jdk8-mips64-public/hotspot: test/gc/7072527/TestFullGCCount.java@41e6ee74f879 (annotated)

test/gc/7072527/TestFullGCCount.java@41e6ee74f879 (annotated)

test/gc/7072527/TestFullGCCount.java

Tue, 02 Aug 2011 14:37:35 +0100

author: kevinw
date: Tue, 02 Aug 2011 14:37:35 +0100
changeset 3025: 41e6ee74f879
child 5008: bfe3be9ebd6c
permissions: -rw-r--r--

7072527: CMS: JMM GC counters overcount in some cases
Summary: Avoid overcounting when CMS has concurrent mode failure.
Reviewed-by: ysr
Contributed-by: rednaxelafx@gmail.com

 /*
  * Copyright (c) 2011, 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.
  */
 /*
  * @test TestFullGCount.java
  * @bug 7072527
  * @summary CMS: JMM GC counters overcount in some cases
  * @run main/othervm -XX:+UseConcMarkSweepGC TestFullGCCount
  *
  */
 import java.util.*;
 import java.lang.management.*;
 public class TestFullGCCount {
     public String collectorName = "ConcurrentMarkSweep";
     public static void main(String [] args) {
         TestFullGCCount t = null;
         if (args.length==2) {
             t = new TestFullGCCount(args[0], args[1]);
         } else {
             t = new TestFullGCCount();
         }
         System.out.println("Monitoring collector: " + t.collectorName);
         t.run();
     }
     public TestFullGCCount(String pool, String collector) {
         collectorName = collector;
     }
     public TestFullGCCount() {
     }
     public void run() {
         int count = 0;
         int iterations = 20;
         long counts[] = new long[iterations];
         boolean diffAlways2 = true; // assume we will fail
         for (int i=0; i<iterations; i++) {
             System.gc();
             counts[i] = getCollectionCount();
             if (i>0) {
                 if (counts[i] - counts[i-1] != 2) {
                     diffAlways2 = false;
                 }
             }
         }
         if (diffAlways2) {
             throw new RuntimeException("FAILED: System.gc must be incrementing count twice.");
         }
         System.out.println("Passed.");
     }
     private long getCollectionCount() {
         long count = 0;
         List<MemoryPoolMXBean> pools = ManagementFactory.getMemoryPoolMXBeans();
         List<GarbageCollectorMXBean> collectors = ManagementFactory.getGarbageCollectorMXBeans();
         for (int i=0; i<collectors.size(); i++) {
             GarbageCollectorMXBean collector = collectors.get(i);
             String name = collector.getName();
             if (name.contains(collectorName)) {
                 System.out.println(name + ": collection count = "
                                    + collector.getCollectionCount());
                 count = collector.getCollectionCount();
             }
         }
         return count;
     }
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

test/gc/7072527/TestFullGCCount.java@41e6ee74f879 (annotated)

test/gc/7072527/TestFullGCCount.java