Hi,

 

I have been through the same thing; sadly to say the only way I solved it
was to change my database backend to mysql from mssql; My Delphi application
is currently running in 700 locations countrywide; so the database server is
hit with about 5 requests per second with over 14,000 simultaneous
connections and its all _smooth_.

 

Your case seems to be that you are connecting MSSQL clients via a wan
connection which I can guess is not as fast as a LAN connection; I don't
think the problem is the database backend or Delphi; its mysql. Not a
problem per-say; its just that MSSQL protocol over a network is "chatty" and
is quite heavy - not recommended to be used over the internet and other wan
networks where speed doesn't come easy.

 

You might find that the application is exceptionally slow and your ADO
connections are timing out over slow networks; I suggest you use a database
backend that is network friendly and has a very light protocol. Or build a 3
tier system where the clients run an application that communicate the bare
nessessities to an application server which translates into the commands
that will hit the database.

 

Hope this helps

 

PO Box 627 00502 Karen, 
Nairobi, Kenya.
Mobile: +254 722 996532
Fixed: +254 20 2050859
[EMAIL PROTECTED] 

  _____  

From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf
Of edsynergy
Sent: 30 April 2008 6:41 p
To: [email protected]
Subject: [delphi-en] Mssql Locking causes Delphi App to crash

 

I have just gone live with a delphi app which has mssql at the backend.
Under load testing it has been well behaved. It is now installed in a
large health organisation with users coming in over wan connections to
the sql server. For periods the system performs well and then it
crashes. All other users of the system also crash out as well. The
application will still launch and they can even log on but meaningful
work is not possible.

I have reviewed the code and cannot find an issue there. It would be
easy for me to blame the network/ old pc's ( and not doubt the clients
IT support could point a the software) but I rather get to the bottom
of it. The sql server is not on a dedicated server. It is one of
these new fangled virtual servers and I wonder if this is the issue.
After all it is only using the chunk of memory allocated to it by the
real server it is on. Would this impact on performance. Any views
would be much appreciated.

 



[Non-text portions of this message have been removed]

Reply via email to