Log Suspended startViewTransition Phase #34511
Merged
+90
−1
Conversation
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
sebmarkbage
requested review from
rickhanlonii,
jackpope,
eps1lon and
hoxyq
github-actions
bot
added
the
React Core Team
sebmarkbage
force-pushed
the
vtperformanceblocked
branch
from
c243ba5 to
a1c633b
Compare
|
Comparing: 84af908...a954a6d Critical size changesIncludes critical production bundles, as well as any change greater than 2%:
Significant size changesIncludes any change greater than 0.2%: Expand to show
|
sebmarkbage
force-pushed
the
vtperformanceblocked
branch
from
a1c633b to
a954a6d
Compare
eps1lon
approved these changes
Sep 18, 2025
github-actions bot
pushed a commit
that referenced
this pull request
Sep 18, 2025
Stacked on #34510. The "Commit" phase for a View Transition starts before the snapshot phase (before mutation) and then stretches into the async gap of `startViewTransition`, encompasses the mutation phase inside of its update callback and finally the layout phase. However, between the mutation phase and the layout phase we may suspend the start of the view transition on fonts and/or images. In that case we now split the Commit phase into first one before we suspend and then we log "Waiting for Images and/or Fonts" and then another Commit phase around the layout effects. <img width="897" height="119" alt="Screenshot 2025-09-16 at 11 37 26 PM" src="https://github.com/user-attachments/assets/0fe21388-bb48-4456-a594-62227d12d9b7" /> DiffTrain build for [ad578aa](ad578aa)
github-actions bot
pushed a commit
that referenced
this pull request
Sep 18, 2025
Stacked on #34510. The "Commit" phase for a View Transition starts before the snapshot phase (before mutation) and then stretches into the async gap of `startViewTransition`, encompasses the mutation phase inside of its update callback and finally the layout phase. However, between the mutation phase and the layout phase we may suspend the start of the view transition on fonts and/or images. In that case we now split the Commit phase into first one before we suspend and then we log "Waiting for Images and/or Fonts" and then another Commit phase around the layout effects. <img width="897" height="119" alt="Screenshot 2025-09-16 at 11 37 26 PM" src="https://github.com/user-attachments/assets/0fe21388-bb48-4456-a594-62227d12d9b7" /> DiffTrain build for [ad578aa](ad578aa)
This was referenced Sep 19, 2025
unstubbable
pushed a commit
to vercel/next.js
that referenced
this pull request
Sep 19, 2025
[diff facebook/react@84af9085...d415fd3e](facebook/react@84af908...d415fd3) <details> <summary>React upstream changes</summary> - facebook/react#34536 - facebook/react#34534 - facebook/react#34531 - facebook/react#34499 - facebook/react#34523 - facebook/react#34511 - facebook/react#34516 - facebook/react#34455 - facebook/react#34488 - facebook/react#34521 </details>
sebmarkbage
added a commit
that referenced
this pull request
Sep 20, 2025
Stacked on #34511. We currently log all Suspended Commit as "Suspended on Images or CSS" but it can really be other reasons too now. Like waiting on the previous View Transition. This allows the host config configure this reason. Now when one animation starts before another one finishes we log that as "Waiting for the previous Animation". <img width="592" height="257" alt="Screenshot 2025-09-17 at 11 53 45 PM" src="https://github.com/user-attachments/assets/817af8b5-37ae-46d8-bfd1-cd3fc637f3f3" />
github-actions bot
pushed a commit
that referenced
this pull request
Sep 20, 2025
Stacked on #34511. We currently log all Suspended Commit as "Suspended on Images or CSS" but it can really be other reasons too now. Like waiting on the previous View Transition. This allows the host config configure this reason. Now when one animation starts before another one finishes we log that as "Waiting for the previous Animation". <img width="592" height="257" alt="Screenshot 2025-09-17 at 11 53 45 PM" src="https://github.com/user-attachments/assets/817af8b5-37ae-46d8-bfd1-cd3fc637f3f3" /> DiffTrain build for [b204edd](b204edd)
github-actions bot
pushed a commit
that referenced
this pull request
Sep 20, 2025
Stacked on #34511. We currently log all Suspended Commit as "Suspended on Images or CSS" but it can really be other reasons too now. Like waiting on the previous View Transition. This allows the host config configure this reason. Now when one animation starts before another one finishes we log that as "Waiting for the previous Animation". <img width="592" height="257" alt="Screenshot 2025-09-17 at 11 53 45 PM" src="https://github.com/user-attachments/assets/817af8b5-37ae-46d8-bfd1-cd3fc637f3f3" /> DiffTrain build for [b204edd](b204edd)
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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.
Stacked on #34510.
The "Commit" phase for a View Transition starts before the snapshot phase (before mutation) and then stretches into the async gap of
startViewTransition, encompasses the mutation phase inside of its update callback and finally the layout phase.However, between the mutation phase and the layout phase we may suspend the start of the view transition on fonts and/or images. In that case we now split the Commit phase into first one before we suspend and then we log "Waiting for Images and/or Fonts" and then another Commit phase around the layout effects.