Tag History Missing Data at Midnight

Hi,

Recently we've noticed that our Tag History data seems to have a consistent dead period starting at midnight and lasting a couple hours. See attachment:
https://imgur.com/a/JZyoK

The wrapper log around this time:

INFO | jvm 1 | 2017/12/18 00:01:03 | INFO [LocalDBManagerImpl ] [00:01:03,436]: Creating auto-backup of internal database "config.idb"...
INFO | jvm 1 | 2017/12/18 00:01:05 | INFO [LocalDBManagerImpl ] [00:01:05,106]: Created auto-backup of internal database "config.idb" in 1 seconds
INFO | jvm 1 | 2017/12/18 00:01:09 | INFO [ScheduledBackupManager ] [00:01:09,403]: Created scheduled backup successfully.
INFO | jvm 1 | 2017/12/18 00:01:09 | INFO [ScheduledBackupManager ] [00:01:09,494]: Removed 1 old autobackup(s).
INFO | jvm 1 | 2017/12/18 00:01:13 | ERROR [TagHistoryDatasourceSink ] [00:01:13,414]: Error rolling back transaction.
INFO | jvm 1 | 2017/12/18 00:01:13 | com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.
INFO | jvm 1 | 2017/12/18 00:01:13 | at sun.reflect.GeneratedConstructorAccessor109.newInstance(Unknown Source)
INFO | jvm 1 | 2017/12/18 00:01:13 | at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
INFO | jvm 1 | 2017/12/18 00:01:13 | at java.lang.reflect.Constructor.newInstance(Unknown Source)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.mysql.jdbc.Util.getInstance(Util.java:386)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1014)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:988)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:974)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:919)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.mysql.jdbc.ConnectionImpl.throwConnectionClosedException(ConnectionImpl.java:1290)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.mysql.jdbc.ConnectionImpl.checkClosed(ConnectionImpl.java:1282)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.mysql.jdbc.ConnectionImpl.rollback(ConnectionImpl.java:4975)
INFO | jvm 1 | 2017/12/18 00:01:13 | at org.apache.commons.dbcp.DelegatingConnection.rollback(DelegatingConnection.java:328)
INFO | jvm 1 | 2017/12/18 00:01:13 | at org.apache.commons.dbcp.PoolingDataSource$PoolGuardConnectionWrapper.rollback(PoolingDataSource.java:312)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.inductiveautomation.ignition.gateway.datasource.SRConnectionWrapper.rollback(SRConnectionWrapper.java:434)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.inductiveautomation.ignition.gateway.history.sinks.AbstractDatasourceSink.storeToDatasource(AbstractDatasourceSink.java:136)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.inductiveautomation.ignition.gateway.history.sinks.AbstractDatasourceSink.storeData(AbstractDatasourceSink.java:99)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.inductiveautomation.ignition.gateway.history.sinks.AggregateSink.storeData(AggregateSink.java:147)
INFO | jvm 1 | 2017/12/18 00:01:13 | at com.inductiveautomation.ignition.gateway.history.forwarders.ForwarderThread.run(ForwarderThread.java:138)
INFO | jvm 1 | 2017/12/18 00:01:13 | Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

Eventually leading to many repeats of this...

"Error storing tag history.
INFO | jvm 1 | 2017/12/17 00:44:09 | java.lang.Exception: Unable to add data to memory buffer, buffer full."

Ignition V7.7

Any advice would be appreciated.

Regards,
Alan

com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.

Is your database running a scheduled backup at midnight?

@PGriffith Thanks for the reply.

We are using MySQL and have not made any changes on the database side.
The event scheduler is disabled and a scheduled backup has never been configured.

Could it be Ignition causing the connection status to change for whatever reason, making it appear that the connection is closed - i.e. causing that line of error?

Kind Regards,
Alan