Hello AIMMS Community,

My team has encountered an unusual issue on an app released on AIMMS Cloud. This issue is only seen when there are multiple users accessing the application. 

What is the error? When two users access the application, a “Busy” status is displayed every 3-5 seconds for both users and the app is frozen. This “Busy” displays even when the users are NOT changing anything and starts as soon as the second user’s app finishes starting up. The app has no issue with a single user. 

Clues to causes of the error? We have narrowed down the line of code that we introduced that causes this issue. “Empty sCoreDataIssues;”. sCoreDataIssues, a set, is assigned to a CDM category. This line is within a procedure “prCoreDataCheckForIssues”. This procedure is called in a number of “UponChange” procedures (called in webui::UponChangeProcedure). Our feeling is that some parameter or set is changing continuously, the upon change is being called, and the “prCoreDataCheckForIssues”, with a non-trivial time to run is being run over and over again. 

Any ideas to what may be causing this? Any suggestions on how to troubleshoot?

What is the best way to detect which upon change procedures are being called in an AIMMS cloud environment? (Note: because it is an issue with multiple users, we can only test in the cloud environment, not locally, so efficient testing is important). 

Any help is appreciated! This issue is really making us spin our wheels!

Thanks,

Melody