I've made thit list with compose. Are these perfor...

# compose

[manueldidonna]

I've made thit list with compose. Are these performances normal/expected?

Gist: https://gist.github.com/manueldidonna/1eef3017a4ff4e42865641482ea78817

[Leland Richardson [G]]

if you’re not doing anything other than scrolling then definitely not 🙂 If you have code to share it might be insightful for us to understand how you’re falling into a performance trap though

[manueldidonna]

Here is the code of the list https://gist.github.com/manueldidonna/1eef3017a4ff4e42865641482ea78817

[manueldidonna]

I am very curious to understand where the error lies

[romainguy]

It’s bizarre that so much time is spent issuing GPU commands

[romainguy]

It also looks like your list items have 2 backgrounds but I don’t understand was causes that in your code

[manueldidonna]

The entire layout is:

Column -> Surface -> Box -> Column -> List & Toolbar

Surface is the only one that draws a background. The first column has the main layout and a bottom navigation. Box is needed because I have a centered dialog screen that appears over the list

[Adam Powell]

while this isn't likely to be related to the performance question, try the Dialog composable, it creates a real dialog that behaves correctly with Android window management rather than a css-overlay style thing in the same window 🙂

[manueldidonna]

@Adam Powell Thanks, I will use it

[Leland Richardson [G]]

the code actually looks quite reasonable

[Leland Richardson [G]]

if i had to guess, i would say that image is acting up for some reason

[Leland Richardson [G]]

if you replace image with just a box of the same size, does it get way better?

[manueldidonna]

I've replaced the image with a box (same modifiers + a background). I've also used a proper Dialog composable but it doesn't affect the performance

[Leland Richardson [G]]

hmmm. those spikes don’t look great for such simple items. also gpu still taking longer than i’d expect

[Leland Richardson [G]]

wonder if we are drawing everything for every scroll?

[romainguy]

GPU isn’t high here

[manueldidonna]

Do you need some info? It's a debug build and I'm using a oneplus 6T

[romainguy]

What’s worrisome in the spikes is the green stuff

[romainguy]

that’s time spent in composition/measure/layout of Compose I assume

[romainguy]

(it’s basically time unaccounted for by the View system)

[romainguy]

The blue stuff is short but that’s bitmap uploads I think? as if something was being invalidated on every frame

[manueldidonna]

I've changed the adapter list with VerticalScroller + Column. There are 20 items. Performance seems to have improved 🙃

[Leland Richardson [G]]

sorry i thought red was gpu.

the green stuff is indeed worrisome. not sure if this time is adapterlist specific or more compose runtime + subcomposition. but it definitely shouldn’t be that expensive