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資料庫阿裡連接配接池 druid配置詳解

>轉載自http://blog.csdn.net/hj7jay/article/details/51686418

Java程式很大一部分要操作資料庫,為了提高性能操作資料庫的時候,有不得不使用資料庫連接配接池。資料庫連接配接池有很多選擇,c3p、dhcp、proxool等,druid作為一名後起之秀,憑借其出色的性能,也逐漸印入了大家的眼簾。接下來本教程就說一下druid的簡單使用。

首先從 http://repo1.maven.org/maven2/com/alibaba/druid/ 下載下傳最新的jar包。如果想使用最新的源碼編譯,可以從 https://github.com/alibaba/druid 下載下傳源碼,然後使用maven指令行,或者導入到eclipse中進行編譯。

和dbcp類似,druid的配置項如下

配置 預設值 說明
name

配置這個屬性的意義在于,如果存在多個資料源,監控的時候 

可以通過名字來區分開來。如果沒有配置,将會生成一個名字, 

格式是:”DataSource-” + System.identityHashCode(this)

jdbcUrl

連接配接資料庫的url,不同資料庫不一樣。例如: 

mysql : jdbc:mysql://10.20.153.104:3306/druid2  

oracle : jdbc:oracle:thin:@10.20.149.85:1521:ocnauto

username 連接配接資料庫的使用者名
password

連接配接資料庫的密碼。如果你不希望密碼直接寫在配置檔案中, 

可以使用ConfigFilter。詳細看這裡: 

https://github.com/alibaba/druid/wiki/%E4%BD%BF%E7%94%A8ConfigFilter

driverClassName 根據url自動識别 這一項可配可不配,如果不配置druid會根據url自動識别dbType,然後選擇相應的driverClassName
initialSize 初始化時建立實體連接配接的個數。初始化發生在顯示調用init方法,或者第一次getConnection時
maxActive 8 最大連接配接池數量
maxIdle 8 已經不再使用,配置了也沒效果
minIdle 最小連接配接池數量
maxWait

擷取連接配接時最大等待時間,機關毫秒。配置了maxWait之後, 

預設啟用公平鎖,并發效率會有所下降, 

如果需要可以通過配置useUnfairLock屬性為true使用非公平鎖。

poolPreparedStatements false

是否緩存preparedStatement,也就是PSCache。 

PSCache對支援遊标的資料庫性能提升巨大,比如說oracle。 

在mysql5.5以下的版本中沒有PSCache功能,建議關閉掉。

作者在5.5版本中使用PSCache,通過監控界面發現PSCache有緩存命中率記錄, 

該應該是支援PSCache。

maxOpenPreparedStatements -1

要啟用PSCache,必須配置大于0,當大于0時, 

poolPreparedStatements自動觸發修改為true。 

在Druid中,不會存在Oracle下PSCache占用記憶體過多的問題, 

可以把這個數值配置大一些,比如說100

validationQuery

用來檢測連接配接是否有效的sql,要求是一個查詢語句。 

如果validationQuery為null,testOnBorrow、testOnReturn、 

testWhileIdle都不會其作用。

testOnBorrow true 申請連接配接時執行validationQuery檢測連接配接是否有效,做了這個配置會降低性能。
testOnReturn false 歸還連接配接時執行validationQuery檢測連接配接是否有效,做了這個配置會降低性能
testWhileIdle false

建議配置為true,不影響性能,并且保證安全性。 

申請連接配接的時候檢測,如果空閑時間大于 

timeBetweenEvictionRunsMillis, 

執行validationQuery檢測連接配接是否有效。

timeBetweenEvictionRunsMillis

有兩個含義: 

1) Destroy線程會檢測連接配接的間隔時間 

2) testWhileIdle的判斷依據,詳細看testWhileIdle屬性的說明

numTestsPerEvictionRun 不再使用,一個DruidDataSource隻支援一個EvictionRun
minEvictableIdleTimeMillis
connectionInitSqls 實體連接配接初始化的時候執行的sql
exceptionSorter 根據dbType自動識别 當資料庫抛出一些不可恢複的異常時,抛棄連接配接
filters

屬性類型是字元串,通過别名的方式配置擴充插件, 

常用的插件有: 

監控統計用的filter:stat  

日志用的filter:log4j 

防禦sql注入的filter:wall

proxyFilters

類型是List<com.alibaba.druid.filter.Filter>, 

如果同時配置了filters和proxyFilters, 

是組合關系,并非替換關系

表1.1 配置屬性

加入 druid-1.0.9.jar

ApplicationContext.xml

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  1. < bean name = “transactionManager” class =“org.springframework.jdbc.datasource.DataSourceTransactionManager” >     
  2.     < property name = “dataSource” ref = “dataSource” ></ property >  
  3.      </ bean >  
  4.     < bean id = “propertyConfigurer” class =“org.springframework.beans.factory.config.PropertyPlaceholderConfigurer” >    
  5.        < property name = “locations” >    
  6.            < list >    
  7.                  < value > /WEB-INF/classes/dbconfig.properties </ value >    
  8.             </ list >    
  9.         </ property >    
  10.     </ bean >  
< bean name = "transactionManager" class ="org.springframework.jdbc.datasource.DataSourceTransactionManager" >   
    < property name = "dataSource" ref = "dataSource" ></ property >
     </ bean >
    < bean id = "propertyConfigurer" class ="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer" >  
       < property name = "locations" >  
           < list >  
                 < value > /WEB-INF/classes/dbconfig.properties </ value >  
            </ list >  
        </ property >  
    </ bean >
           

     ApplicationContext.xml配置druid   

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  1. <!– 阿裡 druid 資料庫連接配接池 –>  
  2.   < bean id = “dataSource” class = “com.alibaba.druid.pool.DruidDataSource”destroy-method = “close” >    
  3.        <!– 資料庫基本資訊配置 –>  
  4.        < property name = “url” value = “{url}"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span>&nbsp;</span><span class="tag-name">property</span><span>&nbsp;</span><span class="attribute">name</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">"username"</span><span>&nbsp;</span><span class="attribute">value</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">" />    
  5.        < property name = "username" value = "{username}” />    
  6.        < property name = “password” value = “{password}"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span>&nbsp;</span><span class="tag-name">property</span><span>&nbsp;</span><span class="attribute">name</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">"driverClassName"</span><span>&nbsp;</span><span class="attribute">value</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">" />    
  7.        < property name = "driverClassName" value = "{driverClassName}” />    
  8.        < property name = “filters” value = “{filters}"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="comments">&lt;!--&nbsp;最大并發連接配接數&nbsp;--&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span>&nbsp;</span><span class="tag-name">property</span><span>&nbsp;</span><span class="attribute">name</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">"maxActive"</span><span>&nbsp;</span><span class="attribute">value</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">" />    
  9.         <!-- 最大并發連接配接數 -->  
  10.        < property name = "maxActive" value = "{maxActive}” />  
  11.        <!– 初始化連接配接數量 –>  
  12.        < property name = “initialSize” value = “{initialSize}"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="comments">&lt;!--&nbsp;配置擷取連接配接等待逾時的時間&nbsp;--&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span>&nbsp;</span><span class="tag-name">property</span><span>&nbsp;</span><span class="attribute">name</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">"maxWait"</span><span>&nbsp;</span><span class="attribute">value</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">" />  
  13.        <!-- 配置擷取連接配接等待逾時的時間 -->  
  14.        < property name = "maxWait" value = "{maxWait}” />  
  15.        <!– 最小空閑連接配接數 –>  
  16.        < property name = “minIdle” value = “{minIdle}"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="comments">&lt;!--&nbsp;配置間隔多久才進行一次檢測,檢測需要關閉的空閑連接配接,機關是毫秒&nbsp;--&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span>&nbsp;</span><span class="tag-name">property</span><span>&nbsp;</span><span class="attribute">name</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">"timeBetweenEvictionRunsMillis"</span><span>&nbsp;</span><span class="attribute">value</span><span>&nbsp;=</span><span class="attribute-value">" />    
  17.        <!-- 配置間隔多久才進行一次檢測,檢測需要關閉的空閑連接配接,機關是毫秒 -->  
  18.        < property name = "timeBetweenEvictionRunsMillis" value ="{timeBetweenEvictionRunsMillis}” />  
  19.        <!– 配置一個連接配接在池中最小生存的時間,機關是毫秒 –>  
  20.        < property name = “minEvictableIdleTimeMillis” value =“{minEvictableIdleTimeMillis}"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span>&nbsp;</span><span class="tag-name">property</span><span>&nbsp;</span><span class="attribute">name</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">"validationQuery"</span><span>&nbsp;</span><span class="attribute">value</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">" />    
  21.        < property name = "validationQuery" value = "{validationQuery}” />    
  22.        < property name = “testWhileIdle” value = “{testWhileIdle}"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span>&nbsp;</span><span class="tag-name">property</span><span>&nbsp;</span><span class="attribute">name</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">"testOnBorrow"</span><span>&nbsp;</span><span class="attribute">value</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">" />    
  23.        < property name = "testOnBorrow" value = "{testOnBorrow}” />    
  24.        < property name = “testOnReturn” value = “{testOnReturn}"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span>&nbsp;</span><span class="tag-name">property</span><span>&nbsp;</span><span class="attribute">name</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">"maxOpenPreparedStatements"</span><span>&nbsp;</span><span class="attribute">value</span><span>&nbsp;=</span><span class="attribute-value">" />    
  25.        < property name = "maxOpenPreparedStatements" value ="{maxOpenPreparedStatements}” />  
  26.        <!– 打開 removeAbandoned 功能 –>  
  27.        < property name = “removeAbandoned” value = “{removeAbandoned}"</span><span>&nbsp;</span><span class="tag">/&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class=""><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="comments">&lt;!--&nbsp;1800&nbsp;秒,也就是&nbsp;30&nbsp;分鐘&nbsp;--&gt;</span><span>&nbsp;&nbsp;</span></span></li><li class="alt"><span>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="tag">&lt;</span><span>&nbsp;</span><span class="tag-name">property</span><span>&nbsp;</span><span class="attribute">name</span><span>&nbsp;=&nbsp;</span><span class="attribute-value">"removeAbandonedTimeout"</span><span>&nbsp;</span><span class="attribute">value</span><span>&nbsp;=</span><span class="attribute-value">" />  
  28.        <!-- 1800 秒,也就是 30 分鐘 -->  
  29.        < property name = "removeAbandonedTimeout" value ="{removeAbandonedTimeout}” />  
  30.        <!– 關閉 abanded 連接配接時輸出錯誤日志 –>     
  31.        < property name = “logAbandoned” value = “${logAbandoned}” />  
  32.   </ bean >  
<!-- 阿裡 druid 資料庫連接配接池 -->
    < bean id = "dataSource" class = "com.alibaba.druid.pool.DruidDataSource"destroy-method = "close" >  
         <!-- 資料庫基本資訊配置 -->
         < property name = "url" value = "${url}" />  
         < property name = "username" value = "${username}" />  
         < property name = "password" value = "${password}" />  
         < property name = "driverClassName" value = "${driverClassName}" />  
         < property name = "filters" value = "${filters}" />  
          <!-- 最大并發連接配接數 -->
         < property name = "maxActive" value = "${maxActive}" />
         <!-- 初始化連接配接數量 -->
         < property name = "initialSize" value = "${initialSize}" />
         <!-- 配置擷取連接配接等待逾時的時間 -->
         < property name = "maxWait" value = "${maxWait}" />
         <!-- 最小空閑連接配接數 -->
         < property name = "minIdle" value = "${minIdle}" />  
         <!-- 配置間隔多久才進行一次檢測,檢測需要關閉的空閑連接配接,機關是毫秒 -->
         < property name = "timeBetweenEvictionRunsMillis" value ="${timeBetweenEvictionRunsMillis}" />
         <!-- 配置一個連接配接在池中最小生存的時間,機關是毫秒 -->
         < property name = "minEvictableIdleTimeMillis" value ="${minEvictableIdleTimeMillis}" />  
         < property name = "validationQuery" value = "${validationQuery}" />  
         < property name = "testWhileIdle" value = "${testWhileIdle}" />  
         < property name = "testOnBorrow" value = "${testOnBorrow}" />  
         < property name = "testOnReturn" value = "${testOnReturn}" />  
         < property name = "maxOpenPreparedStatements" value ="${maxOpenPreparedStatements}" />
         <!-- 打開 removeAbandoned 功能 -->
         < property name = "removeAbandoned" value = "${removeAbandoned}" />
         <!-- 1800 秒,也就是 30 分鐘 -->
         < property name = "removeAbandonedTimeout" value ="${removeAbandonedTimeout}" />
         <!-- 關閉 abanded 連接配接時輸出錯誤日志 -->   
         < property name = "logAbandoned" value = "${logAbandoned}" />
    </ bean >
           

dbconfig.properties

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  1. url: jdbc:mysql:// localhost :3306/ newm  
  2. driverClassName: com.mysql.jdbc.Driver  
  3. username: root  
  4. password: root  
  5. filters: stat  
  6. maxActive: 20  
  7. initialSize: 1  
  8. maxWait: 60000  
  9. minIdle: 10  
  10. maxIdle: 15  
  11. timeBetweenEvictionRunsMillis: 60000  
  12. minEvictableIdleTimeMillis: 300000  
  13. validationQuery: SELECT ‘x’  
  14. testWhileIdle: true  
  15. testOnBorrow: false  
  16. testOnReturn: false  
  17. maxOpenPreparedStatements: 20  
  18. removeAbandoned: true  
  19. removeAbandonedTimeout: 1800  
  20. logAbandoned: true  
url: jdbc:mysql:// localhost :3306/ newm
driverClassName: com.mysql.jdbc.Driver
username: root
password: root
filters: stat
maxActive: 20
initialSize: 1
maxWait: 60000
minIdle: 10
maxIdle: 15
timeBetweenEvictionRunsMillis: 60000
minEvictableIdleTimeMillis: 300000
validationQuery: SELECT 'x'
testWhileIdle: true
testOnBorrow: false
testOnReturn: false
maxOpenPreparedStatements: 20
removeAbandoned: true
removeAbandonedTimeout: 1800
logAbandoned: true
           

web.xml

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  1. <!– 連接配接池 啟用 Web 監控統計功能    start–>  
  2.   < filter >  
  3.      < filter-name > DruidWebStatFilter </ filter-name >  
  4.      < filter-class > com.alibaba.druid.support.http.WebStatFilter </ filter-class >  
  5.      < init-param >  
  6.          < param-name > exclusions </ param-name >  
  7.          < param-value > *. js ,*. gif ,*. jpg ,*. png ,*. css ,*. ico ,/ druid /* </ param-value >  
  8.      </ init-param >  
  9.   </ filter >  
  10.   < filter-mapping >  
  11.      < filter-name > DruidWebStatFilter </ filter-name >  
  12.      < url-pattern > /* </ url-pattern >  
  13.   </ filter-mapping >  
  14.   < servlet >  
  15.      < servlet-name > DruidStatView </ servlet-name >  
  16.      < servlet-class > com.alibaba.druid.support.http.StatViewServlet </ servlet-class >  
  17.   </ servlet >  
  18.   < servlet-mapping >  
  19.      < servlet-name > DruidStatView </ servlet-name >  
  20.      < url-pattern > / druid /* </ url-pattern >  
  21.   </ servlet-mapping >  
  22.   <!– 連接配接池 啟用 Web 監控統計功能    end–>  
<!-- 連接配接池 啟用 Web 監控統計功能    start-->
    < filter >
       < filter-name > DruidWebStatFilter </ filter-name >
       < filter-class > com.alibaba.druid.support.http.WebStatFilter </ filter-class >
       < init-param >
           < param-name > exclusions </ param-name >
           < param-value > *. js ,*. gif ,*. jpg ,*. png ,*. css ,*. ico ,/ druid /* </ param-value >
       </ init-param >
    </ filter >
    < filter-mapping >
       < filter-name > DruidWebStatFilter </ filter-name >
       < url-pattern > /* </ url-pattern >
    </ filter-mapping >
    < servlet >
       < servlet-name > DruidStatView </ servlet-name >
       < servlet-class > com.alibaba.druid.support.http.StatViewServlet </ servlet-class >
    </ servlet >
    < servlet-mapping >
       < servlet-name > DruidStatView </ servlet-name >
       < url-pattern > / druid /* </ url-pattern >
    </ servlet-mapping >
    <!-- 連接配接池 啟用 Web 監控統計功能    end-->
           

通路監控頁面: http://ip:port/projectName/druid/index.html