Why there is a lag in forms?

[amirj700]

I'm building a large right to left form with complex fields (dropdowns, inlines, many-to-many, images, etc.). Unfortunately, I'm experiencing significant input lag on every click, which is worse on lower-resource computers. How can I diagnose and fix this performance issue?

[avixicu]

I ran into a similar issue recently, although in my case the slowdown happened when opening the Django admin change list (change_list.html). The page was extremely laggy because it was trying to load too many objects at once. What fixed it for me was explicitly limiting the number of items displayed per page in the model’s admin.py:

class MyModelAdmin(admin.ModelAdmin):
    list_per_page = 20

[amirj700]

I did the same but it has no effect, It seems that every time I click on a dorp down all of them refreshes.

[hypy13]

Hi amir
Can you send a screenshot
So i can understand better

[amirj700]

Hi Hossein, this is a screen shot of my page. @hypy13

تغییر محصول _ Amir Yadak Admin.pdf

[hypy13]

@amirj700
thanks for sharing
do u use "autocomplete_fields" for relation fields in ur form?

[amirj700]

Yes, some of them are auto complete, I like to use auto complete for many to many fields too, but they got messy and not scrolled.

[hypy13]

do you have this problem with default django admin
or it just raise with django-daisy?

[amirj700]

It's ok with django default admin. by changing to daisy it happens.

[hypy13]

sure ill check it ASAP
thanks for reporting @amirj700 bro

[hypy13]

Hey Amir,
I came back to this but couldn’t reproduce the issue on my side.

Could you please first make sure django-daisy is upgraded to the latest version (v2.0.7) and then do a hard refresh to clear cached assets?

If the issue still persists, I’d really appreciate it if you could contact me on Telegram (@hypyt) and share some of your relevant code (admin.py, models, etc.) so I can look into your specific setup and fix it properly.

[Jihad]

@hypy13 Hello! I'm noticing lag as well. Weird thing it's on chrome (or chromium browsers), but in Safari all works well; very snappy. On chrome, most interactions have noticeable lag.

Noticed in my testing:

1. it happens only when i'm on an index page with a table that have it's own scrollbar. (in chrome, scrollbar flickers with any interaction in page).

Tried to do a screen capture (top Vivaldi browser, bottom safari):
interaction lags

Another example with chrome dev tools > Paint Flashing [active].. showing whats elements needed to be repainted with every interaction (even hover)

[Jihad]

Hi @hypy13 - happy to share more examples, seemed the trigger is with components having many content that a scroll bar is showing.

[hypy13]

Hi, thanks for the detailed report and testing notes.

A few things to check on your side first:

Please verify whether the filter component contains a large number of values. A very large filter dataset can significantly impact rendering and interaction performance.

I also recommend adding django-debug-toolbar and analyzing the database queries on that page. Excessive queries or heavy query execution can easily cause UI lag, especially on index pages with tables.

If neither of these reveals an issue, then the next step would be for me to take a closer look at the frontend build and the DaisyUI component ecosystem being used

[Jihad]

@hypy13 Thanks for the reply!

Didn't think of checking it, but noticed lag happened on Pages with 5 Queries or 55 Queries, used the debug tool bar to show it:
screen capture

Am i missing anything else to debug?