Reduce app startup latency by initializing the engine on a separate thread #166918

jason-simmons · 2025-04-10T15:47:39Z

If settings.merged_platform_ui_thread is set to kMergeAfterLaunch, then the engine will be started on the UI thread. After engine setup completes and the Dart isolate is loaded, the UI task runner will be merged into the platform thread and all future Dart execution will run on the platform thread.

This makes it possible for other work to run on the platform thread while the engine starts.

See #163064

jonahwilliams

LGTM!

chinmaygarde · 2025-04-10T19:57:46Z

engine/src/flutter/shell/common/switches.cc

+    } else if (merged_platform_ui == "disabled") {
+      settings.merged_platform_ui_thread =
+          Settings::MergedPlatformUIThread::kDisabled;
+    } else if (merged_platform_ui == "mergeAfterLaunch") {


Why a separate option? This should be a strict improvement on all platforms. So, perhaps we should always merge after launch when the "enabled". This avoids adding an additional flag.

This option requires support from the embedder which has not been implemented on all host platforms.

If kMergeAfterLaunch is selected, then the embedder needs to configure the thread host to create a UI thread (which will only be used during engine startup). Some embedders may only have a platform thread and thus will not support this mode.

chinmaygarde · 2025-04-10T20:01:43Z

Like we spoke about, my main concern remains the potential race that could happen between when the engine is setup, the isolate is launched, the merging happens, and when the main entrypoint is invoked. Not because the entrypoint cannot be invoked on a background thread, but the risk of any Dart invocation making an FFI call with the assumption that is on the main thread.

Maybe this race isn't happening but I am not able to convince myself that it cant. Perhaps add an FML_CHECK in DartIsolate::Run* or prove the same some other way?

In any case, beyond that primary concern (and perhaps the need for an additional flag), this LGTM!

jason-simmons · 2025-04-10T20:20:58Z

The Dart entrypoint is invoked on the UI thread during RuntimeController::LaunchRootIsolate prior to the thread merge.

To avoid that race, this relies on the current design of Dart where the entrypoint starts the isolate and queues execution of the app's actual main function.
(see https://dart.googlesource.com/sdk/+/refs/heads/main/sdk/lib/_internal/vm/lib/isolate_patch.dart#270)

The engine does the thread merge after LaunchRootIsolate returns. Any tasks that were queued to the UI task runner while starting the isolate will be moved to the platform thread. So the app's main will be executed entirely on the platform thread.

If Dart does not do this internally, then we would need to add our own mechanism to defer execution of user code until the thread merge is done.

…hread If settings.merged_platform_ui_thread is set to kMergeAfterLaunch, then the engine will be started on the UI thread. After engine setup completes and the Dart isolate is loaded, the UI task runner will be merged into the platform thread and all future Dart execution will run on the platform thread. This makes it possible for other work to run on the platform thread while the engine starts. This PR makes kMergeAfterLaunch the default mode in the Android embedder. See flutter#163064

jason-simmons · 2025-04-16T00:48:33Z

There is a deadlock when using MergedPlatformUIThread::kMergeAfterLaunch with the Shell::Spawn API (which creates a clone of the engine that shares the same task runners):

The app creates the root Shell instance on the platform thread.
The root Shell creates its engine and starts initializing it on the UI thread.
While the UI thread is starting the root engine, the platform thread can do other work.
- On the platform thread, the app calls Shell::Spawn to create a clone of the root shell.
Shell::Spawn calls Shell::CreateShellOnPlatformThread, which queues a task to the UI task runner to create the cloned engine.
The UI thread continues setting up the root engine and creates the root isolate. The UI thread then calls MessageLoopTaskQueues::Merge to merge the UI task queue into the platform queue so the isolate's tasks will run on the platform thread.
After the Merge the engine cloning task that was queued to the UI task runner will now be scheduled to run on the platform thread.
- But the platform thread is blocked in Shell::CreateShellOnPlatformThread waiting for that task to complete. So Shell::Spawn can not complete.

I experimented with a potential solution for this involving creation of a new UI task queue and task runner for each Shell instance:
https://github.com/jason-simmons/flutter/tree/merge_after_launch_sub_queue
Each shell's UI task runner can then be moved from the UI thread to the platform thread without affecting other clones of that shell. This works in the experiments that I tried, but the additional complexity and risk seem like a questionable tradeoff.

So I've updated this PR to disallow engine spawning if MergedPlatformUIThread::kMergeAfterLaunch is in use.

…separate thread (flutter/flutter#166918)

flutter/flutter@ecabb1a...3ed38e2 2025-04-18 [email protected] Update `led` docs (flutter/flutter#167380) 2025-04-18 [email protected] Throw an error if --local-engine-host is used without --local-engine (flutter/flutter#166948) 2025-04-18 [email protected] Add kotlin compatability to build file validation (flutter/flutter#167143) 2025-04-18 [email protected] Roll Skia from 844496884aa0 to 6c4595124690 (2 revisions) (flutter/flutter#167400) 2025-04-18 [email protected] Fix CarouselView crashes when initlal viewportDimension is 0.0 (flutter/flutter#167271) 2025-04-18 [email protected] Roll Dart SDK from b1eb743f97f5 to ab60afc99bcb (1 revision) (flutter/flutter#167396) 2025-04-18 [email protected] Add InputDecoration.visualDensity and InputDecorationTheme.visualDensity (flutter/flutter#166834) 2025-04-18 [email protected] Roll Skia from acc910544da7 to 844496884aa0 (1 revision) (flutter/flutter#167389) 2025-04-18 [email protected] Roll Skia from a409d685a711 to acc910544da7 (10 revisions) (flutter/flutter#167388) 2025-04-18 [email protected] Roll Dart SDK from 2bb85834e77e to b1eb743f97f5 (2 revisions) (flutter/flutter#167387) 2025-04-18 [email protected] Roll Fuchsia Linux SDK from m8Aln7fTF_8zy1V9N... to MwYckh5OvwwmIYLx0... (flutter/flutter#167385) 2025-04-17 [email protected] Roll Skia from cc2b57434651 to a409d685a711 (3 revisions) (flutter/flutter#167347) 2025-04-17 [email protected] Reduce app startup latency by initializing the engine on a separate thread (flutter/flutter#166918) 2025-04-17 [email protected] Roll Dart SDK from 992221a362ec to 2bb85834e77e (7 revisions) (flutter/flutter#167361) 2025-04-17 [email protected] Added docstring for FilterInput::GetSnapshot (flutter/flutter#167226) 2025-04-17 [email protected] adds Entity docstrings (flutter/flutter#167228) 2025-04-17 [email protected] fixed impeller golden content scale (flutter/flutter#167308) 2025-04-17 [email protected] Added docstring for FilterContents::RenderFilter (flutter/flutter#167227) 2025-04-17 [email protected] Feat: Add equality to NoDefaultCupertinoThemeData (flutter/flutter#166655) 2025-04-17 [email protected] Fix link to engine docs (flutter/flutter#167346) 2025-04-17 [email protected] [macOS] Enable merged platform and UI thread by default (flutter/flutter#166536) 2025-04-17 [email protected] [Windows] Enable merged platform and UI thread by default (flutter/flutter#163726) 2025-04-17 [email protected] Update `CHANGELOG.md` (flutter/flutter#167225) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

…parate thread (flutter#166918)" This reverts commit c53fdbd. See flutter#167418

…parate thread (#166918)" (#167427) This reverts commit c53fdbd. See #167418

…parate thread (flutter#166918)" This includes a fix for a race seen in EmbedderTest.PlatformThreadIsolatesWithCustomPlatformTaskRunner The implementaion of MergedPlatformUIThread::kMergeAfterLaunch required changing the interface of the TaskObserverAdd/TaskObserverRemove callbacks so that TaskObserverAdd returned the TaskQueueId where the observer was added. That TaskQueueId would later be given to TaskObserverRemove. The original implementation of this PR updated the embedder library's implementation of TaskObserverAdd to return TaskQueueId::kInvalid to signal that the observer was not added. However, this conflicted with the embedder's EmbedderTaskRunner, whose implementation of GetTaskQueueId returns TaskQueueId::kInvalid as a placeholder. This PR reverts the embedder's TaskObserverAdd/TaskObserverRemove to the original implementaion which adds the observer to the current thread's message loop and does not call GetTaskQueueId. See flutter#167418

…parate thread (flutter#166918)" This includes a fix for a race seen in EmbedderTest.PlatformThreadIsolatesWithCustomPlatformTaskRunner The implementaion of MergedPlatformUIThread::kMergeAfterLaunch required changing the interface of the TaskObserverAdd/TaskObserverRemove callbacks so that TaskObserverAdd returned the TaskQueueId where the observer was added. That TaskQueueId would later be given to TaskObserverRemove. The original implementation of this PR updated the embedder library's implementation of TaskObserverAdd to return TaskQueueId::kInvalid to signal that the observer was not added. However, this conflicted with the embedder's EmbedderTaskRunner, whose implementation of GetTaskQueueId returns TaskQueueId::kInvalid as a placeholder. This PR reverts the embedder's TaskObserverAdd/TaskObserverRemove to the original implementation which adds the observer to the current thread's message loop and does not call GetTaskQueueId. See flutter#167418

…parate thread (#166918)" (#167519) This includes a fix for a race seen in EmbedderTest.PlatformThreadIsolatesWithCustomPlatformTaskRunner The implementaion of MergedPlatformUIThread::kMergeAfterLaunch required changing the interface of the TaskObserverAdd/TaskObserverRemove callbacks so that TaskObserverAdd returned the TaskQueueId where the observer was added. That TaskQueueId would later be given to TaskObserverRemove. The original implementation of this PR updated the embedder library's implementation of TaskObserverAdd to return TaskQueueId::kInvalid to signal that the observer was not added. However, this conflicted with the embedder's EmbedderTaskRunner, whose implementation of GetTaskQueueId returns TaskQueueId::kInvalid as a placeholder. This PR reverts the embedder's TaskObserverAdd/TaskObserverRemove to the original implementation which adds the observer to the current thread's message loop and does not call GetTaskQueueId. See #167418

…167472) This relands #163726 without changes. The likely reason for flakiness was #166918 (#167418 (comment)).  *Replace this paragraph with a description of what this PR is changing or adding, and why. Consider including before/after screenshots.* *List which issues are fixed by this PR. You must list at least one issue. An issue is not required if the PR fixes something trivial like a typo.* *If you had to change anything in the [flutter/tests] repo, include a link to the migration guide as per the [breaking change policy].* ## Pre-launch Checklist - [x] I read the [Contributor Guide] and followed the process outlined there for submitting PRs. - [x] I read the [Tree Hygiene] wiki page, which explains my responsibilities. - [x] I read and followed the [Flutter Style Guide], including [Features we expect every widget to implement]. - [x] I signed the [CLA]. - [x] I listed at least one issue that this PR fixes in the description above. - [x] I updated/added relevant documentation (doc comments with `///`). - [x] I added new tests to check the change I am making, or this PR is [test-exempt]. - [x] I followed the [breaking change policy] and added [Data Driven Fixes] where supported. - [x] All existing and new tests are passing. If you need help, consider asking for advice on the #hackers-new channel on [Discord].  [Contributor Guide]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview [Tree Hygiene]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md [test-exempt]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#tests [Flutter Style Guide]: https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md [Features we expect every widget to implement]: https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md#features-we-expect-every-widget-to-implement [CLA]: https://cla.developers.google.com/ [flutter/tests]: https://github.com/flutter/tests [breaking change policy]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#handling-breaking-changes [Discord]: https://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md [Data Driven Fixes]: https://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md

flutter/flutter@ecabb1a...3ed38e2 2025-04-18 [email protected] Update `led` docs (flutter/flutter#167380) 2025-04-18 [email protected] Throw an error if --local-engine-host is used without --local-engine (flutter/flutter#166948) 2025-04-18 [email protected] Add kotlin compatability to build file validation (flutter/flutter#167143) 2025-04-18 [email protected] Roll Skia from 844496884aa0 to 6c4595124690 (2 revisions) (flutter/flutter#167400) 2025-04-18 [email protected] Fix CarouselView crashes when initlal viewportDimension is 0.0 (flutter/flutter#167271) 2025-04-18 [email protected] Roll Dart SDK from b1eb743f97f5 to ab60afc99bcb (1 revision) (flutter/flutter#167396) 2025-04-18 [email protected] Add InputDecoration.visualDensity and InputDecorationTheme.visualDensity (flutter/flutter#166834) 2025-04-18 [email protected] Roll Skia from acc910544da7 to 844496884aa0 (1 revision) (flutter/flutter#167389) 2025-04-18 [email protected] Roll Skia from a409d685a711 to acc910544da7 (10 revisions) (flutter/flutter#167388) 2025-04-18 [email protected] Roll Dart SDK from 2bb85834e77e to b1eb743f97f5 (2 revisions) (flutter/flutter#167387) 2025-04-18 [email protected] Roll Fuchsia Linux SDK from m8Aln7fTF_8zy1V9N... to MwYckh5OvwwmIYLx0... (flutter/flutter#167385) 2025-04-17 [email protected] Roll Skia from cc2b57434651 to a409d685a711 (3 revisions) (flutter/flutter#167347) 2025-04-17 [email protected] Reduce app startup latency by initializing the engine on a separate thread (flutter/flutter#166918) 2025-04-17 [email protected] Roll Dart SDK from 992221a362ec to 2bb85834e77e (7 revisions) (flutter/flutter#167361) 2025-04-17 [email protected] Added docstring for FilterInput::GetSnapshot (flutter/flutter#167226) 2025-04-17 [email protected] adds Entity docstrings (flutter/flutter#167228) 2025-04-17 [email protected] fixed impeller golden content scale (flutter/flutter#167308) 2025-04-17 [email protected] Added docstring for FilterContents::RenderFilter (flutter/flutter#167227) 2025-04-17 [email protected] Feat: Add equality to NoDefaultCupertinoThemeData (flutter/flutter#166655) 2025-04-17 [email protected] Fix link to engine docs (flutter/flutter#167346) 2025-04-17 [email protected] [macOS] Enable merged platform and UI thread by default (flutter/flutter#166536) 2025-04-17 [email protected] [Windows] Enable merged platform and UI thread by default (flutter/flutter#163726) 2025-04-17 [email protected] Update `CHANGELOG.md` (flutter/flutter#167225) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

…r#9114) flutter/flutter@ecabb1a...3ed38e2 2025-04-18 [email protected] Update `led` docs (flutter/flutter#167380) 2025-04-18 [email protected] Throw an error if --local-engine-host is used without --local-engine (flutter/flutter#166948) 2025-04-18 [email protected] Add kotlin compatability to build file validation (flutter/flutter#167143) 2025-04-18 [email protected] Roll Skia from 844496884aa0 to 6c4595124690 (2 revisions) (flutter/flutter#167400) 2025-04-18 [email protected] Fix CarouselView crashes when initlal viewportDimension is 0.0 (flutter/flutter#167271) 2025-04-18 [email protected] Roll Dart SDK from b1eb743f97f5 to ab60afc99bcb (1 revision) (flutter/flutter#167396) 2025-04-18 [email protected] Add InputDecoration.visualDensity and InputDecorationTheme.visualDensity (flutter/flutter#166834) 2025-04-18 [email protected] Roll Skia from acc910544da7 to 844496884aa0 (1 revision) (flutter/flutter#167389) 2025-04-18 [email protected] Roll Skia from a409d685a711 to acc910544da7 (10 revisions) (flutter/flutter#167388) 2025-04-18 [email protected] Roll Dart SDK from 2bb85834e77e to b1eb743f97f5 (2 revisions) (flutter/flutter#167387) 2025-04-18 [email protected] Roll Fuchsia Linux SDK from m8Aln7fTF_8zy1V9N... to MwYckh5OvwwmIYLx0... (flutter/flutter#167385) 2025-04-17 [email protected] Roll Skia from cc2b57434651 to a409d685a711 (3 revisions) (flutter/flutter#167347) 2025-04-17 [email protected] Reduce app startup latency by initializing the engine on a separate thread (flutter/flutter#166918) 2025-04-17 [email protected] Roll Dart SDK from 992221a362ec to 2bb85834e77e (7 revisions) (flutter/flutter#167361) 2025-04-17 [email protected] Added docstring for FilterInput::GetSnapshot (flutter/flutter#167226) 2025-04-17 [email protected] adds Entity docstrings (flutter/flutter#167228) 2025-04-17 [email protected] fixed impeller golden content scale (flutter/flutter#167308) 2025-04-17 [email protected] Added docstring for FilterContents::RenderFilter (flutter/flutter#167227) 2025-04-17 [email protected] Feat: Add equality to NoDefaultCupertinoThemeData (flutter/flutter#166655) 2025-04-17 [email protected] Fix link to engine docs (flutter/flutter#167346) 2025-04-17 [email protected] [macOS] Enable merged platform and UI thread by default (flutter/flutter#166536) 2025-04-17 [email protected] [Windows] Enable merged platform and UI thread by default (flutter/flutter#163726) 2025-04-17 [email protected] Update `CHANGELOG.md` (flutter/flutter#167225) If this roll has caused a breakage, revert this CL and stop the roller using the controls here: https://autoroll.skia.org/r/flutter-packages Please CC [email protected],[email protected] on the revert to ensure that a human is aware of the problem. To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose To report a problem with the AutoRoller itself, please file a bug: https://issues.skia.org/issues/new?component=1389291&template=1850622 Documentation for the AutoRoller is here: https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

…separate thread (flutter/flutter#166918)

…hread (flutter#166918) If settings.merged_platform_ui_thread is set to kMergeAfterLaunch, then the engine will be started on the UI thread. After engine setup completes and the Dart isolate is loaded, the UI task runner will be merged into the platform thread and all future Dart execution will run on the platform thread. This makes it possible for other work to run on the platform thread while the engine starts. See flutter#163064

…parate thread (flutter#166918)" (flutter#167427) This reverts commit c53fdbd. See flutter#167418

…parate thread (flutter#166918)" (flutter#167519) This includes a fix for a race seen in EmbedderTest.PlatformThreadIsolatesWithCustomPlatformTaskRunner The implementaion of MergedPlatformUIThread::kMergeAfterLaunch required changing the interface of the TaskObserverAdd/TaskObserverRemove callbacks so that TaskObserverAdd returned the TaskQueueId where the observer was added. That TaskQueueId would later be given to TaskObserverRemove. The original implementation of this PR updated the embedder library's implementation of TaskObserverAdd to return TaskQueueId::kInvalid to signal that the observer was not added. However, this conflicted with the embedder's EmbedderTaskRunner, whose implementation of GetTaskQueueId returns TaskQueueId::kInvalid as a placeholder. This PR reverts the embedder's TaskObserverAdd/TaskObserverRemove to the original implementation which adds the observer to the current thread's message loop and does not call GetTaskQueueId. See flutter#167418

…lutter#167472) This relands flutter#163726 without changes. The likely reason for flakiness was flutter#166918 (flutter#167418 (comment)).  *Replace this paragraph with a description of what this PR is changing or adding, and why. Consider including before/after screenshots.* *List which issues are fixed by this PR. You must list at least one issue. An issue is not required if the PR fixes something trivial like a typo.* *If you had to change anything in the [flutter/tests] repo, include a link to the migration guide as per the [breaking change policy].* ## Pre-launch Checklist - [x] I read the [Contributor Guide] and followed the process outlined there for submitting PRs. - [x] I read the [Tree Hygiene] wiki page, which explains my responsibilities. - [x] I read and followed the [Flutter Style Guide], including [Features we expect every widget to implement]. - [x] I signed the [CLA]. - [x] I listed at least one issue that this PR fixes in the description above. - [x] I updated/added relevant documentation (doc comments with `///`). - [x] I added new tests to check the change I am making, or this PR is [test-exempt]. - [x] I followed the [breaking change policy] and added [Data Driven Fixes] where supported. - [x] All existing and new tests are passing. If you need help, consider asking for advice on the #hackers-new channel on [Discord].  [Contributor Guide]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#overview [Tree Hygiene]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md [test-exempt]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#tests [Flutter Style Guide]: https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md [Features we expect every widget to implement]: https://github.com/flutter/flutter/blob/main/docs/contributing/Style-guide-for-Flutter-repo.md#features-we-expect-every-widget-to-implement [CLA]: https://cla.developers.google.com/ [flutter/tests]: https://github.com/flutter/tests [breaking change policy]: https://github.com/flutter/flutter/blob/main/docs/contributing/Tree-hygiene.md#handling-breaking-changes [Discord]: https://github.com/flutter/flutter/blob/main/docs/contributing/Chat.md [Data Driven Fixes]: https://github.com/flutter/flutter/blob/main/docs/contributing/Data-driven-Fixes.md

…separate thread (flutter/flutter#166918)

jason-simmons requested review from chinmaygarde and jonahwilliams April 10, 2025 15:47

jason-simmons requested a review from a team as a code owner April 10, 2025 15:47

github-actions bot added platform-android Android applications specifically platform-ios iOS applications specifically engine flutter/engine related. See also e: labels. team-ios Owned by iOS platform team labels Apr 10, 2025

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fix platform isolate task_observer_add callback

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jason-simmons force-pushed the bug_163064_merge_after_launch branch from 511e401 to f868f26 Compare April 15, 2025 18:32

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Roll Flutter from ecabb1a05212 to d20300874123 (20 revisions) flutter/packages#9111

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c53fdbdf2 Reduce app startup latency by initializing the engine on a …

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…separate thread (flutter/flutter#166918)

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c53fdbdf2 Reduce app startup latency by initializing the engine on a …

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…separate thread (flutter/flutter#166918)

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Roll Flutter from ecabb1a05212 to f20bc39cc005 (21 revisions) flutter/packages#9113

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engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Apr 18, 2025

c53fdbdf2 Reduce app startup latency by initializing the engine on a …

ba815a1

…separate thread (flutter/flutter#166918)

engine-flutter-autoroll mentioned this pull request Apr 18, 2025

Roll Flutter from ecabb1a05212 to 3ed38e24528a (23 revisions) flutter/packages#9114

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jason-simmons added a commit to jason-simmons/flutter that referenced this pull request Apr 18, 2025

Revert "Reduce app startup latency by initializing the engine on a se…

fedb564

…parate thread (flutter#166918)" This reverts commit c53fdbd. See flutter#167418

github-merge-queue bot pushed a commit that referenced this pull request Apr 19, 2025

Revert "Reduce app startup latency by initializing the engine on a se…

c586417

…parate thread (#166918)" (#167427) This reverts commit c53fdbd. See #167418

knopp mentioned this pull request Apr 21, 2025

Reland "[Windows] Enable merged platform and UI thread by default" #167472

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9 tasks

Piinks mentioned this pull request Apr 25, 2025

Flutter Notable Commits - 2025 #161460

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engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Aug 14, 2025

c53fdbdf2 Reduce app startup latency by initializing the engine on a …

daaf111

…separate thread (flutter/flutter#166918)

engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Aug 14, 2025

c53fdbdf2 Reduce app startup latency by initializing the engine on a …

6087732

…separate thread (flutter/flutter#166918)

romanejaquez pushed a commit to romanejaquez/flutter that referenced this pull request Aug 14, 2025

Revert "Reduce app startup latency by initializing the engine on a se…

0b47d19

…parate thread (flutter#166918)" (flutter#167427) This reverts commit c53fdbd. See flutter#167418

engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Aug 15, 2025

c53fdbdf2 Reduce app startup latency by initializing the engine on a …

533b822

…separate thread (flutter/flutter#166918)

engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Aug 15, 2025

c53fdbdf2 Reduce app startup latency by initializing the engine on a …

482eda3

…separate thread (flutter/flutter#166918)

engine-flutter-autoroll added a commit to engine-flutter-autoroll/packages that referenced this pull request Aug 16, 2025

c53fdbdf2 Reduce app startup latency by initializing the engine on a …

76db870

…separate thread (flutter/flutter#166918)

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