DDE very slow with Excel 2002, repost

[Alexandre Nikolov]

I have a DDE server app that my clients use to import data
into Excel. After some of my clients upgraded to Excel
2002 & Windows XP I received numerous complaints about
sevier performans deterioration. For example a spreadsheet
with 150 DDE links used to update for 2-3 min with Excel
200 on Windows 2000. With Excel 2002 on Windows XP it take
15 to 20 min for the same spreadsheet !!! As they spent
lots of money for the upgrade, everithing was blamed on my
DDE server. I took some of their documents and made some
test with different versions of Windows, Excel and
OpenOffice 1.1. I observed the following:
On Windows XP:
1. With Excel 2002, after opening the document and
pressing the "Update" button, it takes a long time for
Excel to estabilish the DDE conversations. Once this is
done the updates go thruogh quickly (but still slower than
with Excel 2000)
2. With Excel 2002, after opening and pressing "Update",
if you switch to different app immideatly (so the Excel go
in the background) the initiation of DDE conversations gos
very fast and the data updates go faster. (but still
slower than with Excel 2000)
3. With Excel 2000 on both Windows 2000 & XP there is no
performance deterioration but on XP the updates are slower
than on 2000.
4. With OpenOffice useing the same documents like with MS
Excel, there is no performance deterioration on both
Windows 2000 & Windows XP, and the updates are faster than
with Excel 2000 or excel 2002.

I have the latest service packs installed for Wondows 2000
& Windows XP and the latest office service packs for
Office 2000 & Office XP, plus I installed all the updates
available for Excel 2002.

The same problem exists (according to my clients) with
Excel 2003 but I could not test it for myself as I do not
have the product.

Any sugestions ?
(e-mail address removed) - remove "_removethis_"
...

 

[Rob van Gelder]

I've had zero experience with DDE, so I can't help you there. I've dealt
with performance issues though.

Consider downloading monitoring tools from www.sysinternals.com like regmon,
filemon.
Specifically, try to identify what the difference is between switching to
another app and staying put. Although it probably wont identify the cause,
it will give you more clues as to where to look and tweak.

 

[pgerrish]

I heard 3 years ago that there was bugs with dde in operating sytems
greater than win2k ( I cannot remember the source of this ). The
impression I got when i was investigating this years ago was that DDE
capability would be included with programs like office but if there
where problems with it support would not be provided.

I would consider running your dde/excel app on a Nt4 machine with
Office 97. Figure out someway of triggering the update remotely and
then:

1.) write the updated information into a different excel spreadsheet
or
2.)do an update or insert to a SQL table and have your client excel ap
query the table.

 

[Guest]

You are 100% right about the DDE support. DDE is there but M$ does not fix bugs in it. (according to some articles I found in MSDN).

Meanwhile I abandoned DDE and implementedn solution useing COM and "RTD" (RealTimeData) function available in Excel 2002 and Excel 2003.