EMBEDDED模式下，开启tsdb，配置数据库url的地方有并发问题 #4018
Description
- I have searched the issues of this repository and believe that this is not a duplicate.
- I have checked the FAQ of this repository and believe that this is not a duplicate.
environment
- canal 1.1.4
- mysql version
Issue Description
otter中，同时开启多个canal实例，类CanalInstanceWithManager ，截图部分代码感觉有并发问题，会出现数据库连接url为空的情况
If there is an exception, please attach the exception trace:
pid:153 nid:83 exception:canal:test:com.alibaba.otter.canal.parse.exception.CanalParseException: apply failed caused by : Could not get JDBC Connection; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 10000, active 0, maxActive 30, creating 0
Caused by: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 10000, active 0, maxActive 30, creating 0
at org.springframework.orm.ibatis.SqlMapClientTemplate.execute(SqlMapClientTemplate.java:198)
at org.springframework.orm.ibatis.SqlMapClientTemplate.queryForObject(SqlMapClientTemplate.java:271)
at com.alibaba.otter.canal.parse.inbound.mysql.tsdb.dao.MetaSnapshotDAO.findByTimestamp(MetaSnapshotDAO.java:29)
at com.alibaba.otter.canal.parse.inbound.mysql.tsdb.DatabaseTableMeta.buildMemFromSnapshot(DatabaseTableMeta.java:403)
at com.alibaba.otter.canal.parse.inbound.mysql.tsdb.DatabaseTableMeta.rollback(DatabaseTableMeta.java:174)
at com.alibaba.otter.canal.parse.inbound.mysql.AbstractMysqlEventParser.processTableMeta(AbstractMysqlEventParser.java:137)
at com.alibaba.otter.canal.parse.inbound.AbstractEventParser$3.run(AbstractEventParser.java:200)
at java.lang.Thread.run(Thread.java:745)
Caused by: com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 10000, active 0, maxActive 30, creating 0
at com.alibaba.druid.pool.DruidDataSource.getConnectionInternal(DruidDataSource.java:1508)
at com.alibaba.druid.pool.DruidDataSource.getConnectionDirect(DruidDataSource.java:1253)
at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1233)
at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:1223)
at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:90)
at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111)
at org.springframework.orm.ibatis.SqlMapClientTemplate.execute(SqlMapClientTemplate.java:184)
... 7 more
Caused by: java.sql.SQLException: connect error, url , driverClass com.mysql.jdbc.Driver
at com.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1582)
at com.alibaba.druid.pool.DruidDataSource$CreateConnectionThread.run(DruidDataSource.java:2466)