kayee
asked on
connector class
I have created a connector class in vb6 that will return me an reference to an atl object. The atl object is full of collections. When I spin through the collections using the connector class the performance seems to be 20 times worse than when connecting to the object directly. Can I speed up the performance when using the connector class?? The
connector class was modeled after the MSDN "Coffee" example! Here is how I call the connector and loop.
Private oC As scAtlObject
Private oConnector As clsConnector
Private Sub cmdConnect_Click()
Screen.MousePointer = vbHourglass
Set oConnector = New clsConnector
Set oC = oConnector.clsAtlConnector
Screen.MousePointer = vbDefault
End Sub
Private Sub cmdConnectDirect_Click()
Screen.MousePointer = vbHourglass
Set oC = new scAtlObject
oC.Load
Screen.MousePointer = vbDefault
End Sub
Private Sub cmdLoop_Click()
Dim oTemp as oT
Dim oTemp2 as oT2
Dim lStart as Long
Dim lEnd as Long
lStart = GetTickCount()
For Each oTemp in oC
For Each oTemp2 in oTemp
Next
Next
lEnd = GetTickCount()
MsgBox "Time(ms): " & lEnd - lStart
End Sub
connector class was modeled after the MSDN "Coffee" example! Here is how I call the connector and loop.
Private oC As scAtlObject
Private oConnector As clsConnector
Private Sub cmdConnect_Click()
Screen.MousePointer = vbHourglass
Set oConnector = New clsConnector
Set oC = oConnector.clsAtlConnector
Screen.MousePointer = vbDefault
End Sub
Private Sub cmdConnectDirect_Click()
Screen.MousePointer = vbHourglass
Set oC = new scAtlObject
oC.Load
Screen.MousePointer = vbDefault
End Sub
Private Sub cmdLoop_Click()
Dim oTemp as oT
Dim oTemp2 as oT2
Dim lStart as Long
Dim lEnd as Long
lStart = GetTickCount()
For Each oTemp in oC
For Each oTemp2 in oTemp
Next
Next
lEnd = GetTickCount()
MsgBox "Time(ms): " & lEnd - lStart
End Sub
ASKER
That is a good point, but If I use the existing for each logic the time to loop through my atl object when connected using the connector class is about 5 secs. I connect directly to my atl object and loop it takes about 20 milliseconds. Why is this so slow and what can I do to get the same performance as connecting directly?
Late binding?
Fastest acces is via early binding (vtable)
Fastest acces is via early binding (vtable)
ASKER
I use early binding, My atlobject and my activex exe connector are referenced in my vb project.
I don't see in your code accessing any property.
How are you accesing properties? How you do it when accessing object directly?
How are you accesing properties? How you do it when accessing object directly?
ASKER
When I connect directly, I create a instance of the atlobject by settin oC = new scAtlObject. Then I can call the method oC.Load which will load all of the collections.
Then I spin through the collections without accessing any properties to make sure the speed issue isn't in one of the properties.
Then I spin through the collections without accessing any properties to make sure the speed issue isn't in one of the properties.
Std com objects are slow, ATL is fast. Take any dummy ATL object and any COM object and you will see the same time differences. That is why you took the time to write it in ATL isn't it...
ASKER
I need some way to have multiple vb clients connect to the existing atl object with good performance. Is there some other way to do this?
ASKER CERTIFIED SOLUTION
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Firstly try taking a count before the loop and looping
ncount = oC.Count
for i = 1 to nCount
Do this for both loops. Then when using the individual object reference it with the item property.
eg.
ncount = oC.Count
for i = 1 to nCount
nInnerCount = OTemp.Count
for n = 1 to nInnerCount
set OTemp2 = oC(i).item(n)
oTemp2.DoSomething
next
next