Time stamp in VB.Net

rachayita jaiswal

Hi, I have used time stamp in vb.net like this -

btnGenerateReport.Enabled = False
Dim sw As Stopwatch = Stopwatch.StartNew()

getreport() */ this is my function through ehich i am loading data

sw.Stop()
Dim ts As TimeSpan = sw.Elapsed
Label1.Text = ts.TotalMilliseconds.ToString() + " ms for summary report"

now i am getting time in milliseconds in my label

but each time milliseconds are different means first time it is "3392.2505 ms"
and same code when i run second time it is "3696.0097 ms".

it should be same....

Please tell me is there ant error in my code or why it is different each time???

Thanks

3 Replies

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Vulpes13y ago
You can calculate and show the average time elapsed as follows.

Each time the report is generated the average time is recalculated:

Protected Sub Page_Load(ByVal Sender As System.Object, ByVal e As System.EventArgs)
Handles Me.Load

If Not IsPostBack Then
Session.Item("Count") = 0
Session.Item("Total") = 0L
End If

End Sub

Protected Sub btnGenerateReport_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnGenerateReport.Click

btnGenerateReport.Enabled = false
Dim sw1 As Stopwatch = Stopwatch.StartNew()
getreport()
sw1.Stop()
Dim ems As Long = sw.ElapsedMilliseconds
Dim count As Integer = CInt(Session.Item("Count")) + 1
Dim total As Long = CLng(Session.Item("Total")) + ems
Dim average As Long = total / count;
Label1.Text = average.ToString() + " ms (average)"
Session.Item("Count") = count
Session.Item("Total") = total
btnGenerateReport.Enabled = true

End Sub
rachayita jaiswal13y ago
Hi, i am using local server only so how will i check performance in milliseconds because through this code time is keep changing..
Vulpes13y ago
When you perform a long running operation, it's very unlikely that the time taken will be exactly the same on any two occasions. Instead you'll get a range of times which you should average to get a mean time.

There are a number of reasons for this. For example, the thread on which the code is running may be interrupted by the operating system to run another thread or (in the case of .NET) the CLR may decide to perform a garbage collection in the middle of the operation.

Also, if you're obtaining data from an external server, the time taken for this to arrive will depend amongst other things on how busy the server is at the time of the request.