29  * @modules java.base/jdk.internal.misc

    30  *          java.management

    31  * @run main/othervm -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC          -Xmx1g TestMemoryMXBeans   -1 1024

    32  * @run main/othervm -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC -Xms1g   -Xmx1g TestMemoryMXBeans 1024 1024

    33  * @run main/othervm -XX:+UnlockExperimentalVMOptions -XX:+UseEpsilonGC -Xms128m -Xmx1g TestMemoryMXBeans  128 1024

    34  */

    35 

    36 import java.lang.management.*;

    37 import java.util.*;

    38 

    39 public class TestMemoryMXBeans {

    40 

    41     static volatile Object sink;

    42 

    43     public static void main(String[] args) throws Exception {

    44         if (args.length < 2) {

    45             throw new IllegalStateException("Should provide expected heap sizes");

    46         }

    47 

    48         long initSize = 1L * Integer.parseInt(args[0]) * 1024 * 1024;

    49         long maxSize =  1L * Integer.parseInt(args[1]) * 1024 * 1024;

    50 

    51         testMemoryBean(initSize, maxSize);

    52         testAllocs();

    53     }

    54 

    55     public static void testMemoryBean(long initSize, long maxSize) {

    56         MemoryMXBean memoryMXBean = ManagementFactory.getMemoryMXBean();

    57         long heapInit = memoryMXBean.getHeapMemoryUsage().getInit();

    58         long heapMax = memoryMXBean.getHeapMemoryUsage().getMax();

    59         long nonHeapInit = memoryMXBean.getNonHeapMemoryUsage().getInit();

    60         long nonHeapMax = memoryMXBean.getNonHeapMemoryUsage().getMax();

    61 

    62         if (initSize > 0 && heapInit != initSize) {

    63             throw new IllegalStateException("Init heap size is wrong: " + heapInit + " vs " + initSize);

    64         }

    65         if (maxSize > 0 && heapMax != maxSize) {

    66             throw new IllegalStateException("Max heap size is wrong: " + heapMax + " vs " + maxSize);

    67         }

    68     }

    69 

    70     public static void testAllocs() {

    71         MemoryMXBean memoryMXBean = ManagementFactory.getMemoryMXBean();

    72 

    73         // Do lazy inits first:

    74         long heapUsed1 = memoryMXBean.getHeapMemoryUsage().getUsed();

    75         sink = new int[1024*1024];

    76         long heapUsed2 = memoryMXBean.getHeapMemoryUsage().getUsed();

    77 

    78         // Compute how much we waste during the calls themselves:

    79         heapUsed1 = memoryMXBean.getHeapMemoryUsage().getUsed();

    80         heapUsed2 = memoryMXBean.getHeapMemoryUsage().getUsed();

    81         long adj = heapUsed2 - heapUsed1;

    82 

    83         heapUsed1 = memoryMXBean.getHeapMemoryUsage().getUsed();

    84         sink = new int[1024*1024];

    85         heapUsed2 = memoryMXBean.getHeapMemoryUsage().getUsed();

    86 

    87         long diff = heapUsed2 - heapUsed1 - adj;

    88         long min = 8 + 4*1024*1024;

    89         long max = 16 + 4*1024*1024;

    90         if (!(min <= diff && diff <= max)) {

    91            throw new IllegalStateException("Allocation did not change used space right: " + diff + " should be in [" + min + ", " + max + "]");

    92         }

    93     }

    94 

    95 }