How quickly "should" an app start?

[chlebowa]

An app built with the following data and modules (no filters) takes over a minute to start*, up to a minute and a half with module_specific = TRUE. The data is not particularly large but larger than the typical example data used in NEST packages. Pre-processing takes about 10 seconds. Since modules do not start until viewed, the (near) entirety of app startup taken up by teal itself. I suppose building the filter panel is one of the more time-consuming steps.

*) Measuring in a fresh session, from runnig the script that attaches all necessary packages, creates data and modules, and runs the app, until the moment the notification Data loaded - App fully started up appears on screen.

My question is: at what point should one consider the app taking too long to start? Is there a way to improve startup time?

10 datasets of ~30 MB in total and 13 modules

``` > data ✅︎ verified teal_data object [L] Parent: Bindings: • ADRS: [L] • ADEX: [L] • ADLB: [L] • ADAE: [L] • ADVS: [L] • ADSL: [L] • ADDV: [L] • ADCM: [L] • ADTTE: [L] • ADMH: [L] ``` ``` > sapply(ls(get_env(data)), \(x) dim(get_var(data, x))) ADAE ADCM ADDV ADEX ADLB ADMH ADRS ADSL ADTTE ADVS [1,] 1934 9216 11 773 8400 24399 1200 400 1600 8982 [2,] 69 95 62 74 103 75 49 39 50 75 ``` ``` > modules + root + Summary Tables + Data Table + Cross Table + Data Quality + Variable Browser + Missing Data + Outliers + Exploratory Plots + Count Barchart + Distribution Plot + Bivariate Plot + Scatter Plot + Scatterplot Matrix + Statistical Analyses + Regression + Response Plot + Principal Component Analysis ```

Tagging @gogonzo for visibility.

Code of Conduct

• [X] I agree to follow this project's Code of Conduct.

Contribution Guidelines

• [X] I agree to follow this project's Contribution Guidelines.

Security Policy

• [X] I agree to follow this project's Security Policy.

[chlebowa]

As evidenced by #1236, the creating the filter panel (FilteredData objects) is not the main culprit. Placing progress bars within filter panel ui or server functions did not yield additional information.

[gogonzo]

Tip to the assignee: Moment when the FilteredData is created for the module should be postponed in the same way as the data-filtering. Creation of FIlteredData should be conditional on:

• if the data has changed
• if the tab is active