我最近在开发计算机上遇到了与SQL Server的数据库连接问题。
System.InvalidOperationException:超时已过期。从池中获取连接之前经过的超时时间
如何监控连接池以弄清楚发生了什么?
更多信息:
我没有太多运气 - 我绝对不会泄漏连接。每个连接都在using
语句中。
当问题确实发生时,我打开了性能监视器窗口并且它没有显示接近池的限制(100) - 通常大约2-5个连接,所以我不认为池正在筋疲力尽,也许这是暂停。
但是,我已将ConnectionTimeout
设置为0 - 根据文档,这意味着它应该永远等待连接 - 但我没有看到这一点。
当它确实发生时,它发生得相当快 - 我在VS2010的调试器下运行 - 启动我的应用程序的新实例 - 它可能在启动的一两秒内发生 - 在启动应用程序时有发生了几个查询。我正在运行的实际SQL Server是SQL Express 2008.也许我应该尝试针对SQL Server 2008运行它,看看我是否看到任何不同的行为。
还有其他想法吗?
答案 0 :(得分:3)
查看与汇集相关的ADO.NET Performance Counters。
您描述的症状通常表明您正在泄漏连接。确保完成所有连接后,最好通过包裹using
声明。
答案 1 :(得分:1)
这里有一些代码来尝试池,然后故障转移到unpooled: 如果池出现问题,请使用此子站:
Public Sub OpenConn()
Dim sTempCNString As String = cn.ConnectionString
Try
' add a timeout to the cn string, following http://www.15seconds.com/issue/040830.htm
Dim iTimeOut As Integer = utils_Configuration.Get_ConfigInt("DBConnectTimeout", 0)
If (iTimeOut > 0 And Not cn.ConnectionString.ToLower.Contains("timeout")) Then
Diagnostics.Debug.Print("<><><><><><><> SHORT CONNECT WITH POOLING <><><><><><><><><> ")
cn.ConnectionString += ";Connect Timeout=" & iTimeOut.ToString() & ";"
End If
cn.Open()
IsOperational = True
Catch ex As Exception
Diagnostics.Debug.Print("ERROR IN OPENING, try no pool")
' see http://www.15seconds.com/issue/040830.htm
' turn off pooling
Diagnostics.Debug.Print("<><><><><><><> CONNECT WITHOUT POOLING <><><><><><><><><> ")
Dim sAddOn As String = ";Pooling=false;Connect Timeout=45;"
cn.ConnectionString = sTempCNString & sAddOn
cn.ConnectionString = cn.ConnectionString.Replace(";;", ";")
cn.Open()
End Try
End Sub
以下是监控池的一些代码:
Option Explicit On
Option Strict On
Imports System.Data.SqlClient
Imports System.Diagnostics
Imports System.Runtime.InteropServices
Imports Microsoft.VisualBasic
' ref: http://msdn2.microsoft.com/en-us/library/ms254503.aspx
Public Class utils_SqlPerfMon
Private PerfCounters(9) As PerformanceCounter
Private connection As SqlConnection
Public sConnectString As String = ""
Public sResult As String = ""
Public Sub New()
sConnectString = Tools.GetMainDBConn().ConnectionString
connection = New SqlConnection(sConnectString)
Exec()
End Sub
Public Sub New(ByVal strC As String)
sConnectString = strC
connection = New SqlConnection(sConnectString)
Exec()
End Sub
Public Sub Exec()
Me.SetUpPerformanceCounters()
Diagnostics.Debug.Print("Available Performance Counters:")
' Create the connections and display the results.
Me.CreateConnectionsAndDisplayResults()
End Sub
Private Sub CreateConnectionsAndDisplayResults()
' List the Performance counters.
WritePerformanceCounters()
Dim connection1 As SqlConnection = New SqlConnection( _
Me.sConnectString)
connection1.Open()
Diagnostics.Debug.Print("Opened the 1st Connection:")
WritePerformanceCounters()
connection1.Close()
Diagnostics.Debug.Print("Closed the 1st Connection:")
WritePerformanceCounters()
Return
End Sub
Private Enum ADO_Net_Performance_Counters
NumberOfActiveConnectionPools
NumberOfReclaimedConnections
HardConnectsPerSecond
HardDisconnectsPerSecond
NumberOfActiveConnectionPoolGroups
NumberOfInactiveConnectionPoolGroups
NumberOfInactiveConnectionPools
NumberOfNonPooledConnections
NumberOfPooledConnections
NumberOfStasisConnections
' The following performance counters are more expensive to track.
' Enable ConnectionPoolPerformanceCounterDetail in your config file.
' SoftConnectsPerSecond
' SoftDisconnectsPerSecond
' NumberOfActiveConnections
' NumberOfFreeConnections
End Enum
Private Sub SetUpPerformanceCounters()
connection.Close()
Me.PerfCounters(9) = New PerformanceCounter()
Dim instanceName As String = GetInstanceName()
Dim apc As Type = GetType(ADO_Net_Performance_Counters)
Dim i As Integer = 0
Dim s As String = ""
For Each s In [Enum].GetNames(apc)
Me.PerfCounters(i) = New PerformanceCounter()
Me.PerfCounters(i).CategoryName = ".NET Data Provider for SqlServer"
Me.PerfCounters(i).CounterName = s
Me.PerfCounters(i).InstanceName = instanceName
i = (i + 1)
Next
End Sub
Private Declare Function GetCurrentProcessId Lib "kernel32.dll" () As Integer
Private Function GetInstanceName() As String
'This works for Winforms apps.
'Dim instanceName As String = _
' System.Reflection.Assembly.GetEntryAssembly.GetName.Name
' Must replace special characters like (, ), #, /, \\
Dim instanceName As String = _
AppDomain.CurrentDomain.FriendlyName.ToString.Replace("(", "[") _
.Replace(")", "]").Replace("#", "_").Replace("/", "_").Replace("\\", "_")
'For ASP.NET applications your instanceName will be your CurrentDomain's
'FriendlyName. Replace the line above that sets the instanceName with this:
'instanceName = AppDomain.CurrentDomain.FriendlyName.ToString.Replace("(", "[") _
' .Replace(")", "]").Replace("#", "_").Replace("/", "_").Replace("\\", "_")
Dim pid As String = GetCurrentProcessId.ToString
instanceName = (instanceName + ("[" & (pid & "]")))
Diagnostics.Debug.Print("Instance Name: {0}", instanceName)
Diagnostics.Debug.Print("---------------------------")
Return instanceName
End Function
Private Sub WritePerformanceCounters()
Dim sdelim As String = vbCrLf ' "<br>"
Diagnostics.Debug.Print("---------------------------")
sResult += "---------------------------"
sResult += sdelim
Dim strTemp As String = ""
For Each p As PerformanceCounter In Me.PerfCounters
Try
Diagnostics.Debug.Print("{0} = {1}", p.CounterName, p.NextValue)
strTemp = p.CounterName & "=" & p.NextValue.ToString
Catch ex As Exception
strTemp = ""
End Try
sResult += strTemp
sResult += sdelim
Next
Diagnostics.Debug.Print("---------------------------")
sResult += "---------------------------"
sResult += sdelim
End Sub
Private Shared Function GetSqlConnectionStringDifferent() As String
' To avoid storing the connection string in your code,
' you can retrive it from a configuration file.
Return ("Initial Catalog=AdventureWorks;Data Source=.\SqlExpress;" & _
"User Id=LowPriv;Password=Data!05;")
End Function
End Class