We had a lot of grief troubleshooting a complex form so I'm posting this here in case someone else hits the same issue. There's not really a problem to solve, I have to document it for our project so it seemed useful to share.

Context:

• We were testing converting a complex report to see if we could use forms to streamline the approval process.
• Replicating the original report in forms resulted in a complex form with a large (19) number of lookups, as the original template used multiple separate dynamically generated tables.
• The total number of records wasn't especially high (~200).
• As the form was being built out performance quickly started to degrade, with initial page load times exceeding ten seconds at best or  25-30 at worst.
• The data load in was visible to the user as they had time to browse before the data loaded in.

• Laserfiche Forms Professional Version 11.0.2311.50585

• Modern Form Designer

Issue:

• Our troubleshooting included: increasing server resources, checking the underlying SQL performance. No significant improvements were made.
• To isolate the issue a new blank form was created, and the performance tested (averaged load times).
• After each testing iteration an additional lookup was added.
• Performance degraded roughly linearly with each lookup.

Observations:

• The lookups fire in an apparently random order (I don't think this matters, it just confounded out troubleshooting).
• The lookups run sequentially.
• The first lookup averages ~50ms
• Each subsequent lookup starts after the previous one completes and takes ~500ms.
• As a result lookup 1 takes ~50ms, lookup 3 takes ~1050ms, lookup 10 takes ~4550ms (I've attached a table out to 20 lookups).

Conclusion:

• These results are consistent enough that it doesn't look like a bug, just how the software handles data lookups.
• Forms with a large number of lookups are going to perform poorly. This will need to be accommodated in form / process design.

Approximate expected lookup load times: