The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.) at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1549) ~[tomcat-dbcp.
在Mysql的默认设置中,如果一个数据库连接超过8小时没有使用(闲置8小时,即 28800s),mysql server将主动断开这条连接,后续在该连接上进行的查询操作都将失败,将 出现:error 2006 (MySQL server has gone away)!. 查看mysql server超时时间: msyql> show global variables like '%timeout%'; 设置mysql server超时时间(以秒为单位):
应用服务器连接mysql,有时候会出现以下异常: at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [na:1.7.0_95] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [na:1.7.0_95] at java.lang.Thread.run(Thread.
mysql每次建立一个socket连接(connect)时,这个socket都会占用一定内存.即使你关闭(close)连接时,并不是真正的关闭,而是处于睡眠(sleep)状态. 当你下次再进行连接时,就可以快速启动当前处于睡眠状态的socket.但是过多的socket会占用大量的内存,为解决这个问题,mysql有个超时机制. 你可以使用这条语句查看当前设置的超时时间长度: show global variables like 'wait_timeout'; 得到的结果如下: +---------
小结: 1.mysql服务端主动关闭链接的秒数: MySQL :: MySQL 8.0 Reference Manual :: 5.1.8 Server System Variables https://dev.mysql.com/doc/refman/8.0/en/server-system-variables.html#sysvar_interactive_timeout interactive_timeout Property Value Command-Line Format --int
日志报错: No operations allowed after connection closed.; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed. 解决办法: 对数据库进行如下配置即可: dataSource.setTimeBetweenEvictionRunsMi
备注:这是在pm2配置node环境下,超过8小时mysql自动关闭的情况下出现的解决方法:1.封装mysql.js var mysql = require('mysql'); var connection = { host: '',//主机名 user: '',//用户名 password: '',//密码 database: ''//数据库 } // 用于保存数据连接实例 var db = null; var pingInterval; // 如果数据连接出错,则重新连接 function h
使用Hibernate + MySQL数据库开发,链接超时问题: com.mysql.jdbc.CommunicationsException: The last packet successfully received from the server was58129 seconds ago.The last packet sent successfully to the server was 58129 seconds ago, which is longer than the server
com.mysql.jdbc.CommunicationsException: The last packet successfully received from the server was58129 seconds ago.The last packet sent successfully to the server was 58129 seconds ago, which is longer than the server configured value of 'wait_timeou
bug回顾 : 想必大家在用MySQL时都会遇到连接超时的问题,如下图所示: ### Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 47,795,922 milliseconds ago. The last packet sent successfully to the server was 47,7