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Hadoop-0.20.1+Ubuntu9.10实战

Tue, 15 Dec 2009 14:46:00 GMT

�l�过几个晚上的奋战，Hadoop-0.20.1+Ubuntu9.10实战�l�于出炉�?

目录�Q?
一、环境准�?1
二、安装JDK6 1
三、配�|�SSH 2
四、安装配�|�hadoop 4
4.1下蝲及安�?4
4.2配置 4
4.2.1配置$HADOOP_HOME/conf/hadoop-env.sh 4
4.2.2配置$HADOOP_HOME/conf/core-site.xml 4
4.2.3配置$HADOOP_HOME/conf/mapred-site.xml 5
4.2.4格式化namenode 5
4.3启动及验�?5
五、跑�W�一个wordcount例子 7
4.1准备工作 7
4.2�q�行例子 8
4.3看结�?11
4.4在eclipse中调�?�q�行 12
4.5分析代码 15
六、改�q�的wordcount例子 17
参�?23
FAQ 23
1、xxx is not in the sudoers file解决�Ҏ�� 23
2�?etc/sudoers is mode 0640, should be 0440怎么回事�Q?24
3、如何增加ubuntu的SWAP�I�间�Q?24
4、bin/hadoop dfs到底有哪些命令？ 25

原文和文档我攑֜�了javaeye�Q�这里给个链接吧�Q?br /> http://itstarting.javaeye.com/blog/520985

IT�q�行�?/a> 2009-12-15 22:46 发表评论

Tue, 15 Dec 2009 14:44:00 GMT

1�?span lang="EN-US">JDK安装配置

选用最新的版本6.0.

打开�l�端�Q�执行以下命令：

sudo apt-get install sun-java6-jdk

按照提示做就是了�?/span>

配置JAVA环境变量:

sudo gedit /etc/environment

在其中添加如下两行：

CLASSPATH=.:/usr/lib/jvm/java-6-sun/lib

JAVA_HOME=/usr/lib/jvm/java-6-sun

执行命��o�Q?/span>sudo gedit /etc/jvm�Q�在最前面加入�Q?/span>

/usr/lib/jvm/java-6-sun

2�?span lang="EN-US">Tomcat安装配置

�q�是喜欢�l�典�?/span>Tomcat5.5,�?/span>http://tomcat.apache.org��M��载�?/span>

文�g为：apache-tomcat-5.5.28.zip

解压�~�：

unzip /home/zhengxq/下蝲/apache-tomcat-5.5.28.zip -d $HOME/java

3�?span lang="EN-US">Eclipse安装配置

下蝲最新的版本�Q��ƈ解压�~�：

zhengxq@zhengxq-desktop:~$ tar zxf $HOME/下蝲/eclipse-java-galileo-SR1-linux-gtk.tar.gz -C $HOME/java

此时直接通过$HOME/java/eclipse/eclipse卛_��启动�?/span>

Tomcat插�g是必��ȝ��Q�下载�ƈ解压�~�到eclipse/plugins下，重启eclipse卛_��?/span>

下面�?/span>“高�񔽋?/span>“�Q�）。�ؓ了徏立更方便的导航，可以�q�样�Q?/span>

    1、在/usr/bin目录下创��Z��个启动脚�?/span>eclipse�Q?/span>

    sudo gedit /usr/bin/eclipse

    然后在该文�g中添加以下内容：

    #!/bin/sh
    export MOZILLA_FIVE_HOME="/usr/lib/mozilla/"
    export ECLIPSE_HOME="/home/zhengxq/java/eclipse"
    $ECLIPSE_HOME/eclipse $*

    2、让修改该脚本的权限�Q�让它变成可执行�Q?/span>

    sudo chmod +x /usr/bin/eclipse

    3、在桌面或�?/span>gnome菜单中添�?/span>eclipse启动图标
    �Q?/span>1�Q�在桌面或者启动面板上��d��图标�Q?/span>
    在桌面（右键单击桌面->创徏启动器）或面板（右键单击面板->��d��到面�?/span> ->定制应用�E�序启动器）上创��Z��个新的启动器�Q�然后添加下列数据：
    名称�Q?/span>Eclipse Platform
    命��o�Q?/span>eclipse
    图标�Q?/span> /home/zhengxq/java/eclipse/icon.xpm
    �Q?/span>2�Q�在Applications�Q�应用程序）菜单上添加一个图�?/span>
    用文本编辑器�?/span>/usr/share/applications目录里新��Z��个名�?/span>eclipse.desktop的启动器�Q�如下面的命�?/span>:
    sudo gedit /usr/share/applications/eclipse.desktop
    然后在文件中��d��下列内容�Q?/span>

[Desktop Entry]
Encoding=UTF-8
Name=Eclipse Platform
Comment=Eclipse IDE
Exec=eclipse
Icon=/home/zhengxq/java/eclipse/icon.xpm
Terminal=false
StartupNotify=true
Type=Application
Categories=Application;Development;

保存文�g�Q�此时即可通过双击桌面eclipse的图标来�q�行eclipse�?/span>

注意�Q?/span> Type=Application后面�l�对不能有空��|��否则��Z��来可别抓狂�?/span>

IT�q�行�?/a> 2009-12-15 22:44 发表评论

Tue, 15 Dec 2009 14:43:00 GMT

—�?span lang="EN-US">IT �q�行�?span lang="EN-US">(Email & MSN:zhengxianquan AT hotmail.com)

说在前面的话�Q?/strong> 作�ؓ一名技术�h员，喜欢通过自己的实战去学习�Q�也��L��了写学习�W�记的习惯。个人做企业应用更多�Q�也涉及TB�U�别的非�l�构化数据，对于Hadoop倒是�W�一�ơ接触，分布式计��d��有用武之地。但�q�个�W�记只能说是自己的盲学，��是��单的看看�?/span>

Keywords�Q�Hadoop; HDFS; 学习�W�记

目录�Q?br /> 1. 准备工作 2
1.1. Supported Platforms 2
1.2. Hadoop需要的基础东西 2
1.3. 安装Cygwin注意事项 2
2. 单机上配�|�过�E?nbsp;3
2.1. 配置SSH 3
2.1.1. 配置服务 3
2.1.2. 启动Cygwin sshd服务 4
2.1.3. Setup authorization keys 5
2.2. 修订/配置/conf/core-site.xml 7
2.3. 修订/配置/conf/mapred-site.xml 9
2.4. 修订/配置\conf\masters和slaves 9
2.5. 修订/配置\conf\hadoop-env.sh 9
2.6. 其他数据节点�c�M��Q�重复即�?nbsp;10
3. 格式化及启动 10
3.1. 启动命��o 10
3.2. 如何验证启动成功 11
4. 使用及开�?nbsp;12
4.1. 常用命��o行��用方�?nbsp;12
4.2. 可以通过��览器访�?nbsp;15
5. FAQ 16
5.1. ��Z��么启动不了？ 16
5.2. 配置文�g可能��D��的问�?nbsp;17
5.3. JobTracker一直有问题�Q?nbsp;19
5.4. 如何验证配置�q�启动成功？ 19
6. 常用命��o 20
7. 参�?nbsp;21
地址�Q?a >http://itstarting.javaeye.com/blog/513659

IT�q�行�?/a> 2009-12-15 22:43 发表评论

工作��?0�U�基本模式的理解

Tue, 15 Dec 2009 14:38:00 GMT
Aalst提出了工作流�?0�U�基本模式�?
如果不知道的可参考《Workflow Patterns-2002�?/p>
工作��?0�U�基本模式的理解�Q�当然了�Q�后人陆�l�扩展、变化，模式数量不断变化�Q�但万变不离其宗�Q�可从这些基本模式看��P��

下面是我的初步分析：

模式名称

模式关键�?/span>

模式说明

Basic Control Patterns

Sequence

Sequence

1

Parallel Split

AND Split

2

Synchronization

AND Join

3

Exclusive Choice

XOR Split

4

Simple Merge

XOR Join

5

ADVANCED BRANCHING AND SYNCHRONIZATION PATTERNS

Multiple Choice

OR Split

6

Synchronizing Merge

AND Join

7

Multi-merge

OR Join(+Multi)

8�Q?/span>

Discriminator

OR Join(+Reset/Ignore)

9

N-out-of-M-join

OR Join(+Multi M)

9a�Q?/span>N分支�Q?/span>M聚合卛_��

STRUCTURAL PATTERNS

Arbitrary Cycles[自由循环]

XOR Split

10

Implicit Termination

Multi(OR/AND) Split End

11

PATTERNS INVOLVING MULTIPLE INSTANCES

MI without synchronization

Runtime independent thread by condition

12�Q�在�q�行期创建独立实例（�U�程、程序等�Q?/span>

MI with a priori known design time knowledge

Design time priori Instance

13�Q�设计期多实例，且需全部完成

MI with a priori known runtime knowledge

Runtime multi Instance by condition/free

14�Q�运行期可基于条件创建多实例

MI with no a priori runtime knowledge

Runtime multi Instance free by people

15�Q�运行期可手工随意创建多实例

STATE-BASED PATTERNS

Deferred Choice

XOR Split(By choice)

16�Q?#8220;推着�?#8221;��程�Q�或��Z��既定条�g分支

Interleaved Parallel Routing

OR Split + OR Join, Parallel

17�Q�多分支聚合�Q�分支执行顺序由�q�行期确�?/span>

Milestone

Wait by Milestone

18�Q�在“里程��?#8221;节点�{�待

CANCELLATION PATTERNS

Cancel Activity

Cancel in specified Activity

19�Q�在指定的活动取�?/span>

Cancel Case

Cancel Anywhere/Anytime

20�Q��Q意时候可取消

可以看到�Q�其实很多是�c�M��的，�q��ؓ下一步的工作��引擎需求、设计打下基��?/p>
抛砖引玉�Q�供大家参考�?/p>

IT�q�行�?/a> 2009-12-15 22:38 发表评论

Endnote 9 中开发�ƈ使用自己的Style

Mon, 31 Aug 2009 15:14:00 GMT

1、基于现成的某个Style�q�行针对性的开发（�q�个开发说白了��是�l�合自己论文格式的要求不停的重复�Q�修�?lt;->验证�Q�，保存��q��Style�Q�如“郑式.ens”�Q�；
2、把Style文�g�Q�如“郑式.ens”�Q�放到\EndNote9\Styles目录下；
3、重新启用EndNote�Q?br /> 4�?span style="font-family: 宋体">打开Open Style Manager…
5�?span style="font-family: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">选中我的Style�Q�如“郑式.ens”�Q�，此时通过选中“郑氏”启用样式�Q?br />

附上样式文�g�Q�适合��大��士论文的编写要求（其他学校是否�W�合�Q�未知）�Q?a title="郑式.rar" href="/Files/itstarting/zheng.rar">/Files/itstarting/zheng.rar

IT�q�行�?/a> 2009-08-31 23:14 发表评论

Portal产品介绍--开放源码Portal产品

Wed, 15 Apr 2009 05:19:00 GMT
     摘要: 无论是商业化的还是开源的Portal产品�Q�符合国际标准规范是必不可少的要求。有的Portal可能不支持WSRP(Web Services for Remote Portlets)�Q�但必须�W�合JSR-168标准。比较突出的开源Portal主要有JBoss Portal、Apache Jetspeet-2�Q�Liferay Portal�Q�还有两个属于欧�z�的非美产品eXo Platform和GridSph...  阅读全文

IT�q�行�?/a> 2009-04-15 13:19 发表评论

Sun, 12 Apr 2009 13:55:00 GMT
Q�Q�WORD莫名其妙的所有引用（如Endnote和插入PPT对象�Q�都变成了域代码�Q�怎么办？
A�Q�工�?>选项->视图�Q?#8220;域代�?#8221;�Q�把它前面的对勾��L��卛_��Q?br /> 备注�Q�我居然��试了一�ơ一个一个选择“切换域代�?#8221;�Q�篏��M��不说�Q�居焉��新打开又这��P��晕死�?br />
参考：http://zhidao.baidu.com/question/75336298.html

IT�q�行�?/a> 2009-04-12 21:55 发表评论

Thu, 19 Feb 2009 12:24:00 GMT

AIX下用nmon�q�行监控和分析实�?br />
nmon从这里下载：
http://www.ibm.com/developerworks/wikis/display/Wikiptype/nmonanalyser

1、准�?/strong>�Q?br /> 1�Q�用root用户��d��到系�l�中
2�Q�徏目录�Q?mkdir /nmon/script
3�Q�确定版本：#oslevel�Q�以便确定用哪个脚本�Q�我是用530
        # oslevel -s
            5300-09-01-0847
4�Q�把nmon12e_aix530用ftp上传�?nmon/script
5�Q�执行授权命令：#chmod +x nmon12e_aix530

2、��?/strong>�Q?br /> 1�Q�直接��用：
./nmon/nmon12e_aix536 -f -N -m /nmon/log -s 30 -c 2880
表示�Q?br />   -f 按标准格式输出文�Ӟ��_YYYYMMDD_HHMM.nmon
  -N include NFS sections
  -m 切换到�\径去保存日志文�g
  -s 每隔n�U�抽样一�ơ，�q�里�?0
  -c 取出多少个抽��h��量，�q�里�?880�Q�即监控=2880*(30/60/60)=24��时
   �Ҏ��时计算�q�个数字的公式�ؓ�Q�c=h*3600/s�Q�比如要监控10��时�Q�每�?0�U�采样一�ơ，则c=10*3600/30=1200

2�Q�用crontab定期使用�Q?br /> A、执行命令：#crontab -e
B、在最后一行添加如下命令：
  0 8 * * 1,2,3,4,5 /nmon/script/nmon12e_aix530 -f -N -m /nmon/log -s 30 -c 1200
表示�Q?br />   周一到周五，从早�?8点开始，监控10个小�Ӟ��?8:00整�ؓ止）�Q�输出到/nmon/log

3、分�?br /> 1�Q�会�?tmp/nmon生成*.nmon的文件把它下载到你的电脑�?br /> 2�Q�打开nmon analyser v339.xls�Q�把宏的安全性设成最低，打开下蝲好的*.nmon文�g�?br />      �q�且保存��Z��个文�Ӟ��生成的是视图模式的，非常直观�Q?br />

参考：
附录一�Q�crontab参数�Q?br /> 参考：http://tech.ddvip.com/2008-11/122629526990895.html
    f1 f2 f3 f4 f5 program
minute hour day_of_month month weekday command�q�些字段接收以下��|��
minute 0 �?59
hour 0 �?23
day_of_month 1 �?31
month 1 �?12
weekday 0 �?6�Q�星期天到星期六�Q?

其中f1 是表�C�分钟，f2 表示��时�Q�f3 表示一个月份中的第几日�Q�f4 表示月䆾�Q�f5 表示一个星期中的第几天。program 表示要执行的�E�序�?br /> 　　 �?f1 �?* 时表�C�每分钟都要执行 program�Q�f2 �?* 时表�C�每��时都要执行�E�序�Q�其馀�c�L��
　　 �?f1 �?a-b 时表�C�Z��W?a 分钟到第 b 分钟�q�段旉��内要执行�Q�f2 �?a-b 时表�C�Z��W?a 到第 b ��时都要执行�Q�其馀�c�L��
　　 �?f1 �?*/n 时表�C�每 n 分钟个时间间隔执行一�ơ，f2 �?*/n 表示�?n ��时个时间间隔执行一�ơ，光��c�L��
　　 �?f1 �?a, b, c,... 时表�C�第 a, b, c,... 分钟要执行，f2 �?a, b, c,... 时表�C�第 a, b, c...个小时要执行�Q�其馀�c�L��

附录二：nmon参数�Q?br /> 参考http://www.ibm.com/developerworks/wikis/display/Wikiptype/nmonanalyser
nmon:
-f           spreadsheet output format [note: default -s300 -c288]
           Output file is _YYYYMMDD_HHMM.nmon

       -F same as -f but user supplied filename
-c    number of snapshots
-d     requests disk service and wait times (DISKSERV and DISKWAIT)
-i Ignore processes using less than this amount of CPU when generating TOP section – useful for reducing data volumes
-g file containing disk group definitions
-l number of hdisks per sheet - defaults to 150, maximum 250. See notes
-m
   NMON changes to this directory before saving the file
-r goes into spreadsheet file [default hostname]
-s interval between snap shots
-x   capacity planning (15 mins for 1 day = -fdt -s900 -c96)
-t           include top processes in the output
-T           as –t plus saves command line arguments in UARG section
-A         include data for async I/O (PROCAIO) sections
-D prevents DISK sections being produced (useful when Disk Groups are being used because there are too many hdisks to process)
-E         stops ESS sections being produced (necessary when Disk Groups are being used because there are too many vpaths to process)
-J prevents JFS sections being produced (prevents Excel errors when you have more than 255 filesystems)
-L includes LARGEPAGE section
-N include NFS sections
-S include WLM sections with subclasses
-W include WLM sections without subclasses
-Y include SUMMARY section (very efficient alternative to –t if PID level data is not required)

        example: nmon_aix51 -F asterix.nmon -r Test1 -s6 -c12

IT�q�行�?/a> 2009-02-19 20:24 发表评论

如何在WebLogic 8.1.6环境中查找有�q�接池泄漏的代码

Wed, 12 Nov 2008 16:41:00 GMT

解决�q�接池泄漏步�?/span>

��d��weblogic console, %Domain% -> Services -> JDBC -> Connection Pools -> jdbc/ioa

Configuration��?/span> -> Connection, 点开Advanced Options, 修改以下配置��状态：

配置��名�U?/span>

默认�?/span>

修改�?/span>

说明

Enable Connection Leak Profiling

��用

启用

开启连接池泄漏的监控�?/span>

Enable Connection Profiling

��用

启用

开启连接池监控�?/span>

Inactive Connection Timeout

0

100

�q�接在指定时间内�Q�单位：�U�）没有�z�d��的话�Q?/span>WebLogic会将之释攑�ƈ回收到连接池�?/span>

    以上配置��修改后不媄响在跑的应用�Q�不需要重启服务器或应用（配置��前没有黄色��图�?/span> �Q?/span>WebLogic很明��的告诉我们�q�个配置是不需要重启的�Q�，所以大可放心设�|�。只是启用监控后会对性能有一些媄响，具体影响会有多大�Q�我没有��试�q�，但开启这些设�|�只是暂时的�Q�得到日志后我们��可以把配置�q�原会默认倹{�?br />

在没有解册��接池泄漏问题之前�Q�如果没有请求时�q�接池将一直保持�ؓ0�Q�不会再有连接池满造成��h��无法响应的问题，我们也不用担心再挨客户骂�Q�也为我们解决问题争取了宝贵到时间�?/span>

       好了�Q�下面才是关键�?/span>

       �q�一�D�|��间后�Q�在bea\user_projects\domains\%domainname%\%servername%目录下，打开%servername%.log�Q�查找，"A JDBC pool connection leak was detected"�Q�如�?/span>WebLogic已经监控到有�q�接池泄漏的话，��可以找��C��下日志，�q�且很清楚的告诉我们在哪一个类的哪行代码创��Z��q�接�Q�但没有关闭�Q�注意红色加�_�字体）�Q?/span>

2008-5-22 上午11�?/span>47�?/span>20�U?/span> CST       Warning     JDBC                A JDBC pool connection leak was detected. A connection leak occurs when a connection obtained from the pool was not closed explicitly by calling close() and then was disposed by the garbage collector and returned to the connection pool. The following stack trace at create shows where the leaked connection was created. Stack trace at connection create:

       at weblogic.jdbc.wrapper.PoolConnection.init(PoolConnection.java:75)

       at weblogic.jdbc.pool.Driver.allocateConnection(Driver.java:254)

       at weblogic.jdbc.pool.Driver.connect(Driver.java:84)

       at weblogic.jdbc.jts.Driver.getNonTxConnection(Driver.java:546)

       at weblogic.jdbc.jts.Driver.connect(Driver.java:140)

       at weblogic.jdbc.common.internal.RmiDataSource.getConnection(RmiDataSource.java:344)

       at com.cp.fw.dao.BaseDAO.getConnection(BaseDAO.java:78)

       at com.cp.fw.dao.dataset.DataSetOp.init(DataSetOp.java:78)

       at com.cp.fw.dao.dataset.DataSetOp.(DataSetOp.java:45)

       at com.cp.ia.util.WorkFlowUtil.getNextWrokFlowId(WorkFlowUtil.java:93)

       at

……



       另外一�U�方法：

�?/span>WebLogic Console�Q�展开 %DomainName% -> Servers -> %ServerName%�Q�选到Logging – Server��，在页面最下方点击 "View server log"�Q�同��h��?/span> "A JDBC pool connection leak was detected"�Q�也可以扑ֈ�同样的日志�?/span>

WebLogic对于日志事�g的说明：

Message ID

BEA-001074

Subsystem

JDBC

Message

A JDBC pool connection leak was detected. A

connection leak occurs when a connection obtained

from the pool was not closed explicitly by calling

close() and then was disposed by the garbage

collector and returned to the connection pool. The

following stack trace at create shows where the

leaked connection was created. Stack trace at

connection create:

Detail

A JDBC pool connection leak was detected. A

connection leak occurs when a connection obtained

from the pool was not closed explicitly by calling

close() and then was disposed by the garbage

collector and returned to the connection pool. A

stack trace is printed indicating where the leaked

connection was created.

Cause

A JDBC pool connection leak was detected. A

connection leak occurs when a connection obtained

from the pool was not closed explicitly by calling

close() and then was disposed by the garbage

collector and returned to the connection pool. A

stack trace is printed indicating where the leaked

connection was created.

Action

Close the connection appropriately.

原文�Q�http://blog.csdn.net/esky2000/archive/2008/07/22/2689929.aspx

IT�q�行�?/a> 2008-11-13 00:41 发表评论

模式名称	模式关键�?/span>	模式说明
Basic Control Patterns
Sequence	Sequence	1
Parallel Split	AND Split	2
Synchronization	AND Join	3
Exclusive Choice	XOR Split	4
Simple Merge	XOR Join	5
ADVANCED BRANCHING AND SYNCHRONIZATION PATTERNS
Multiple Choice	OR Split	6
Synchronizing Merge	AND Join	7
Multi-merge	OR Join(+Multi)	8�Q?/span>
Discriminator	OR Join(+Reset/Ignore)	9
N-out-of-M-join	OR Join(+Multi M)	9a�Q?/span>N分支�Q?/span>M聚合卛_��
STRUCTURAL PATTERNS
Arbitrary Cycles[自由循环]	XOR Split	10
Implicit Termination	Multi(OR/AND) Split End	11
PATTERNS INVOLVING MULTIPLE INSTANCES
MI without synchronization	Runtime independent thread by condition	12�Q�在�q�行期创建独立实例（�U�程、程序等�Q?/span>
MI with a priori known design time knowledge	Design time priori Instance	13�Q�设计期多实例，且需全部完成
MI with a priori known runtime knowledge	Runtime multi Instance by condition/free	14�Q�运行期可基于条件创建多实例
MI with no a priori runtime knowledge	Runtime multi Instance free by people	15�Q�运行期可手工随意创建多实例
STATE-BASED PATTERNS
Deferred Choice	XOR Split(By choice)	16�Q?#8220;推着�?#8221;��程�Q�或��Z��既定条�g分支
Interleaved Parallel Routing	OR Split + OR Join, Parallel	17�Q�多分支聚合�Q�分支执行顺序由�q�行期确�?/span>
Milestone	Wait by Milestone	18�Q�在“里程��?#8221;节点�{�待
CANCELLATION PATTERNS
Cancel Activity	Cancel in specified Activity	19�Q�在指定的活动取�?/span>
Cancel Case	Cancel Anywhere/Anytime	20�Q��Q意时候可取消

配置��名�U?/span>	默认�?/span>	修改�?/span>	说明
Enable Connection Leak Profiling	��用	启用	开启连接池泄漏的监控�?/span>
Enable Connection Profiling	��用	启用	开启连接池监控�?/span>
Inactive Connection Timeout	0	100	�q�接在指定时间内�Q�单位：�U�）没有�z�d��的话�Q?/span>WebLogic会将之释攑�ƈ回收到连接池�?/span>

Message ID	BEA-001074
Subsystem	JDBC
Message	A JDBC pool connection leak was detected. A connection leak occurs when a connection obtained from the pool was not closed explicitly by calling close() and then was disposed by the garbage collector and returned to the connection pool. The following stack trace at create shows where the leaked connection was created. Stack trace at connection create:
Detail	A JDBC pool connection leak was detected. A connection leak occurs when a connection obtained from the pool was not closed explicitly by calling close() and then was disposed by the garbage collector and returned to the connection pool. A stack trace is printed indicating where the leaked connection was created.
Cause	A JDBC pool connection leak was detected. A connection leak occurs when a connection obtained from the pool was not closed explicitly by calling close() and then was disposed by the garbage collector and returned to the connection pool. A stack trace is printed indicating where the leaked connection was created.
Action	Close the connection appropriately.