NHibernate + MySql Intermittent TimeoutException

Question

Je viens de migrer mon application NHibernate de SQL Server vers MySQL. Tout semble bien sauf que je reçois des exceptions Timeout intermittentes. Je peux trouver beaucoup d'informations sur ces délais avec MySql et même one blog post sur les délais d'attente avec Hibernate + MySql + C3PO (quel qu'il soit). Mais rien sur la façon de modifier NHib pour arrêter ce problème. Savez-vous?

Voici la trace de la pile:

NHibernate.TransactionException: Begin failed with SQL exception ---> System.TimeoutException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond ---> System.IO.IOException: Unable to read data from the transport connection: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. ---> System.Net.Sockets.SocketException: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 
    at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags) 
    at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) 
    --- End of inner exception stack trace --- 
    at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) 
    at MyNetworkStream.Read(Byte[] buffer, Int32 offset, Int32 count) 
    --- End of inner exception stack trace --- 
    at MyNetworkStream.HandleOrRethrowException(Exception e) 
    at MyNetworkStream.Read(Byte[] buffer, Int32 offset, Int32 count) 
    at MySql.Data.MySqlClient.TimedStream.Read(Byte[] buffer, Int32 offset, Int32 count) 
    at System.IO.BufferedStream.Read(Byte[] array, Int32 offset, Int32 count) 
    at MySql.Data.MySqlClient.MySqlStream.ReadFully(Stream stream, Byte[] buffer, Int32 offset, Int32 count) 
    at MySql.Data.MySqlClient.MySqlStream.LoadPacket() 
    at MySql.Data.MySqlClient.MySqlStream.ReadPacket() 
    at MySql.Data.MySqlClient.NativeDriver.ReadOk(Boolean read) 
    at MySql.Data.MySqlClient.NativeDriver.SetDatabase(String dbName) 
    at MySql.Data.MySqlClient.Driver.SetDatabase(String dbName) 
    at MySql.Data.MySqlClient.MySqlConnection.ChangeDatabase(String databaseName) 
    at MySql.Data.MySqlClient.MySqlConnection.Open() 
    at NHibernate.Connection.DriverConnectionProvider.GetConnection() 
    at NHibernate.AdoNet.ConnectionManager.GetConnection() 
    at NHibernate.Impl.SessionImpl.get_Connection() 
    at NHibernate.Transaction.AdoTransaction.Begin(IsolationLevel isolationLevel) 
    --- End of inner exception stack trace --- 
    at NHibernate.Transaction.AdoTransaction.Begin(IsolationLevel isolationLevel) 
    at NHibernate.Transaction.AdoTransaction.Begin() 
    at NHibernate.AdoNet.ConnectionManager.BeginTransaction() 
    at NHibernate.Impl.SessionImpl.BeginTransaction() 

Answer 1

Je lance NHibernate sur un nuage Rackspace avec une base de données MYSQL. J'ai trouvé que je recevais des délais d'attente en raison du fait que les connexions étaient laissées à moitié ouvertes en raison du sommeil. Finalement, je manquais de connexions et mon site Web a expiré.

À la fin, j'ai ajouté Pooling=false; dans ma chaîne de connexion. Je ne suis pas sûr si c'est le correctif final mais il a arrêté mon problème.

Vous pouvez vérifier les connexions à dormir en utilisant show processlist dans un éditeur MySQL ...