Ich versuche, Aufgaben zu verwenden, aber ich wollte die Geschwindigkeitsdifferenz vergleichen, wenn Sie eine Standard-HttpWebRequest.BeginGetResponse verwenden.VB.Net BeginGetResponse viel schneller als die Verwendung von GetResponseAsync?
Von dem, was ich gefunden habe, ist es unter ~ 600 ms und BeginGetResponse
jedoch mit zu example.com 100 Anfragen vervollständigen zu senden, mit Await GetResponseAsync ist 5-fach, dass die Einnahme. Etwa 3000ms. In der Produktion ist mir das wichtig, wenn ich es hochskaliere. Mache ich etwas falsch, oder ist GetResponseAsync von Natur aus langsamer als BeginGetResponse?
Imports System.Net
Public Class Form1
Private sw As New Stopwatch
Private respCounter As Integer
Private iterations As Integer = 100
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
sw.Start()
For i = 1 To iterations
Dim req As HttpWebRequest = HttpWebRequest.Create("http://example.com")
Dim state As New RequestState
state.req = req
req.BeginGetResponse(AddressOf respCallback, state)
Next
End Sub
Private Sub respCallback(ar As IAsyncResult)
Dim state As RequestState = ar.AsyncState
state.resp = state.req.EndGetResponse(ar)
state.respStream = state.resp.GetResponseStream
state.respStream.BeginRead(state.buffer, 0, 1024, AddressOf readCallback, state)
End Sub
Private Sub readCallback(ar As IAsyncResult)
Dim state As RequestState = ar.AsyncState
Dim read As Integer = state.respStream.EndRead(ar)
If read > 0 Then
state.respBody += System.Text.ASCIIEncoding.ASCII.GetString(state.buffer, 0, read)
state.respStream.BeginRead(state.buffer, 0, 1024, AddressOf readCallback, state)
Else
state.Dispose()
respCounter += 1
If respCounter = iterations Then
respCounter = 0
sw.Stop()
Debug.WriteLine(sw.ElapsedMilliseconds)
sw.Reset()
End If
End If
End Sub
Private Async Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
sw.Start()
For i = 1 To iterations
Dim req As HttpWebRequest = HttpWebRequest.Create("http://example.com")
Using resp As WebResponse = Await req.GetResponseAsync
Using sr As New IO.StreamReader(resp.GetResponseStream)
Dim respBody As String = Await sr.ReadToEndAsync
End Using
End Using
respCounter += 1
If respCounter = iterations Then
respCounter = 0
sw.Stop()
Debug.WriteLine(sw.ElapsedMilliseconds)
sw.Reset()
End If
Next
MsgBox("Execution!")
End Sub
End Class
Public Class RequestState
Implements IDisposable
Public req As HttpWebRequest
Public resp As HttpWebResponse
Public respStream As IO.Stream
Public buffer(1024) As Byte
Public respBody As String
#Region "IDisposable Support"
Private disposedValue As Boolean ' To detect redundant calls
' IDisposable
Protected Overridable Sub Dispose(disposing As Boolean)
If Not disposedValue Then
If disposing Then
' TODO: dispose managed state (managed objects).
respStream.Close()
respStream.Dispose()
resp.Close()
End If
' TODO: free unmanaged resources (unmanaged objects) and override Finalize() below.
' TODO: set large fields to null.
End If
disposedValue = True
End Sub
' TODO: override Finalize() only if Dispose(disposing As Boolean) above has code to free unmanaged resources.
'Protected Overrides Sub Finalize()
' ' Do not change this code. Put cleanup code in Dispose(disposing As Boolean) above.
' Dispose(False)
' MyBase.Finalize()
'End Sub
' This code added by Visual Basic to correctly implement the disposable pattern.
Public Sub Dispose() Implements IDisposable.Dispose
' Do not change this code. Put cleanup code in Dispose(disposing As Boolean) above.
Dispose(True)
' TODO: uncomment the following line if Finalize() is overridden above.
' GC.SuppressFinalize(Me)
End Sub
#End Region
End Class
@x ... Hi, ich habe Anrufe zu EndGetResponseStream und EndGetResponse hinzugefügt, wenn die Anfragen abgeschlossen sind. Dann bekomme ich eine kryptische Ausnahme "Zusätzliche Information: Das IAsyncResult-Objekt wurde nicht von der entsprechenden asynchronen Methode für diese Klasse zurückgegeben." –
Ich mache nur einen Test mit GetResponse() und GetResponseAsync() und BeginGetResponse/EndGetResponse, sie zeigen die gleiche Zeit. –