在ASP.NET应用程序中使用out-of-process会话状态的SQL Server的连接问题

我有几个ASP.NET应用程序部署在一个农场的4 Windows 2003机器。每个应用程序在IIS中使用单独的应用程序池和虚拟目录。它们严重依赖于在单个SQL Server 2000(< sessionstate mode =“sqlserver”... />)上持久化的会话。应用程序是针对.NET 3.0编译的，但是.NET 3.5 SP1安装在服务器上。

每个Web服务器接收大约10个请求/秒。每隔一段时间我在日志中得到一些例外：

System.Data.SqlClient.SqlException: A transport-level error has occurred when receiving results from the server. (provider: TCP Provider,error: 0 - The semaphore timeout period has expired.)
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception,Boolean breakConnection)
   at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception,Boolean breakConnection)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)
   at System.Data.SqlClient.TdsParserStateObject.ReadSniError(TdsParserStateObject stateObj,UInt32 error)
   at System.Data.SqlClient.TdsParserStateObject.ReadSni(DbAsyncResult asyncResult,TdsParserStateObject stateObj)
   at System.Data.SqlClient.TdsParserStateObject.ReadNetworkPacket()
   at System.Data.SqlClient.TdsParserStateObject.ReadBuffer()
   at System.Data.SqlClient.TdsParserStateObject.ReadByte()
   at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior,SqlCommand cmdHandler,SqlDataReader dataStream,BulkCopySimpleResultSet bulkCopyHandler,TdsParserStateObject stateObj)
   at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds,RunBehavior runBehavior,String resetOptionsString)
   at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior,Boolean returnStream,Boolean async)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior,String method,DbAsyncResult result)
   at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(DbAsyncResult result,String methodName,Boolean sendToPipe)
   at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
   at System.Web.SessionState.SqlSessionStateStore.SetAndReleaseItemExclusive(HttpContext context,String id,SessionStateStoreData item,Object lockId,Boolean newItem)

或其他：

System.Data.SqlClient.SqlException: A transport-level error has occurred when sending the request to the server. (provider: TCP Provider,error: 0 - An existing connection was forcibly closed by the remote host.)
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception,Boolean breakConnection)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)
   at System.Data.SqlClient.TdsParserStateObject.WriteSni()
   at System.Data.SqlClient.TdsParserStateObject.WritePacket(Byte flushMode)
   at System.Data.SqlClient.TdsParserStateObject.ExecuteFlush()
   at System.Data.SqlClient.TdsParser.TdsExecuteRPC(_SqlRPC[] rpcArray,Int32 timeout,Boolean inSchema,SqlNotificationRequest notificationRequest,TdsParserStateObject stateObj,Boolean isCommandProc)
   at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior,Boolean newItem)

或另一个：

System.Data.SqlClient.SqlException: Timeout expired.  The timeout period elapsed prior to completion of the operation or the server is not responding.
   at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception,TdsParserStateObject stateObj)
   at System.Data.SqlClient.SqlDataReader.ConsumeMetaData()
   at System.Data.SqlClient.SqlDataReader.get_MetaData()
   at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds,DbAsyncResult result)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior,String method)
   at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior,String method)
   at System.Data.SqlClient.SqlCommand.ExecuteReader()
   at System.Web.SessionState.SqlSessionStateStore.DoGet(HttpContext context,Boolean getExclusive,Boolean& locked,TimeSpan& lockAge,Object& lockId,SessionStateActions& actionFlags)

这些错误每天发生几次，持续约1-2分钟，然后消失。有没有人遇到这样的问题？你可以建议我做什么，以进一步跟踪问题？对我来说，它看起来更像是网络问题，而不是应用程序。是否可以在SQL Server上的一些设置，无法处理这么多并发连接？任何建议将不胜感激。

更新：

我已经解决了这个问题，通过执行主要更新应用程序，以减少会话中存储的对象的数量和大小。