Stable Thread Timing?

I have an application where I am using a System Thread to capture the screen
& Broadcast it to clients. Its "working", but the timing on the background
thread gets wildly erratic at times. Some times, its right away, some times
after 10 seconds. I have included the setup of the process and the outline
of the Call Back Method.

As posted, the callback method can be mildly erratic (only doing a
debug.writeline) I am guessing up to an 80% variance on the time it takes to
print the Debug messages with an average variance of about 15%-25%. It gets
even worse when I add in the real program logic with up to 300% variance on
the loop timing.

If I stop & start the thread, it always clears up the timing for a few
seconds. Then its back to its crazy erratic self.

I think it makes since to try this on another box, but I need to know if my
approach is a good one or if I am doing something wildly silly to start
with.

Thanks!
Setting up the Process:
MyBroadcast = New BroadcastClass(Broad_IPAddress,
Convert.ToInt16(Broad_Port), PollingDelay, BroadcastInterleaveDelay)

MyBroadcast.Background_Capture_Process = New
System.Threading.Thread(AddressOf MyBroadcast.Capture_Process)

MyBroadcast.My_Process_Enabled = True

MyBroadcast.Background_Capture_Process.Start()


Basics of the CallBack Method:
public shared My_Process_Enabled as boolean

Public Sub Capture_Process()

While My_Process_Enabled

Try

For MyLoop = 0 To 5

Next

Debug.WriteLine(" Done:" & TimeOfDay)

Application.DoEvents()

Debug.Flush()

Application.DoEvents()

Threading.Thread.Sleep(Convert.ToInt16(PollingSpee d))

Catch ex As Exception

Debug.WriteLine(ex.Message)

End Try

End While

End Sub

Using Thread.Sleep to control the time methods are executed is going to
get
you in trouble. Have you tried the System.Threading.Timer class? Also,
calling Application.DoEvents is *rarely* a good idea (although a thousand
and
one other people could explain why better than me).

Although the below provides code smaples in C#, it is becoming a standard
text on the ngs, and is very good:

http://www.yoda.arachsys.com/csharp/threads/

Hope this helps
Dan

"gregory_may" wrote:

I have an application where I am using a System Thread to capture the
screen
& Broadcast it to clients. Its "working", but the timing on the
background
thread gets wildly erratic at times. Some times, its right away, some
times
after 10 seconds. I have included the setup of the process and the
outline
of the Call Back Method.

As posted, the callback method can be mildly erratic (only doing a
debug.writeline) I am guessing up to an 80% variance on the time it takes
to
print the Debug messages with an average variance of about 15%-25%. It
gets
even worse when I add in the real program logic with up to 300% variance
on
the loop timing.

If I stop & start the thread, it always clears up the timing for a few
seconds. Then its back to its crazy erratic self.

I think it makes since to try this on another box, but I need to know if
my
approach is a good one or if I am doing something wildly silly to start
with.

Thanks!
Setting up the Process:
MyBroadcast = New BroadcastClass(Broad_IPAddress,
Convert.ToInt16(Broad_Port), PollingDelay, BroadcastInterleaveDelay)

MyBroadcast.Background_Capture_Process = New
System.Threading.Thread(AddressOf MyBroadcast.Capture_Process)

MyBroadcast.My_Process_Enabled = True

MyBroadcast.Background_Capture_Process.Start()


Basics of the CallBack Method:
public shared My_Process_Enabled as boolean

Public Sub Capture_Process()

While My_Process_Enabled

Try

For MyLoop = 0 To 5

Next

Debug.WriteLine(" Done:" & TimeOfDay)

Application.DoEvents()

Debug.Flush()

Application.DoEvents()

Threading.Thread.Sleep(Convert.ToInt16(PollingSpee d))

Catch ex As Exception

Debug.WriteLine(ex.Message)

End Try

End While

End Sub

I have an application where I am using a System Thread to capture the
screen & Broadcast it to clients. Its "working", but the timing on the
background thread gets wildly erratic at times. Some times, its right
away, some times after 10 seconds. I have included the setup of the
process and the outline of the Call Back Method.

As posted, the callback method can be mildly erratic (only doing a
debug.writeline) I am guessing up to an 80% variance on the time it takes
to print the Debug messages with an average variance of about 15%-25%. It
gets even worse when I add in the real program logic with up to 300%
variance on the loop timing.

If I stop & start the thread, it always clears up the timing for a few
seconds. Then its back to its crazy erratic self.

I think it makes since to try this on another box, but I need to know if
my approach is a good one or if I am doing something wildly silly to start
with.

Thanks!
Setting up the Process:
MyBroadcast = New BroadcastClass(Broad_IPAddress,
Convert.ToInt16(Broad_Port), PollingDelay, BroadcastInterleaveDelay)

MyBroadcast.Background_Capture_Process = New
System.Threading.Thread(AddressOf MyBroadcast.Capture_Process)

MyBroadcast.My_Process_Enabled = True

MyBroadcast.Background_Capture_Process.Start()


Basics of the CallBack Method:
public shared My_Process_Enabled as boolean

Public Sub Capture_Process()

While My_Process_Enabled

Try

For MyLoop = 0 To 5

Next

Debug.WriteLine(" Done:" & TimeOfDay)

Application.DoEvents()

Debug.Flush()

Application.DoEvents()

Threading.Thread.Sleep(Convert.ToInt16(PollingSpee d))

Catch ex As Exception

Debug.WriteLine(ex.Message)

End Try

End While

End Sub