Turbopack: Define Effect as a trait instead of a closure#89080
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Merging this PR will improve performance by 4.57%
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| /// has "settled". | ||
| /// | ||
| /// The effect can store [`ResolvedVc`]s (or any other `Vc` type), and this can return values | ||
| /// containing those [`ResolvedVc`]s, but it should not read or resolve the contents of a `Vc`. |
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is it allowed to execute a turbo-task?
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No. After reading through this code, it appears to be accurate to simply say something like:
> This function is executed outside of the turbo-tasks context, and therefore cannot read any Vcs or call any turbo-task functions.
I'll update the comment for clarity.
| util::SharedError, | ||
| }; | ||
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| const APPLY_EFFECTS_CONCURRENCY_LIMIT: usize = 1024; |
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if ~all effects are performing file IO.... which internally uses a semaphore should we bother with this extra limit?
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counterpoint is that we should align this with the file-io semaphore more? some small multiple of 4?
lukesandberg
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Jan 27, 2026
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This switches effects (special
Collectibles used to defer file writes) from using a closure representation to using a trait representation.This makes constructing effects a little more annoying, but it ensures that we'll be able to correctly implement
TraceRawVcson these in a subsequent PR.Changes to
turbo-tasks/src/effect.rswere done by hand, an LLM was used for updating the two callsites.