Is there a way to find out what is causing a (re)c...

# compose

[tad]

Is there a way to find out what is causing a (re)composition?

[Zach Klippenstein (he/him) [MOD]]

Not easily – why do you ask?

[tad]

Just trying to find out what's causing some scrolling lag when a particular composition comes into view

[Zach Klippenstein (he/him) [MOD]]

You could try using the regular android studio profiler to see if something’s doing a ton of work on the UI thread

[tad]

yeah, it's all in composition functions

[tad]

just trying to understand what state is changing to cause that

[Zach Klippenstein (he/him) [MOD]]

can you post any code?

[tad]

i'll need some time to distill it down, i'm doing some crazy stuff with nestedScroll to do a collapsing app bar

[tad]

Alright, it's not even that. LazyColumn is spending most of its time in LazyListState.onScroll , which spends like half a second calling remeasurement.forceRemeasure

[tad]

[Zach Klippenstein (he/him) [MOD]]

You should definitely file a bug, performance seems to be the primary focus of the compose team at this point and this investigation would probably be super helpful

[tad]

will do, thanks