Canvas App became too slow and difficult to work with this app because of it's slowness

[Anonymous]

Hi,

This is really important as this is a blocker for our current project's future enhancements. We are facing a potential problem of slowness of our app.

It is extremely slow when:

1. We copy screens, rename screens or copy few controls within a screen. It takes hell lot of time (almost half an hour and more).

2. User navigates to different screens.

Our App is a canvas app and has the following:

• 65 Screens
• Minimum 75 Controls in almost all screens
• Connected to Dataverse
• Uses Power Automate flows
• Has 120 Users
• We have 3 Per App Licenses ( for 3 environments) and 3 Per User Licenses for developers
• App is getting used from 8 Months in production

Please suggest proven and tried out ways to come out of this performance blocker. 

[PaulD1 · Accepted solution]

I suspect not what you want to hear, but an App with 65 screens is probably not a good fit with Power Apps. That said, to try to improve performance for you users, some things you can try...

Turn on Performance Monitor to see what data calls your App is making. Do you have a lot of cross-screen references? You should aim to make your screens not reference one another directly - instead of referencing a control on a different screen, try passing context variables between screens (as an argument in the Navigate command). The App Checker's Performance tab will show you where you have cross screen references.

I usually avoid Preview and Experimental features unless I really have to turn them on, but you may want to try turning on Delay Load and Keep recently visited screens in memory.

The goal here is to try to make your App only load screens and data when it absolutely has to.

As always, also try to ensure that all your formulas are delegable - again the App Checker Performance tab will help you identify where some non-delegable formulas exist, but it is no 100% reliable (e.g. will not warn when certain functions are combined in a non-delegable way) so keep watching the Performance Monitor, sorting by response size in descending order to try to determine the most expensive data calls and see what you can do about them.

Refresh is an absolute performance killer, so use it as infrequently as possible.

If you are using the standard CDM tables in Dataverse (like Account) try turning on Explicit Column Selection. The standard tables are badly modeled and have a crazy number of fields, the majority of which are probably not needed within the App and ECS will try to pull back only the relevant columns - note though that this is quite buggy and sometimes excludes columns you do need unless you write your formulas a specific way.

Some of the above may assist a bit in Studio, but Studio loads and analyzes the full App (whereas the player can load screens as required) so I'm not sure you are going to be able to improve Studio much - maybe try running on a more powerful PC?

[Anonymous]

Thanks a lot Paul for this help. Will the use of reusable components help as as per the best practices an app should not have more than 500 controls? Is a reusable component having multiple controls will be counted as one control in a screen of Canvas App?

[PaulD1]

I think that, as long as you isolate your screens from one another as much as possible (remove cross screen references) the 500 controls per App recommendation is one that I wouldn't worry about too much. Fixing delegation and removing Refresh (as much as possible) is likely to have more effect.

I use Galleries where I can to reduce the number of on-screen controls. As Components are still preview (and are not 'data-aware' AFAIK, so have limited use cases) I very rarely use them, but perhaps someone else can let us know if they have seen significant performance increases by using components.