SQL Server has encountered 1 occurrence(s) of cachestore flush

SQL Server Log report from one of our production server was continuously showing following messages.

Log Date	Process Info	Process Text
2012-07-23T20:00:08.880	spid17s	SQL Server has encountered 1 occurrence(s) of cachestore flush for the 'Bound Trees' cachestore (part of plan cache) due to some database maintenance or reconfigure operations.
2012-07-23T20:00:08.880	spid17s	SQL Server has encountered 1 occurrence(s) of cachestore flush for the 'SQL Plans' cachestore (part of plan cache) due to some database maintenance or reconfigure operations.
2012-07-23T20:00:07.190	spid17s	SQL Server has encountered 1 occurrence(s) of cachestore flush for the 'Object Plans' cachestore (part of plan cache) due to some database maintenance or reconfigure operations.
2012-07-23T06:00:04.640	spid16s	SQL Server has encountered 1 occurrence(s) of cachestore flush for the 'Bound Trees' cachestore (part of plan cache) due to some database maintenance or reconfigure operations.
2012-07-23T06:00:04.640	spid16s	SQL Server has encountered 1 occurrence(s) of cachestore flush for the 'SQL Plans' cachestore (part of plan cache) due to some database maintenance or reconfigure operations.
2012-07-23T06:00:04.580	spid16s	SQL Server has encountered 1 occurrence(s) of cachestore flush for the 'Object Plans' cachestore (part of plan cache) due to some database maintenance or reconfigure operations.

It happens when you configure user database with Auto Close option.

SQL Server, close a user database automatically, when last session is closed and reactivated when a login request is received.  We must keep this option OFF for a better performance. Why so read this.

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