Excel freeze after stopping working macros - excel

Question

Let me explain.
I have a state similarity implementation in excel. One module, called a state, contains many public dictionaries at the top level.
I fill each dictionary with a huge number of object classes - mostly just data from sheets. Simple practice. The problem starts after the macro has worked normally, it leaves all these dictionaries in memory, in the task manager the Excel occupies from 2GB - this is also normal.
State Module - Standalone module
public Dict1 as Dictionary
public Dict2 as Dictionary
'Persists sheets data
public Dict3 as Dictionary
public Dict4 as Dictionary
'For persists renaming some objs
public Dict5 as Dictionary
public Dict6 as Dictionary
public Dict7 as Dictionary
Class Module - Data Interface Example - clsData
Public Name as string
Public Prop1 as string
Public Prop2 as Integer
Public Prop3 as Date
Public Prop4 as string
Public Value as double
The code below is just an example for stackoverflow. In my modules I am grabbing data from a sheet with the Range.CurrentRegion and iterate lbound to ubound.
Another data grabber
Function DataGrabberFromSheet(ByRef CurrentDict as Dict) as String
Dim i as long
Dim data as variant
Dim DataObj as clsData
set CurrentDict = New Dictionary <--- That's recreate dict obj and start clear old data for some how, but i do not need that anymore.
data = Sheet1.Range("A1:Q5000").Values
for i = 1 to 5000
set DataObj = new clsData
DataObj.Name = data(i, 1)
DataObj.Prop1 = data(i,2)
...
call CurrentDict.add(DataObj.Name, DataObj)
next
'For logging, it just an example:
If Success then
DataGrabberFromSheet = "Success"
else
DataGrabberFromSheet = "Bad"
endif
end Function
And so I decide in the debbuger to forcibly stop the program by pressing the stop button. At this point, Excel freezes for a long time, because I already have 50 or more of these dictionaries in the RAM, some of them have 200k elements each. Sometimes it takes about 300 seconds, and sometimes it instantly clears it somehow.
Old data erase by item, I think, but I do not need that data anymore. Can excel just skip that part of memory and just rewrite a new data.
How can I instantly redefine these dictionaries when the macro is rerun and not have to wait for that long cleanup? data is no longer needed at this point
Classic internet methods optimisations not solved that problem:
Application.Calculation = xlCalculationManual
Application.ScreenUpdating = False
...

Answer 1

I think this is a known issue with VBA - clearing a large number of objects takes a long time: regardless of whether they're stored in a dictionary, collection, or an array.
For example:
Dim arr() As clsData
Sub Tester()
Const NUM As Long = 120000
Dim i As Long, obj As clsData, t
t = Timer
Debug.Print "---------"
ReDim arr(1 To NUM)
Debug.Print "Reset", Timer - t
t = Timer
For i = 1 To NUM
Set obj = New clsData
obj.Prop1 = "Item" & i
obj.Prop2 = "Item" & i
obj.Prop3 = "Item" & i
obj.Prop4 = "Item" & i
Set arr(i) = obj
Next i
Debug.Print "Fill", Timer - t
End Sub
Where clsData is just:
Public Prop1
Public Prop2
Public Prop3
Public Prop4
Output from first run (after clicking "Stop" in VBE):
Reset 0
Fill 0.34375
Second run:
Reset 8.601563 <<<<<
Fill 0.3554688