Turbopack: Implement TraceRawVcs and NonLocalValue correctly for Effects#89133
Merged
Turbopack: Implement TraceRawVcs and NonLocalValue correctly for Effects#89133
Conversation
nextjs-bot
added
created-by: Turbopack team
Member
Author
This stack of pull requests is managed by Graphite. Learn more about stacking. |
Collaborator
Tests Passed |
Merging this PR will degrade performance by 3.83%
Performance Changes
Comparing 
Footnotes
|
Comment on lines
133
to
+144
| EffectState::NotStarted(_) => { | ||
| let EffectState::NotStarted(inner) = std::mem::replace( | ||
| &mut *guard, | ||
| EffectState::Started(Event::new(|| || "Effect".to_string())), | ||
| ) else { | ||
| unreachable!(); | ||
| let EffectState::NotStarted(effect) = | ||
| std::mem::replace(&mut *guard, EffectState::Invalid) | ||
| else { | ||
| unreachable!() | ||
| }; | ||
| State::NotStarted(inner) | ||
| let effect: Arc<dyn DynEffect> = Arc::from(effect); | ||
| *guard = EffectState::Started( | ||
| effect.clone(), | ||
| Event::new(|| || "Effect".to_string()), | ||
| ); | ||
| State::NotStarted(effect) |
Contributor
There was a problem hiding this comment.
can't we just capture effect in the match condition and then assign back? i guess that requires an additional clone on the effect Arc?
Member
Author
There was a problem hiding this comment.
I actually tried rewriting it that way, using a manual drop(guard) call. The appears to be some limitation of rustc's analysis here that cause it to think that the future is no longer Send because it thinks the mutex guard might get held across an await point (even though it isn't because of the drop(guard) call).
lukesandberg
approved these changes
Jan 28, 2026
Collaborator
Stats from current PR✅ No significant changes detected📊 All Metrics📖 Metrics GlossaryDev Server Metrics:
Build Metrics:
Change Thresholds:
⚡ Dev Server
📦 Dev Server (Webpack) (Legacy)📦 Dev Server (Webpack)
⚡ Production Builds
📦 Production Builds (Webpack) (Legacy)📦 Production Builds (Webpack)
📦 Bundle SizesBundle Sizes⚡ TurbopackClient Main Bundles
Server Middleware
Build DetailsBuild Manifests
📦 WebpackClient Main Bundles
Polyfills
Pages
Server Edge SSR
Middleware
Build DetailsBuild Manifests
Build Cache
🔄 Shared (bundler-independent)Runtimes
📎 Tarball URL |
bgw
force-pushed
the
bgw/effect-trace-raw-vcs
branch
2 times, most recently
from
c11b2a1 to
fd04529
Compare
bgw
force-pushed
the
bgw/effect-trace-raw-vcs
branch
from
fd04529 to
ebd1c55
Compare
bgw
force-pushed
the
bgw/effect-trait
branch
2 times, most recently
from
b7bb365 to
0a0ee57
Compare
bgw
force-pushed
the
bgw/effect-trace-raw-vcs
branch
from
ebd1c55 to
d6f9660
Compare
bgw
force-pushed
the
bgw/effect-trace-raw-vcs
branch
from
d6f9660 to
e1ace25
Compare
bgw
force-pushed
the
bgw/effect-trace-raw-vcs
branch
from
e1ace25 to
7ed4ec1
Compare
bgw
force-pushed
the
bgw/effect-trace-raw-vcs
branch
from
7ed4ec1 to
457fced
Compare
Member
Author
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
In subsequent PRs, I want to store a
ResolvedVc(specifically, aFileSystemPath, which contains aVc<Box<dyn FileSystem>>) inside of anEffect.To do this in a way that wouldn't break a hypothetical future tracing garbage collector, we must implement
TraceRawVcsonEffect.The previous PR changed the
Effecttype from a closure to a trait in order to enable this.