I have several external lists from BDC models that were created in Visual Studio and use LINQToSQL to pull data from SQL server. When you first access a list after an IIS reset has been performed or if you have not visited the list in several hours the list takes a while (1 to 3 minutes in production) for the list view and forms to load.
Our company uses the SPWakup script (http://spwakeup.codeplex.com/) and it does not help with external lists. I have actually gotten the source and modified it to include all external lists for our farm and this does help alot, and has solved part of my problem.
However, I still have a problem with idle times when the lists is not being used. Only a few users use the lists to update the backend SQL so the lag from inactivity is still a problem.
I've also tested building a simple external list using SPD and there is still a lag, although it does not appear to be as bad.
I'm wondering if I've missed something in creating my BDC model that would improve the performance or if anyone else has experienced a problem with slow initial performance and knows of a solution.
Note: as for # of records being the problem, that is not the problem. I have limited my queries to return 5 records and still experience the same initial lag if I wait several hours between visiting the list.
Thanks for any insight or links to related information that will help me resolve this problem.
wm5
