Connection unexpectedly terminated

I have a very simple SQL query statement but it needs to be run many times. I get following error randomly, maybe once per one hundred times.

MySql.Data.MySqlClient.MySqlException: Connection unexpectedly terminated.     at MySql.Data.MySqlClient.MySqlStream.LoadPacket()     at MySql.Data.MySqlClient.MySqlStream.OpenPacket()     at MySql.Data.MySqlClient.NativeDriver.Authenticate411()     at MySql.Data.MySqlClient.NativeDriver.Authenticate()     at MySql.Data.MySqlClient.NativeDriver.Open()     at MySql.Data.MySqlClient.Driver.Create(MySqlConnectionStringBuilder settings)     at MySql.Data.MySqlClient.MySqlConnection.Open()  

Following thread http://bugs.mysql.com/bug.php?id=6688 mentioned that Since the bug seems to be strongly connected to some timeout, I've tried to manipulate several server variables which are related to timeout settings. I found out that if the value of the variable net_write_timeout is increased to 3600 (previously 60) the error does not occur!



it is talked about how to set the net_write_timeout

 [Test] public void Bug45978() { 	MySqlCommand command = OpenConnectionAndCreateCommand(); 	command.CommandText = "SET net_write_timeout = 1"; 	command.ExecuteNonQuery(); 	command.CommandText = "SELECT BlaBla FROM bigtable LIMIT 100000"; 	using (MySqlDataReader reader = command.ExecuteReader()) 	{ 		Thread.Sleep(2000); 		// after this several cycles of DataReader.Read() are executed  		// normally and then the problem, described above, occurs 		while (reader.Read()) 		{ 			object o = reader[0]; 		} 	} }

In the last a couple of days website running, I got the above error happened for 664 times. I will set the net_write_timeout value and see whether the condition gets better.

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