MySQL中 Too many connections错误的解决办法

Mysql的错误,待解决[已解决]Data source rejected establishment of connection message from server: "Too many connections";

[15:22:53,461] [CustomExceptionHandler,44] - Handle Exception:Hibernate operation: Cannot open connection; uncategorized SQLException for SQL [???]; SQL state [08004]; error code [1040]; Data source rejected establishment of connection message from server:
"Too many connections"; nested exception is java.sql.SQLException: Data source rejected establishment of connection message from server: "Too many connections"

org.springframework.jdbc.UncategorizedSQLException: Hibernate operation: Cannot open connection; uncategorized SQLException for SQL [???]; SQL state [08004]; error code [1040]; Data source rejected establishment of connection message from server: "Too many
connections"; nested exception is java.sql.SQLException: Data source rejected establishment of connection message from server: "Too many connections"

java.sql.SQLException: Data source rejected establishment of connection message from server: "Too many connections"

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1997)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:1906)

at com.mysql.jdbc.MysqlIO.secureAuth411(MysqlIO.java:2535)

at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:817)

at com.mysql.jdbc.Connection.createNewIO(Connection.java:1782)

at com.mysql.jdbc.Connection.<init>(Connection.java:450)

at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:411)

at java.sql.DriverManager.getConnection(DriverManager.java:525)

at java.sql.DriverManager.getConnection(DriverManager.java:140)

at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriverManager(DriverManagerDataSource.java:291)

at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriverManager(DriverManagerDataSource.java:277)

at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnectionFromDriverManager(DriverManagerDataSource.java:259)

at org.springframework.jdbc.datasource.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:241)

at org.springframework.orm.hibernate3.LocalDataSourceConnectionProvider.getConnection(LocalDataSourceConnectionProvider.java:80)

at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:315)

at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:109)

at org.hibernate.jdbc.AbstractBatcher.prepareQueryStatement(AbstractBatcher.java:105)

at org.hibernate.loader.Loader.prepareQueryStatement(Loader.java:1561)

at org.hibernate.loader.Loader.doQuery(Loader.java:661)

at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:224)

at org.hibernate.loader.Loader.doList(Loader.java:2150)

at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2029)

at org.hibernate.loader.Loader.list(Loader.java:2024)

at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:369)

at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:300)

at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:146)

at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1093)

at org.hibernate.impl.QueryImpl.list(QueryImpl.java:79)

at com.easou.framework.dao.hibernate.BaseDAOHibernate.pageListQuery(BaseDAOHibernate.java:164)

at com.vitamin.cn.manager.news.dao.hibernate.NewsDAOHibernate.searchNews(NewsDAOHibernate.java:38)

at com.vitamin.cn.manager.news.bl.impl.NewsManagerImpl.searchNews(NewsManagerImpl.java:24)

at com.vitamin.cn.manager.news.action.NewsAction.listNews(NewsAction.java:88)

at com.vitamin.cn.manager.news.action.NewsAction.execute(NewsAction.java:35)

at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419)

at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)

at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)

at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)

at com.easou.framework.util.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:88)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:524)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)

at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:199)

at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:282)

at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:767)

at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:697)

at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:889)

at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)

at java.lang.Thread.run(Thread.java:595)

1.可能是mysql的max connections设置的问题

2.可能是多次insert,update操作没有关闭session,需要在spring里配置transaction支持。

解决:

1.修改tomcat里的session 的time-out时间减少为20,(不是必改项)

2.对处理量大的对数据库insert或update的操作提供transaction支持.

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下面的是解决办法：

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Data source rejected establishment of connection, message from server: "Too many connections"

原因：

因为你的mysql安装目录下的my.ini中设定的并发连接数太少或者系统繁忙导致连接数被占满

解决方式：

打开MYSQL安装目录打开MY.INI找到max_connections（在大约第93行）默认是100 一般设置到500～1000比较合适，重启mysql,这样1040错误就解决啦。
max_connections=1000

一定要重新启动MYSQL才能生效

CMD->

net stop mysql

net start mysql

 

关于改变innodb_log_file_size后无法启动mysql的问题

innodb_buffer_pool_size=768M

innodb_log_file_size=256M

innodb_log_buffer_size=8M

innodb_additional_mem_pool_size=4M

innodb_flush_log_at_trx_commit=0

innodb_thread_concurrency=20

以上是对innodb引擎的初步优化, 发现是更新innodb_log_file_size=256M时候出现了问题，只要加上这个就无法启动,

后来才知道原来要STOP服务先，然后再删除原来的文件………

打开/MySQL Server 5.5/data

删除ib_logfile0, ib_logfile1........ib_logfilen
再开启选项，成功启动。