记一次MySQL创建数据库连接时提示数据库超时问题_failed to obtain jdbc connection; nested exception

首先看一下报错信息：

Caused by: org.apache.ibatis.exceptions.PersistenceException: 
### Error querying database.  Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 6000, active 0, maxActive 20, creating 1, createElapseMillis 364404, createErrorCount 9
### The error may exist in com/jovision/vse/console/storage/mapper/StoragePackageMapper.java (best guess)
### The error may involve com.jovision.vse.console.storage.mapper.StoragePackageMapper.selectList
### The error occurred while executing a query
### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 6000, active 0, maxActive 20, creating 1, createElapseMillis 364404, createErrorCount 9
    at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:149)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140)
    at sun.reflect.GeneratedMethodAccessor177.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:426)
    ... 108 common frames omitted
Caused by: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 6000, active 0, maxActive 20, creating 1, createElapseMillis 364404, createErrorCount 9
    at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:82)
    at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:80)
    at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:67)
    at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:337)
    at com.baomidou.mybatisplus.core.executor.MybatisSimpleExecutor.prepareStatement(MybatisSimpleExecutor.java:93)
    at com.baomidou.mybatisplus.core.executor.MybatisSimpleExecutor.doQuery(MybatisSimpleExecutor.java:68)
    at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:325)
    at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
    at com.baomidou.mybatisplus.core.executor.MybatisCachingExecutor.query(MybatisCachingExecutor.java:165)
    at com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor.intercept(MybatisPlusInterceptor.java:64)
    at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:61)
    at com.sun.proxy.$Proxy216.query(Unknown Source)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:147)
    ... 113 common frames omitted
Caused by: com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 6000, active 0, maxActive 20, creating 1, createElapseMillis 364404, createErrorCount 9
    at com.alibaba.druid.pool.DruidDataSource.getConnectionInternal(DruidDataSource.java:1720)
    at com.alibaba.druid.pool.DruidDataSource.getConnectionDirect(DruidDataSource.java:1402)
    at com.alibaba.druid.filter.FilterChainImpl.dataSource_connect(FilterChainImpl.java:5059)
    at com.alibaba.druid.filter.stat.StatFilter.dataSource_getConnection(StatFilter.java:680)
    at com.alibaba.druid.filter.FilterChainImpl.dataSource_connect(FilterChainImpl.java:5055)
    at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1380)
    at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1372)
    at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:109)
    at org.springframework.jdbc.datasource.DataSourceUtils.fetchConnection(DataSourceUtils.java:158)
    at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:116)
    at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:79)
    ... 125 common frames omitted
Caused by: java.sql.SQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 100 times. Giving up.
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:110)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:89)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:63)
    at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:73)
    at com.mysql.cj.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:905)
    at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:830)
    at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:455)
    at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:240)
    at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:199)
    at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:156)
    at com.alibaba.druid.filter.stat.StatFilter.connection_connect(StatFilter.java:218)
    at com.alibaba.druid.filter.FilterChainImpl.connection_connect(FilterChainImpl.java:150)
    at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1646)
    at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1710)
    at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2753)
Caused by: com.mysql.cj.exceptions.CJException: Access denied for user 'mix'@'localhost' (using password: YES)
    at sun.reflect.GeneratedConstructorAccessor93.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:61)
    at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:105)
    at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:151)
    at com.mysql.cj.exceptions.ExceptionFactory.createException(ExceptionFactory.java:129)
    at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:816)
    at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:741)
    at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:709)
    at com.mysql.cj.protocol.a.NativeProtocol.checkErrorMessage(NativeProtocol.java:132)
    at com.mysql.cj.protocol.a.NativeAuthenticationProvider.proceedHandshakeWithPluggableAuthentication(NativeAuthenticationProvider.java:540)
    at com.mysql.cj.protocol.a.NativeAuthenticationProvider.connect(NativeAuthenticationProvider.java:202)
    at com.mysql.cj.protocol.a.NativeProtocol.connect(NativeProtocol.java:1449)
    at com.mysql.cj.NativeSession.connect(NativeSession.java:165)
    at com.mysql.cj.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:849)
    ... 10 common frames omitted
 

根据报错日志来看是创建连接的时候异常，而且active连接为0，并没有超过数据库的最大连接数。

输入命令show variables like '%max_connection%';

问题偶先，并没有找到复现过程，该问题持续定位中····