Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53035
# Changelog: [Internal]
This adds an ability to distinguish different trace recordings, based on mode
Reviewed By: sbuggay
Differential Revision: D79557790
fbshipit-source-id: cbb216df86fa1a4692e1b82c8a14a6049b5c45ec
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52960
# Changelog: [Internal]
We never call `stopTracing()` on a HostTarget, if the Agent was destroyed.
This could only happen if the session was destroyed. There could me multiple sessions, so we have to keep the source of truth for recording status in a session state.
Reviewed By: sbuggay
Differential Revision: D79435494
fbshipit-source-id: db72ffdf6856974e980afa78d59dec4bf45df289
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52961
# Changelog: [Internal]
Now that we've implemented all required serializers and TraceRecordedState has everything needed, we can migrate TracingAgent to use this new infra.
Reviewed By: sbuggay
Differential Revision: D79433497
fbshipit-source-id: 8c63f0faa50844786b7af8860c22fc006dd38414
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52964
# Changelog: [Internal]
Now TraceRecordingState should capture everything we need in order to display a trace on a timeline.
We just need to serialize it properly into collection of serialized Trace Events that would be sent via `Tracing.dataCollected` CDP events.
This is what this serializer is doing.
Reviewed By: sbuggay
Differential Revision: D79434655
fbshipit-source-id: 6b6858db23077eb7305781b9b0d98af8dedd68ca
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52967
# Changelog: [Internal]
We would need this to correctly serialize Runtime Sampling Profiles.
In case of recording the trace in the background, this might not be the value we would want to use, we would probably add another field or calculate it dynamically, depending on the tracing mode.
This is not the case for now, will be solved separately on top of the stack.
Reviewed By: sbuggay
Differential Revision: D79433502
fbshipit-source-id: 172ff19985d325585590794fb2523a24a6860221
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52963
# Changelog: [Internal]
We are deprecating previous `InstanceTarcingProfile` struct, but not removing yet, since this is still used and we will migrate in one of the diffs at the top of the stack.
The `InstanceTracingProfile` will consist only of Trace Events that were captured by PerformanceTracer, and will not store Runtime Sampling Profiles.
There are multiple reasons for this:
1. As of right now, Runtime Sampling Profiles are completely independant from Instance Profiles and do not require anythings from Instance as a Target to be represented on a timeline.
2. Although PerformanceTracer is a singleton, it should be this way. It captures events for something that can only be dispatched if there is an allocated React Instance, so in the future PerformanceTracer could become a data-member of InstanceTarget.
Reviewed By: sbuggay
Differential Revision: D79433498
fbshipit-source-id: 0fdf09517488bc5c6c8eb604aee66535cdc19ffb
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52968
# Changelog: [Internal]
Now that we've defined all actors and relationship between Agents, we can start recording profiles and store them on a recording state.
Reviewed By: sbuggay
Differential Revision: D79415396
fbshipit-source-id: 9639e59d619268d970b895da2e19dfd92c963a32
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52966
# Changelog: [Internal]
The current design for Tracing is flawed. Right now the logic is mostly scattered around CDP Agents, lifetime of which is tied to CDP session.
This diff introduces a new approach:
- The HostTarget will be the only Target that has public entrypoints to startTracing as part of the jsinspector backend.
- It will create and own TraceRecording that acts as a local session. We won't use wording session here, because it is already reserved for CDP case.
- Every Target will implement TracingAgent, lifetime of which will be limited by lifetime of either Target or TraceRecording.
- All these TracingAgent will have a reference to TraceRecordingState, which they can mutate
This approach unblocks:
- Recording traces without active CDP sessions, for example in a background.
- Recording full instance reloads and multiple profiles for Instances and Runtimes.
{F1980838032}
Reviewed By: sbuggay
Differential Revision: D79371359
fbshipit-source-id: 034e984fd7e977457bd41a980e5feb049db3339d
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53072
Changelog: [internal]
This creates a test to make sure there are no changes in React Native dramatically increasing memory usage in simple scenarios.
Reviewed By: rshest
Differential Revision: D79646758
fbshipit-source-id: d7a863468adabb75de7ceb123d96131564bd0959
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53071
Changelog: [internal]
The current API to take JS heap snapshots has some problems:
1. Ergonomics: it requires you to input the filepath where you want to store the snapshot. This isn't aligned with the behavior we have for JS traces where the output path is provided to you.
2. It doesn't work in optimized builds, as it requires a specific option in Hermes.
For 1), this replaces `Fantom.saveJSMemoryHeapSnapshot(filePath)` with `Fantom.takeJSMemoryHeapSnapshot()` that outputs the snapshot in a predefined path and prints it to the console.
For 2), this adds a new environment variable to force building Hermes with memory instrumentation (`FANTOM_ENABLE_JS_MEMORY_INSTRUMENTATION`). This is exposed as an option and not set by default because it has a performance overhead at runtime that we don't want to pay (especially in benchmarks).
This option only works when using Buck in development, because we want to generate this new binary type on demand when necessary, instead of making it part of the prebuilts we do before running tests in OSS and CI.
Reviewed By: lenaic
Differential Revision: D79642314
fbshipit-source-id: a2980616a495bd6dca29c0709a9581db6fb3f2cc
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53069
Changelog: [internal]
This changes the names of the JS traces from Fantom from using a unix timestamp in the file name to using the ISO date:
- From: `View-itest.js-1754406329686.cpuprofile`
- To: `View-itest.js-2025-08-05T15:05:29.686Z.cpuprofile`
Reviewed By: rshest
Differential Revision: D79646760
fbshipit-source-id: d8a654724c1abc2d3e285ee658c2d390d3241d82
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53091
# Changelog:
[Internal] -
This fixes some excessive printing from the benchmarking results, which happened even if there was no benchmarks ran.
Reviewed By: rubennorte
Differential Revision: D79719026
fbshipit-source-id: 0e75d97ae9c762cab25007bfab5ca8a6dc43e148
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53070
As per title, this change adds a warning if you call `pod install` with `RCT_NEW_ARCH_ENABLED` set to 0.
## Changelog:
[iOS][Added] - Add warning if RCT_NEW_ARCH_ENABLED is set to 0
Reviewed By: mdvacca
Differential Revision: D79655716
fbshipit-source-id: 516cc02f9b2dbddaae99c2d74bba249970641d1d
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53065
Instead of checking results from the previous day, allow to go back up to 7
days in the past to check for previous runs.
Changelog:
[Internal] [Changed] -
Reviewed By: cipolleschi
Differential Revision: D79568067
fbshipit-source-id: 5d6fac6a06b4e26e52de6fbf6187ec8f8e44e10e
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53066
This diff introduces the mechanism for us to store the result of nightly 3p
library integration on Firebase.
Having the result store, we can now query the result from the previous day and
report if the build is newly broken or recovered overnight.
Changelog:
[Internal] [Changed] -
Reviewed By: cipolleschi
Differential Revision: D79565536
fbshipit-source-id: ba839b2950462a7ca6186a163f93f062719304fb
Summary:
Pure cocoapods build with dyn frameworks was broken due to some missing dependencies with the new performance metrics of cdp
## Changelog:
[iOS][Fixed] - Fix pure cocoapods dynamic framework build
Pull Request resolved: https://github.com/facebook/react-native/pull/53075
Test Plan:
Tested locally in RNTester with
```
USE_FRAMEWORKS=dynamic bundle exec pod install
```
and then building from Xcode
Reviewed By: cortinico
Differential Revision: D79676186
Pulled By: cipolleschi
fbshipit-source-id: ae6b81138fcae66c67bedadb1e1ad9cd6c4b6c35
Summary:
Add filter to native animated allowlist.
## Changelog:
[GENERAL] [ADDED] - Allow filter usage with native animated driver.
<!-- Help reviewers and the release process by writing your own changelog entry.
Pick one each for the category and type tags:
For more details, see:
https://reactnative.dev/contributing/changelogs-in-pull-requests
Pull Request resolved: https://github.com/facebook/react-native/pull/52920
Test Plan: Tested on RNTester
Reviewed By: joevilches
Differential Revision: D79473929
Pulled By: lunaleaps
fbshipit-source-id: de6fcc0f18a1d656688dce513d2cf48a3c9d4f09
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53057
Changelog: [internal]
This adds a Fantom test to ensure that `setUpDefaultReactNativeEnvironment` doesn't read any feature flags. This prevents catching this as a runtime issue when the feature flag system complains that feature flags were accessed before being overridden, which always would happen if this module read any flags (as it runs before any product code that sets overrides).
Reviewed By: rshest
Differential Revision: D79639890
fbshipit-source-id: 6997609b7bf84947a6da53b58e68f9edd5654912
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53056
Changelog: [internal]
This exposes a utility method in `ReactNativeFeatureFlagsBase` to reset its internal state for testing purposes.
This is intentionally not exposed through `ReactNativeFeatureFlags` to avoid it being used at runtime.
Reviewed By: rshest
Differential Revision: D79639889
fbshipit-source-id: adfb6125d991994c9706d5952d309915fec8f815
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53026
This change prevents users from opting out of the New Architecure.
The change is non breaking with respect to building an app: all the functions are still there, even if they are unreachable, in case users will still call them explicitly.
We hardcoded all the values to enable the New Architecture, so there is no way to disable it.
This is a behavioral breaking change, though.
## Changelog:
[iOS][Removed] - Removed the opt-out from the New Architecture.
Reviewed By: cortinico
Differential Revision: D79090048
fbshipit-source-id: 9779bfedf50748d7adbef5f7ef038f469e30efc2
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53063
Update `IO.read` CDP method handler to validate the received `size` parameter.
This now accepts a max value of 10MB — adding a layer of safety in front of our current Android implementation, which fails at around ~15MB due to OkHttp limits.
Changelog: [Internal]
Reviewed By: vzaidman
Differential Revision: D79646155
fbshipit-source-id: c777802105dc31cdcc7e9e960c880e689540fddd
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53003
The new `onChildStartedNativeGesture` method accepts a nullable `ReactContext` value for the purpose of flushing active touch events. This change updates all callsites of that method to pass a `ReactContext`
Changelog: [Internal]
Reviewed By: mdvacca
Differential Revision: D79258727
fbshipit-source-id: 7b2950f514295dbe26822442c98079b8121cb3bf
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52925
# Changelog:
[Internal] -
This adds an extra "ranking" report when running Fantom benchmark vs different React Feature flag configurations.
It can be very useful when implementing some particular optimization, to streamline the before/after comparison wit this optimization enabled/disabled.
Reviewed By: andrewdacenko
Differential Revision: D79269601
fbshipit-source-id: f29e761e313d6857e5b3ac65faf2a387a84be9df
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53053
Changelog: [internal]
This adds a Fantom test to ensure that setting up the RN environment doesn't trigger the initialization for React components like View and Text, which should be lazy loaded when necessary.
Reviewed By: rshest
Differential Revision: D79636160
fbshipit-source-id: ef1fbd6cd531eb7082dce000ba74a5eed451e259
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53054
Changelog: [internal]
We eagerly require `AppRegistry` from environment initialization (`InitializeCore`) because it has some side-effects that are necessary for error reporting (see https://github.com/facebook/react-native/issues/34649 and https://github.com/facebook/react-native/pull/34650), but this change makes a lot of modules to be eagerly initialized.
This reduces that to avoid loading modules that not necessary for environment setup, which allows us to do things like setting up feature flags before modules like `View` and `Text` have been initialized.
Reviewed By: rshest
Differential Revision: D79636159
fbshipit-source-id: a3f1e0db3dd69112ceef3ea339167694e2457454
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52827
Changelog: [internal]
This adds **support for creating Hermes/JS sampling profiler traces in Fantom**, which is especially useful when running benchmarks.
Usage:
```
FANTOM_PROFILE_JS=1 yarn fantom Animated-benchmark
```
Output:
{F1980642216}
After this, the trace is fully symbolicated.
Can be opened directly in Google Chrome:
{F1980642229}
Or in the built-in viewer in VSCode:
{F1980642242} {F1980642240} {F1980642241}
When collapsing frames in the Flame Chart viewer in VSCode, we can quickly identify opportunities for optimizations.
This also supports multi-config environments. In that case, trace file names are created using a short representation of the configuration.
User guide for benchmarks in Fantom, including how to use this, will be done in a future diff.
NOTE: This still doesn't work in OSS because we don't support optimized mode there. In dev mode, there's a segmentation fault coming from this line: `hermesRuntime->sampledTraceToStreamInDevToolsFormat(fileStream)`
Reviewed By: sammy-SC
Differential Revision: D78905646
fbshipit-source-id: 382ddd5034db601309bd118cedde2fe0d57fde98
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53034
Changelog: [internal]
This is just a refactor to make sure that the constants we pass from the Fantom runner to its runtime are correct by using Flow to typecheck it.
Reviewed By: andrewdacenko
Differential Revision: D79565574
fbshipit-source-id: cbbab9cdec5ef5b3c82b929b8939c76c0ef41823
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52985
This class is essentially a wrapper of LayoutShadowNode with no extra logic added.
Let's remove it.
Changelog:
[Internal] [Changed] -
Reviewed By: alanleedev
Differential Revision: D79450688
fbshipit-source-id: 943e10e602cb9a5b77fca81e11d2333828b27813
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53025
It's now time to say goodbye to the Legacy Architecture :')
This change hardcodes the `newArchEnabled` property to true, and warns the users
if they're attempting to set it to false.
Changelog:
[Android] [Breaking] - Remove possibility to newArchEnabled=false in 0.82
Reviewed By: cipolleschi
Differential Revision: D78560296
fbshipit-source-id: ccfc45d2f7f21cc20e063cb901d76be3d41458d6
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53030
Changelog: [internal]
Removes `PerformanceEntryReporter::getCurrentTimeStamp` in favor of `HighResTimeStamp::now`, to make the source of truth more explicit.
Reviewed By: hoxyq
Differential Revision: D79560370
fbshipit-source-id: 0ccf2bf511781d3c47c6ddb4dd7f2061aab152b5
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53028
Changelog: [internal]
Now that we have mocking at a more fundamental level (`HighResTimeStamp` API) we can replace other timing mocks with that one.
This does it for `PerformanceEntryReporter` and the `NativePerformance` module.
Reviewed By: hoxyq
Differential Revision: D79557640
fbshipit-source-id: 86579b8bb586190ab7cc8721f30e60b3ef789798
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53018
Changelog: [internal]
This makes the test for LongTasks API use the new API for mocking timers in Fantom to make it deterministic, and re-enables it on Github.
Reviewed By: rshest
Differential Revision: D79554724
fbshipit-source-id: 984c66ecd7c20eb972ba1e6b19944532acb82246
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53019
Changelog: [internal]
This adds support for mocking `HighResTimeStamp` values in Fantom tests via a new `Fantom.installHighResTimeStampMock` function.
See new tests for more details on how it works.
Reviewed By: rshest
Differential Revision: D79554723
fbshipit-source-id: 8b0fb292948be118c7616fde1a8a84014af82de8
Ruslan Lesiutin
generatedunixname537391475639613
Rubén Norte
Ruslan Shestopalyuk
Vitali Zaidman
Riccardo Cipolleschi
Nicola Corti
nishan (o^▽^o)
Peter Abbondanzo
Sam Zhou
Zeya Peng
Andrew Datsenko
Alex Hunt
Devan Buggay