1 /*

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     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

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     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  *

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    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

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    23 

    24 /*

    25  * @test TestMBeanCMS.java

    26  * @bug 6581734

    27  * @requires vm.gc.ConcMarkSweep

    28  * @summary CMS Old Gen's collection usage is zero after GC which is incorrect

    29  * @modules java.management

    30  * @run main/othervm -Xmx512m -verbose:gc -XX:+UseConcMarkSweepGC TestMBeanCMS

    31  *

    32  */

    33 

    34 import java.lang.management.GarbageCollectorMXBean;

    35 import java.lang.management.ManagementFactory;

    36 import java.lang.management.MemoryPoolMXBean;

    37 import java.util.LinkedList;

    38 import java.util.List;

    39 

    40 // 6581734 states that memory pool usage via the mbean is wrong

    41 // for CMS (zero, even after a collection).

    42 //

    43 // 6580448 states that the collection count similarly is wrong

    44 // (stays at zero for CMS collections)

    45 // -- closed as dup of 6581734 as the same fix resolves both.

    46 

    47 

    48 public class TestMBeanCMS {

    49 

    50     private String poolName = "CMS";

    51     private String collectorName = "ConcurrentMarkSweep";

    52 

    53     public static void main(String [] args) {

    54 

    55         TestMBeanCMS t = null;

    56         if (args.length==2) {

    57             t = new TestMBeanCMS(args[0], args[1]);

    58         } else {

    59             System.out.println("Defaulting to monitor CMS pool and collector.");

    60             t = new TestMBeanCMS();

    61         }

    62         t.run();

    63     }

    64 

    65     public TestMBeanCMS(String pool, String collector) {

    66         poolName = pool;

    67         collectorName = collector;

    68     }

    69 

    70     public TestMBeanCMS() {

    71     }

    72 

    73     public void run() {

    74         // Use some memory, enough that we expect collections should

    75         // have happened.

    76         // Must run with options to ensure no stop the world full GC,

    77         // but e.g. at least one CMS cycle.

    78         allocationWork(300*1024*1024);

    79         System.out.println("Done allocationWork");

    80 

    81         // Verify some non-zero results are stored.

    82         List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();

    83         int poolsFound = 0;

    84         int poolsWithStats = 0;

    85         for (int i=0; i<pools.size(); i++) {

    86             MemoryPoolMXBean pool = pools.get(i);

    87             String name = pool.getName();

    88             System.out.println("found pool: " + name);

    89 

    90             if (name.contains(poolName)) {

    91                 long usage = pool.getCollectionUsage().getUsed();

    92                 System.out.println(name + ": usage after GC = " + usage);

    93                 poolsFound++;

    94                 if (usage > 0) {

    95                     poolsWithStats++;

    96                 }

    97             }

    98         }

    99         if (poolsFound == 0) {

   100             throw new RuntimeException("No matching memory pools found: test with -XX:+UseConcMarkSweepGC");

   101         }

   102 

   103         List<GarbageCollectorMXBean> collectors = ManagementFactory.getGarbageCollectorMXBeans();

   104         int collectorsFound = 0;

   105         int collectorsWithTime= 0;

   106         for (int i=0; i<collectors.size(); i++) {

   107             GarbageCollectorMXBean collector = collectors.get(i);

   108             String name = collector.getName();

   109             System.out.println("found collector: " + name);

   110             if (name.contains(collectorName)) {

   111                 collectorsFound++;

   112                 System.out.println(name + ": collection count = "

   113                                    + collector.getCollectionCount());

   114                 System.out.println(name + ": collection time  = "

   115                                    + collector.getCollectionTime());

   116                 if (collector.getCollectionCount() <= 0) {

   117                     throw new RuntimeException("collection count <= 0");

   118                 }

   119                 if (collector.getCollectionTime() > 0) {

   120                     collectorsWithTime++;

   121                 }

   122             }

   123         }

   124         // verify:

   125         if (poolsWithStats < poolsFound) {

   126             throw new RuntimeException("pools found with zero stats");

   127         }

   128 

   129         if (collectorsWithTime<collectorsFound) {

   130             throw new RuntimeException("collectors found with zero time");

   131         }

   132         System.out.println("Test passed.");

   133     }

   134 

   135     public void allocationWork(long target) {

   136 

   137         long sizeAllocated = 0;

   138         List list = new LinkedList();

   139         long delay = 50;

   140         long count = 0;

   141 

   142         while (sizeAllocated < target) {

   143             int size = 1024*1024;

   144             byte [] alloc = new byte[size];

   145             if (count % 2 == 0) {

   146                 list.add(alloc);

   147                 sizeAllocated+=size;

   148                 System.out.print(".");

   149             }

   150             try { Thread.sleep(delay); } catch (InterruptedException ie) { }

   151             count++;

   152         }

   153     }

   154 

   155 }