mysql - grails tomcat jndi 的最佳 mysql 数据源属性

JNDI、mysql 5.6 和 tomcat 7 的大多数示例都在 DataSource.groovy 中定义了这一点:

dataSource {
   pooled = true
   driverClassName = "com.mysql.jdbc.Driver"
   dialect = 'org.hibernate.dialect.MySQL5InnoDBDialect'
}
environments:
   production {
        dataSource {
        dbCreate = "update"
        jndiName = "java:comp/env/myDatasourceName
    }
}

并在 tomcat 的 conf/context.xml 中:

<Context>
   <WatchedResource>WEB-INF/web.xml</WatchedResource>
      <Resource name="myDatasourceName" auth="Container" type="javax.sql.DataSource"
       maxActive="100" maxIdle="30" maxWait="10000"
       username="root" password="password" driverClassName="com.mysql.jdbc.Driver"
       url="jdbc:mysql://localhost:3306/my_db_name"/>
 </Context>

问题是，对于基本的小批量生产系统来说，这是正确的设置吗，如果数据库出现故障然后又出现等情况，它应该重新连接吗？

在 DataSource.xml 中有一个非常复杂的例子:

    dataSource {
        dbCreate = "update"
        //url = "jdbc:h2:prodDb;MVCC=TRUE;LOCK_TIMEOUT=10099;DB_CLOSE_ON_EXIT=FALSE"
        properties {
           // Documentation for Tomcat JDBC Pool
           // http://tomcat.apache.org/tomcat-7.0-doc/jdbc-pool.html#Common_Attributes
           // https://tomcat.apache.org/tomcat-7.0-doc/api/org/apache/tomcat/jdbc/pool/PoolConfiguration.html
           jmxEnabled = true
           initialSize = 5
           maxActive = 50
           minIdle = 5
           maxIdle = 25
           maxWait = 10000
           maxAge = 10 * 60000
           timeBetweenEvictionRunsMillis = 5000
           minEvictableIdleTimeMillis = 60000
           validationQuery = "SELECT 1"
           validationQueryTimeout = 3
           validationInterval = 15000
           testOnBorrow = true
           testWhileIdle = true
           testOnReturn = false
           ignoreExceptionOnPreLoad = true
           // http://tomcat.apache.org/tomcat-7.0-doc/jdbc-pool.html#JDBC_interceptors
           jdbcInterceptors = "ConnectionState;StatementCache(max=200)"
           defaultTransactionIsolation = java.sql.Connection.TRANSACTION_READ_COMMITTED // safe default
           // controls for leaked connections
           abandonWhenPercentageFull = 100 // settings are active only when pool is full
           removeAbandonedTimeout = 120000
           removeAbandoned = true
           // use JMX console to change this setting at runtime
           logAbandoned = false // causes stacktrace recording overhead, use only for debugging
           /*
           // JDBC driver properties
           // Mysql as example
           dbProperties {
               // Mysql specific driver properties
               // http://dev.mysql.com/doc/connector-j/en/connector-j-reference-configuration-properties.html
               // let Tomcat JDBC Pool handle reconnecting
               autoReconnect=false
               // truncation behaviour
               jdbcCompliantTruncation=false
               // mysql 0-date conversion
               zeroDateTimeBehavior='convertToNull'
               // Tomcat JDBC Pool's StatementCache is used instead, so disable mysql driver's cache
               cachePrepStmts=false
               cacheCallableStmts=false
               // Tomcat JDBC Pool's StatementFinalizer keeps track
               dontTrackOpenResources=true
               // performance optimization: reduce number of SQLExceptions thrown in mysql driver code
               holdResultsOpenOverStatementClose=true
               // enable MySQL query cache - using server prep stmts will disable query caching
               useServerPrepStmts=false
               // metadata caching
               cacheServerConfiguration=true
               cacheResultSetMetadata=true
               metadataCacheSize=100
               // timeouts for TCP/IP
               connectTimeout=15000
               socketTimeout=120000
               // timer tuning (disable)
               maintainTimeStats=false
               enableQueryTimeouts=false
               // misc tuning
               noDatetimeStringSync=true
           }
           */
        }
    }

现在我不知道其中 95% 的参数是做什么的，但我想我需要它们全部？

我不明白的是这个

肯定 tomcat 会汇集连接，所以应该在 grails 数据源中 pooled=true 吗？

肯定tomcat会处理连接的重连和验证，那么为什么要定义validationQuery = "SELECT 1"呢？特别是在 mysql dbPrperties 部分中说“autoREconnect=false”。

有人能想出一个适用于少数用户的mysql的通用默认数据源定义吗？我可以调整最小/最大事件/空闲等，但这不是在 tomcat 中完成的，不是在 grails 中完成的吗？

"userServerPrepStmts=false"为什么有人要禁用准备好的语句？在过去的 15 年里，我们一直在训练只使用准备好的语句，否则数据库无法缓存它们。

如果我忽略所有这个复杂的例子，并使用每个人都发布的 super 简单的方法，它会正常工作吗？例如当数据库下降和上升时它会重新连接吗？会不会漏水等

谢谢!

最佳答案

AFAIK，Tomcat 与管理数据库连接无关。由于 Grails 2.3.6 ，这些是推荐的默认数据源属性:

properties {
  //see http://grails.org/doc/latest/guide/conf.html#dataSource for documentation
   jmxEnabled = true
   initialSize = 5
   maxActive = 50
   minIdle = 5
   maxIdle = 25
   maxWait = 10000
   maxAge = 10 * 60000
   timeBetweenEvictionRunsMillis = 5000
   minEvictableIdleTimeMillis = 60000
   validationQuery = "SELECT 1"
   validationQueryTimeout = 3
   validationInterval = 15000
   testOnBorrow = true
   testWhileIdle = true
   testOnReturn = false
   jdbcInterceptors = "ConnectionState;StatementCache(max=200)"
   defaultTransactionIsolation = java.sql.Connection.TRANSACTION_READ_COMMITTED
}