Excel Calculation is faster when visible than when Visible=False?

[JeffDotNet]

I have an application that makes use of excel Interop

I’m using Microsoft Excel Object Library 10

The application does the following:
• Loads an existing analysis spreadsheet
• Sets Calculation mode to Manual (to prepare for efficient data import)
• Clears the first worksheet (of previous input data)
• Imports the text file into the first worksheet
• Set Calculation mode back to automatic
• Parses a field cells on a results Worksheet

I noticed while testing the application that the cells appear to
(re)calculate much faster when the objApp.Visible = true. (Improving
calculation speed from several minutes to ~ 25 seconds) This doesn’t make
sense to me. My only thought is that excel is throwing up a prompt when my
spreadsheet is running invisibly and that this prompt eventually times out
allowing my method to eventually complete. I have already set DisplayAlerts
to false. The Analysis spreadsheet does not contain any macros so I wouldn’t
have expected this to be a privilege issue.

I prefer never to display the spreadsheet.

If anyone has any suggestions I would greatly appreciate them

Thanks,

Jeff
‘############################################
‘code that opens the spreadsheet
objApp = New Excel.Application
objApp.DisplayAlerts = False
objApp.UserControl = False
objApp.Visible = False ‘True

objBooks = objApp.Workbooks

‘objBooks.Open(FileName, UpdateLinks, ReadOnly, Format, Password,
WriteResPassword, IgnoreReadOnlyRecommended, Origin, Delimiter, Editable,
Notify, Converter, AddToMRU)

objBook = objBooks.Open(FilePath, 0, True, 5, String.Empty, String.Empty,
True, Excel.XlPlatform.xlWindows, ",", True, False, 0, True)
‘##########################################

‘public method that imports the text file
Public Sub importDataFromFile(ByVal FilePath As String)
Me.CalculationMode = Excel.XlCalculation.xlCalculationManual
'Import CSV file into data worksheet
importDataFromFile(FilePath, Sheets.Data)
Me.CalculationMode = Excel.XlCalculation.xlCalculationAutomatic
m_Calculating = False

End Sub

‘##############################################

‘ method that imports the text file into the WorkSheet
Protected Sub ImportDataFromFile(ByVal FilePath As String, ByVal
WorkSheetIndex As Integer)
Dim dataSheet As Excel._Worksheet =
CType(Me.objSheets(WorkSheetIndex), Excel._Worksheet) '
dataSheet.Activate()
ClearWorksheet(dataSheet) 'Must clear otherwise old data will just
be shifted to the right of new data


dataSheet.Range("A1").Select()
With dataSheet.QueryTables.Add(Connection:=String.Format("TEXT;{0}",
FilePath), _
Destination:=dataSheet.Range("A1"))
.Name = "Test_1"
.FieldNames = True
.RowNumbers = False
.FillAdjacentFormulas = False
.PreserveFormatting = True
.RefreshOnFileOpen = False
.AdjustColumnWidth = True
.RefreshPeriod = 0
.TextFilePromptOnRefresh = False
.TextFilePlatform = 437
.TextFileStartRow = 1
.TextFileParseType = Excel.XlTextParsingType.xlDelimited
.TextFileTextQualifier =
Excel.XlTextQualifier.xlTextQualifierDoubleQuote
.TextFileConsecutiveDelimiter = False
.TextFileTabDelimiter = False
.TextFileSemicolonDelimiter = False
.TextFileCommaDelimiter = True
.TextFileSpaceDelimiter = False
.TextFileTrailingMinusNumbers = True
.Refresh(BackgroundQuery:=False)
End With

End Sub

 

[Jialiang Ge [MSFT]]

Hello Jeff,

From your post, my understanding on this issue is: you wonder why the
ImportDataFromFile process is extremely slow only when
Excel.Application.Visible = false, and how to resolve it. If I'm off base,
please feel free to let me know.

First off, I suggest we identify which part of code in ImportDataFromFile
slows down the whole process when Application.Visible=false. Below are the
two possible approaches that can help us identify the location:

Approach 1. Debug the code lines. Step over each line of code in
ImportDataFromFile, and see which line hangs for a extremely long time. If
you are using Visual Studio, we can step over the code lines by pressing
F10.
Approach 2. Use a stop watch class to calculate each line's execution time:
http://www.codeproject.com/KB/vb/vbnetstopwatch.aspx. An
easier-to-implement stop watch is like:
Dim start As DateTime = DateTime.Now
'execute our code
Dim [end] As DateTime = DateTime.Now
Dim span As TimeSpan = [end] - start

I believe knowing which part of code slows down the process will help us
determine the underlying reason for the performance issue.

In addition, Jeff, I suggest you call Worksheet.EnableCalculation = False.
This will disable the recalculation of the sheet, and may accelerate the
import process.
http://msdn2.microsoft.com/en-us/library/aa214565(office.11).aspx
Does your target worksheet contain a lot of function(UDF) to be calculated?

Regards,
Jialiang Ge ([email protected], remove 'online.')
Microsoft Online Community Support

Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
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[Jialiang Ge [MSFT]]

Hello Jeff,

From your post, my understanding on this issue is: you wonder why the
ImportDataFromFile process is extremely slow only when
Excel.Application.Visible = false, and how to resolve it. If I'm off base,
please feel free to let me know.

First off, I suggest we identify which part of code in ImportDataFromFile
slows down the whole process when Application.Visible=false. Below are the
two possible approaches that can help us identify the location:

Approach 1. Debug the code lines. Step over each line of code in
ImportDataFromFile, and see which line hangs for a extremely long time. If
you are using Visual Studio, we can step over the code lines by pressing
F10.
Approach 2. Use a stop watch class to calculate each line's execution time:
http://www.codeproject.com/KB/vb/vbnetstopwatch.aspx. An
easier-to-implement stop watch is like:
Dim start As DateTime = DateTime.Now
'execute our code
Dim [end] As DateTime = DateTime.Now
Dim span As TimeSpan = [end] - start

I believe knowing which part of code slows down the process will help us
determine the underlying reason for the performance issue.

In addition, Jeff, I suggest you call Worksheet.EnableCalculation = False.
This will disable the recalculation of the sheet, and may accelerate the
import process.
http://msdn2.microsoft.com/en-us/library/aa214565(office.11).aspx

Does your target worksheet contain a lot of function(UDF) to be calculated?

If Visible is set to true, is there any dialog popped up on your side when
the ImportDataFromFile is processed?

Regards,
Jialiang Ge ([email protected], remove 'online.')
Microsoft Online Community Support

Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
feel free to let my manager know what you think of the level of service
provided. You can send feedback directly to my manager at:
(e-mail address removed).

==================================================
Get notification to my posts through email? Please refer to
http://msdn.microsoft.com/subscriptions/managednewsgroups/default.aspx#notif
ications.

Note: The MSDN Managed Newsgroup support offering is for non-urgent issues
where an initial response from the community or a Microsoft Support
Engineer within 1 business day is acceptable. Please note that each follow
up response may take approximately 2 business days as the support
professional working with you may need further investigation to reach the
most efficient resolution. The offering is not appropriate for situations
that require urgent, real-time or phone-based interactions or complex
project analysis and dump analysis issues. Issues of this nature are best
handled working with a dedicated Microsoft Support Engineer by contacting
Microsoft Customer Support Services (CSS) at
http://msdn.microsoft.com/subscriptions/support/default.aspx.
==================================================
This posting is provided "AS IS" with no warranties, and confers no rights.

 

[Jialiang Ge [MSFT]]

Hello Jeff,

Does the suggestion in my last reply help? Would you let me know the test
result based on debugging or clock watcher? Is there any dialog open when
excel is visible? If there is anything I can do for you, please let me
know.

Regards,
Jialiang Ge ([email protected], remove 'online.')
Microsoft Online Community Support

=================================================
Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
feel free to let my manager know what you think of the level of service
provided. You can send feedback directly to my manager at:
(e-mail address removed).

This posting is provided "AS IS" with no warranties, and confers no rights.
=================================================

 

[JeffDotNet]

Jialiang,

This was the first post from you on this thread. If you made a previous
post to this thread please submit it again.

The tests results were base on a release build of my application. I have a
visibility setting in my application configuration file that I edited between
tests. This visibility setting is used to set the visibility for the excel
instance.

No, there is not a dialog open when the excel instance is run as visible.

Please re-submit your previous suggests to the thread.

Thanks,

Jeff

 

[Jialiang Ge [MSFT]]

Hello Jeff,

There seems something wrong with newsgroup post synchronization in this
thread. I am sorry for it. Below is my initial response posted on March 25.
Hello Jeff,

From your post, my understanding on this issue is: you wonder why the
ImportDataFromFile process is extremely slow only when
Excel.Application.Visible = false, and how to resolve it. If I'm off base,
please feel free to let me know.

First off, I suggest we identify which part of code in ImportDataFromFile
slows down the whole process when Application.Visible=false. Below are the
two possible approaches that can help us identify the location:

Approach 1. Debug the code lines. Step over each line of code in
ImportDataFromFile, and see which line hangs for a extremely long time. If
you are using Visual Studio, we can step over the code lines by pressing
F10.
Approach 2. Use a stop watch class to calculate each line's execution time:
http://www.codeproject.com/KB/vb/vbnetstopwatch.aspx. An
easier-to-implement stop watch is like:
Dim start As DateTime = DateTime.Now
'execute our code
Dim [end] As DateTime = DateTime.Now
Dim span As TimeSpan = [end] - start

I think knowing which part of code slows down the process may help us
determine the underlying reason for the performance issue.

In addition, Jeff, I suggest you call Worksheet.EnableCalculation = False.
This will disable the recalculation of the sheet, and may accelerate the
import process.
http://msdn2.microsoft.com/en-us/library/aa214565(office.11).aspx

Does your target worksheet contain a lot of function(UDF) to be calculated?

If Visible is set to true, is there any dialog popped up on your side when
the ImportDataFromFile is processed?

Again, I am sorry for the inconveniences caused by the newsgroup system. I
have reported the system problem to the system owner through internal
channels. They will look into it and fix the problem.

Regards,
Jialiang Ge ([email protected], remove 'online.')
Microsoft Online Community Support

=================================================
Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
feel free to let my manager know what you think of the level of service
provided. You can send feedback directly to my manager at:
(e-mail address removed).

This posting is provided "AS IS" with no warranties, and confers no rights.
=================================================

 

[JeffDotNet]

Jialiang thanks for your suggestions. Unfortunately, I still haven’t solved
the problem.

Setting the calculation mode back to automatic is the CPU hog. I set
dataSheet.EnableCalculation = False but this didn't appear to have an impact
on speed. The import of the text file to the data page is relatively quick (
less than a second)


Public Sub importDataFromFile(ByVal FilePath As String)
Me.CalculationMode = Excel.XlCalculation.xlCalculationManual
'Import CSV file into data worksheet
importDataFromFile(FilePath, Sheets.Data)


Me.CalculationMode = Excel.XlCalculation.xlCalculationAutomatic
'(objApp.Calculation = Excel.XlCalculation.xlCalculationAutomatic)

m_Calculating = False

End Sub



The chart below show execution times for setting the spreadsheet back to
automatic calculation after the csv data import.

Run Column: Shows the consecutive runs. Here I'm reusing the same excel
instance, but loading new csv files. Note this execution time get
significantly faster each run even in manually importing the csv files into
the spread sheet.

Manual: This shows the same data import (edit text import) and calculation
done in excel without interop

Visible: Execution time when running with Excel instance visible

NotVisible: Execution time when running with Excel not visible
-------------Execution time in Seconds--------------
Run # Manual Visible NotVisible
1 50 59.7 301.4
2 9 47.3 67.8
3 ~0.5 0.37 0.3
4 ~0.5 0.28 0.3
----------------------------------------------------

I also noticed that when running with the excel instance visible but
minimized yielded the same
results as running with the instance set to not visible.

I tried calculating the pages individually but didn't see a real performance
improvement. Nearly all of the time is spent calculating one of the analysis
Worksheets. I noticed this worksheet uses Dmax, Dmin, and Daverage. Could
the searching in these functions cause strange execution times? (it gets
faster each time when using the spreadsheet manually )

Is there anyway clever way to get this waiting out of the way in advance?

My users will rarely be running more than one analysis a day. Therefore
they will always experience
a long wait. I really don't want to have to run with excel visible. I
think I should be able to get the cell calculation to execute invisibly at
least as fast as when the instance is executing visible.

Thanks,

Jeff

Hello Jeff,

There seems something wrong with newsgroup post synchronization in this
thread. I am sorry for it. Below is my initial response posted on March 25.
Hello Jeff,

From your post, my understanding on this issue is: you wonder why the
ImportDataFromFile process is extremely slow only when
Excel.Application.Visible = false, and how to resolve it. If I'm off base,
please feel free to let me know.

First off, I suggest we identify which part of code in ImportDataFromFile
slows down the whole process when Application.Visible=false. Below are the
two possible approaches that can help us identify the location:

Approach 1. Debug the code lines. Step over each line of code in
ImportDataFromFile, and see which line hangs for a extremely long time. If
you are using Visual Studio, we can step over the code lines by pressing
F10.
Approach 2. Use a stop watch class to calculate each line's execution time:
http://www.codeproject.com/KB/vb/vbnetstopwatch.aspx. An
easier-to-implement stop watch is like:
Dim start As DateTime = DateTime.Now
'execute our code
Dim [end] As DateTime = DateTime.Now
Dim span As TimeSpan = [end] - start

I think knowing which part of code slows down the process may help us
determine the underlying reason for the performance issue.

In addition, Jeff, I suggest you call Worksheet.EnableCalculation = False.
This will disable the recalculation of the sheet, and may accelerate the
import process.
http://msdn2.microsoft.com/en-us/library/aa214565(office.11).aspx

Does your target worksheet contain a lot of function(UDF) to be calculated?

If Visible is set to true, is there any dialog popped up on your side when
the ImportDataFromFile is processed?

Again, I am sorry for the inconveniences caused by the newsgroup system. I
have reported the system problem to the system owner through internal
channels. They will look into it and fix the problem.

Regards,
Jialiang Ge ([email protected], remove 'online.')
Microsoft Online Community Support

=================================================
Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
feel free to let my manager know what you think of the level of service
provided. You can send feedback directly to my manager at:
(e-mail address removed).

This posting is provided "AS IS" with no warranties, and confers no rights.
=================================================

 

[JeffDotNet]

Hello Jialiang,

There are a few differences that are worth noting.

• The data being imported is always CSV

In all of my tests I have been importing data from .CSV files. (there
wasn’t a delta because of the type of file.)

• When running excel manually (without my automation code) it takes ~50
seconds
The spreadsheet recalculates faster after successive data imports. This is
true even without my automation code. When I run it like an excel user it
takes 50 seconds to recalculate the cells the first time, then 10 seconds,
then it is nearly instantaneous. I’m wondering if it some kind of ambiguity
in the order of operations in the spreadsheet?

• When Excel. Application.Visible = True (using automation code) it takes
~60 seconds. With successive data imports into the same excel instance the
recalculation gets faster. By the 3rd data import recalculation is nearly
instantaneous.

• When Excel.Application.Visible = False or excel is visible but minimized
the recalculation after the first data import takes about 5 minutes. On the
second import it takes about ~70 seconds and on the third import it is nearly
instantaneous.

I’m wondering if there is some kind of race condition or order of
calculation issue that is impacted by the visibility of the excel instance.


I mentioned the long processing delays with the author of the spreadsheet
and a new very stripped down version was created. This version appears to
execute with the Excel.Application.Visible = False in a fraction of a second
on the first attempt.

I plan to start out with the original spreadsheet and strip it down with the
author until I see what is consuming all the CPU time.

Thanks,

Jeff

 

[Jialiang Ge [MSFT]]

Thanks, Jeff, for the confirmation. Based on my discussion with the
developers, it's very likely that the low performance is due to some
function use in the spreadsheet. We have not figured out the exact reason
without a reproduce. Is it possible for you to send the spreadsheet to me
if your company's policy allows? You may remove the critical/sensitive data
from the spreadsheet, and send it to my mailbox (e-mail address removed)

Thanks,
Jialiang Ge ([email protected], remove 'online.')
Microsoft Online Community Support

=================================================
Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
feel free to let my manager know what you think of the level of service
provided. You can send feedback directly to my manager at:
(e-mail address removed).

This posting is provided "AS IS" with no warranties, and confers no rights.
=================================================

 

[Jialiang Ge [MSFT]]

Hello Jeff,

The Office developers and I have researched the issue for several days,
but, I am sorry, we still cannot reproduce the issue and figure out what's
going wrong. A reproducible sample workbook from you will be very helpful
to us. My mailbox address can be found in my signature. In addition,
looking at the nature of this issue, it would require intensive
troubleshooting which would be done effectively with direct assistance from
a Microsoft Support Professional through Microsoft Product Support
Services. You can contact Microsoft Product Support directly to discuss
additional support options you may have available, by contacting us at
1-(800)936-5800 or by choosing one of the options listed at
http://support.microsoft.com/common/international.aspx?rdpath=fh;en-us;cntac
tms.

Regards,
Jialiang Ge ([email protected], remove 'online.')
Microsoft Online Community Support

=================================================
Delighting our customers is our #1 priority. We welcome your comments and
suggestions about how we can improve the support we provide to you. Please
feel free to let my manager know what you think of the level of service
provided. You can send feedback directly to my manager at:
(e-mail address removed).

This posting is provided "AS IS" with no warranties, and confers no rights.
=================================================