Profiling Store.scope

[rcarver]

Huge caveat that I'm very much learning my way around profiling and TCA performance, but I noticed something surprising that I don't understand. Following is 550ms snapshot is from a pretty deeply nested view and store scope. Each time an action is sent through the scope it seems to spend a few Self Weight milliseconds, adding up to quite a bit of time just to get through all of the layers.

(BTW, this send is driven by a very frequent change of an audio timecode)

I believe it's this closure, which seems innocent enough: it's calling the scope transformation function and assigning it to a CurrentValueSubject. Or is it referring to the toLocalState closure?

swift-composable-architecture/Sources/ComposableArchitecture/Store.swift

Lines 338 to 343 in c41f8c4

	localStore.parentCancellable = self.state
	.dropFirst()
	.sink { [weak localStore] newValue in
	guard !isSending else { return }
	localStore?.state.value = toLocalState(newValue)
	}

Appreciate any insights into how to read this, if it's a problem, and how to solve it?