Serious frontend's performance issue

[iphong (Phong Vu)]

I love the new Lovelace UI and I think you guys are doing a great job!!!

So after having hundreds of entities integrated with all sort of different kind of components. The generated lovelace begin to slow down significantly. I can hear my laptop fan revs up each time i open home assistant frontend.

And after some quick measurement and analytics, i found quite a few problems with some of the built-in lovelace card components.

Unused dom elements which doesn’t get cleanup. Look at the DOM Nodes and Event Listenner counts

And after a few clicks…

Redundant event listenners which werern’t removedstrong text during component life cycle

This is an example of using events without removing it when component unmounted

That’s just what i’ve observed so far! Will add more when i have time later on.

[iphong (Phong Vu)]

I’m not sure how is the ui are updated upon state change. But one little change should not cause the whole UI to redraw.

Screen Recording 2020-05-06 at 1.52.28 AM.mov (video)

[makai]

You should open an issue here:

home-assistant/frontend

[Lunkobelix]

I have some serious issues but not sure we have the same issues
I have a NUC I3/8FB/SSD and the automations are extremely fast, when I turn a light on the light turns on almost before the switch in Lovelace moves.

But navigating the interface is sluggish. Clicking the tabs in my simple dashboard stutters and the worst part is the Community/HACS page. When I click the tabs there it really stutters in a way that it shouldn’t on an I3. Do you also experience this?

[iphong (Phong Vu)]

“The clicking tabs to navigate” part it is. Its like the whole interface got reloaded again and again

[makai]

It seems that your performance issue was due to the way frontend icons were loaded. If this is it, it is solved in HA 0.110