发布时间：2025-06-24 19:17:59  作者：北方职教升学中心  阅读量：182

druid根据堆栈或连接池连接 Druidatasource追溯源代码c;使用spring.datasource.druid.socket-timeout配置存在参数覆盖问题c;即使使用connect-timeout配置也无法解决这种异常。

polarDB/mysql实例配置 connect_timeout参数超过10秒，connect-timeout等超时配置�以下：

#springmysql配置.datasource.type = com.alibaba.druid.pool.DruidDataSource#spring.datasource.druid.driverClassName = net.sf.log4jdbc.sql.jdbcapi.DriverSpyspring.datasource.druid.driverClassName = com.mysql.cj.jdbc.Driver#mysql 8.x使用 spring.datasource.druid.urlspring.datasource.druid.url = jdbc:mysql://xxx:3306/xxx?serverTimezone=GMT+8&characterEncoding=utf8&autoReconnect=truespring.datasource.druid.username = xxxspring.datasource.druid.password = xxxspring.datasource.druid.initial-size = 5spring.datasource.druid.min-idle = 10spring.datasource.druid.max-active = 500spring.datasource.druid.max-wait = 30000spring.datasource.druid.connect-timeout = 30000spring.datasource.druid.query-timeout = 30000spring.datasource.druid.transaction-query-timeout = 30000spring.datasource.druid.time-between-eviction-runs-millis = 60000spring.datasource.druid.min-evictable-idle-time-millis = 30000spring.datasource.druid.max-evictable-idle-time-millis = 90000spring.datasource.druid.test-while-idle = truespring.datasource.druid.test-on-borrow = falsespring.datasource.druid.test-on-return = falsespring.datasource.druid.validation-query = select 1spring.datasource.druid.webStatFilter.enabled = truespring.datasource.druid.stat-view-servlet.enabled = truespring.datasource.druid.stat-view-servlet.url-pattern = /druid/*spring.datasource.druid.stat-view-servlet.reset-enable = falsespring.datasource.druid.filter.stat.enabled = truespring.datasource.druid.filter.stat.log-slow-sql = truespring.datasource.druid.filter.stat.slow-sql-millis = 1000spring.datasource.druid.filter.stat.merge-sql = truespring.datasource.druid.filter.wall.config.multi-statement-allow = true。
不区分业务高峰，只要慢sql超过一定时间（本例为10秒）连接池参数和polarDB实例参数配置如何更新？c;异常仍然存在。是执行数据库的更新和异常查询。开发人员也需要对其进行评估和优化。
背景。
现象。查询条件、执行优化器等有很大关系c;db版本࿰编码优化、重启服务解决问题。注意，这种方法只解决类似൪
The last packet successfully received from the server was 10,011 milliseconds ago. The last packet sent successfully to the server was 10,011 milliseconds ago.。
最后在druidgithub上 在issue中发现了高度相似的问题，以下解决方案如下：a;
sockettimeout参数在连接配置url中增加如下c;
spring.datasource.druid.url = jdbc:mysql://xxx:3306/xxx?serverTimezone=Asia/Shanghai&characterEncoding=utf8&useSSL=false&autoReconnect=true&socketTimeout=30000。索引优化或升级修复执行器索引c;同时，
根据ChatGPT或在线搜索解决方案，优化了连接池的大小、#xff1b;
问题得不到解决c;业务层处理索引优化和强制索引，一些数据迁移到ES//IOTDB，但根本问题是MYSQL中仍然存在不可避免的大表慢sql，这个问题仍然存在。
"异常提示问题。时间参数和回收配置c;如max-wait、
异常如下：
### Cause: com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failureThe last packet successfully received from the server was 10,011 milliseconds ago. The last packet sent successfully to the server was 10,011 milliseconds ago.; Communications link failureThe last packet successfully received from the server was 10,011 milliseconds ago. The last packet sent successfully to the server was 10,011 milliseconds ago.; nested exception is com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failureThe last packet successfully received from the server was 10,011 milliseconds ago. The last packet sent successfully to the server was 10,011 milliseconds ago.	at org.springframework.jdbc.support.SQLExceptionSubclassTranslator.doTranslate(SQLExceptionSubclassTranslator.java:100)	at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:73)	at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:82)	at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:91)	at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:441)	at com.sun.proxy.$Proxy152.selectList(Unknown Source)	at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:224)	at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.executeForIPage(MybatisMapperMethod.java:121)	at com.baomidou.mybatisplus.core.override.MybatisMapperMethod.execute(MybatisMapperMethod.java:85)	at com.baomidou.mybatisplus.core.override.MybatisMapperProxy$PlainMethodInvoker.invoke(MybatisMapperProxy.java:148)	at com.baomidou.mybatisplus.core.override.MybatisMapperProxy.invoke(MybatisMapperProxy.java:89)	at com.sun.proxy.$Proxy535.selectPage(Unknown Source)	at sun.reflect.Generatedmethodaccessor2431.invoke(Unknown Source)	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)。
polarDB/mysql实例配置 connect超过10秒的timeout参数b;
问题得不到解决c;业务层处理索引优化和强制索引，一些数据迁移到ES//IOTDB，但根本问题是MYSQL中仍然存在不可避免的大表慢sql，这个问题还是存在的。至于为什么部分查询没有索引导致慢sql超时问题󿀌它与索引顺序结构、
解决方案记录。
polardBÿ在线使用c;基于mysql(5.7)，Springbot+mybatisplus+durid连接器，部分业务场景涉及大表更新和查询操作c;查询慢sql并在一定时间内报告"Communications link failure"异常，大量数据主要体现在界面查询或定期任务处理中，