Remove JND delay for non-transition updates #26597
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Updates that are marked as part of a transition are allowed to block a render from committing. Generally, other updates cannot — however, there's one exception that's leftover from a previous iteration of our Suspense architecture. If an update is not the result of a known urgent event type — known as "Default" updates — then we allow it to suspend briefly, as long as the delay is short enough that the user won't notice. We refer to this delay as a "Just Noticable Difference" (JND) delay. To illustrate, if the user has already waited 400ms for an update to be reflected on the screen, the theory is that they won't notice if you wait an additional 100ms. So React can suspend for a bit longer in case more data comes in. The longer the user has already waited, the longer the JND. While we still believe this theory is sound from a UX perspective, we no longer think the implementation complexity is worth it. The main thing that's changed is how we handle Default updates. We used to render Default updates concurrently (i.e. they were time sliced, and were scheduled with postTask), but now they are blocking. Soon, they will also be scheduled with rAF, too, which means by the end of the next rAF, they will have either finished rendering or the main thread will be blocked until they do. There are various motivations for this but part of the rationale is that anything that can be made non-blocking should be marked as a Transition, anyway, so it's not worth adding implementation complexity to Default. This commit removes the JND delay for Default updates. They will now commit immediately once the render phase is complete, even if a component suspends.
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Updates that are marked as part of a transition are allowed to block a render from committing. Generally, other updates cannot — however, there's one exception that's leftover from a previous iteration of our Suspense architecture. If an update is not the result of a known urgent event type — known as "Default" updates — then we allow it to suspend briefly, as long as the delay is short enough that the user won't notice. We refer to this delay as a "Just Noticable Difference" (JND) delay. To illustrate, if the user has already waited 400ms for an update to be reflected on the screen, the theory is that they won't notice if you wait an additional 100ms. So React can suspend for a bit longer in case more data comes in. The longer the user has already waited, the longer the JND. While we still believe this theory is sound from a UX perspective, we no longer think the implementation complexity is worth it. The main thing that's changed is how we handle Default updates. We used to render Default updates concurrently (i.e. they were time sliced, and were scheduled with postTask), but now they are blocking. Soon, they will also be scheduled with rAF, too, which means by the end of the next rAF, they will have either finished rendering or the main thread will be blocked until they do. There are various motivations for this but part of the rationale is that anything that can be made non-blocking should be marked as a Transition, anyway, so it's not worth adding implementation complexity to Default. This commit removes the JND delay for Default updates. They will now commit immediately once the render phase is complete, even if a component suspends. DiffTrain build for [0b931f9](0b931f9)
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`eventTimes` represents the timestamp of the event that scheduled an update. The last remaining use for this field was the JND delay that was removed in facebook#26597. We can now delete it, and all the code we had for tracking it.
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`eventTimes` represents the timestamp of the event that scheduled an update. The last remaining use for this field was the JND delay that was removed in facebook#26597. We can now delete it, and all the code we had for tracking it.
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Apr 13, 2023
Summary: This sync includes the following changes: - **[58742c21b](facebook/react@58742c21b )**: Delete unused `eventTimes` Fiber field ([#26599](facebook/react#26599)) //<Andrew Clark>// - **[0b931f90e](facebook/react@0b931f90e )**: Remove JND delay for non-transition updates ([#26597](facebook/react#26597)) //<Andrew Clark>// - **[ac43bf687](facebook/react@ac43bf687 )**: Move validation of text nesting into ReactDOMComponent ([#26594](facebook/react#26594)) //<Sebastian Markbåge>// - **[ca41adb8c](facebook/react@ca41adb8c )**: Diff properties in the commit phase instead of generating an update payload ([#26583](facebook/react#26583)) //<Sebastian Markbåge>// - **[dd0619b2e](facebook/react@dd0619b2e )**: rename $$$hostConfig to $$$config ([#26593](facebook/react#26593)) //<Josh Story>// - **[b55d31955](facebook/react@b55d31955 )**: Rename HostConfig files to FiberConfig to clarify they are configs fo… ([#26592](facebook/react#26592)) //<Josh Story>// - **[ffb8eaca5](facebook/react@ffb8eaca5 )**: Rename ReactServerFormatConfig to ReactFizzConfig ([#26591](facebook/react#26591)) //<Josh Story>// - **[f4f873f62](facebook/react@f4f873f62 )**: Implements wiring for Flight to have it's own "HostConfig" ([#26590](facebook/react#26590)) //<Josh Story>// - **[44db16afc](facebook/react@44db16afc )**: Normalize ReactFlightServerConfig and related files ([#26589](facebook/react#26589)) //<Josh Story>// - **[fec97ecbc](facebook/react@fec97ecbc )**: act: Move didScheduleLegacyUpdate to ensureRootIsScheduled ([#26552](facebook/react#26552)) //<Andrew Clark>// - **[9a9da7721](facebook/react@9a9da7721 )**: Don't update textarea defaultValue and input checked unnecessarily ([#26580](facebook/react#26580)) //<Sebastian Markbåge>// - **[e5146cb52](facebook/react@e5146cb52 )**: Refactor some controlled component stuff ([#26573](facebook/react#26573)) //<Sebastian Markbåge>// - **[657698e48](facebook/react@657698e48 )**: [Tests] `waitForThrow` should diff strings ([#26568](facebook/react#26568)) //<Josh Story>// - **[85bb7b685](facebook/react@85bb7b685 )**: Fix: Move `destroy` field to shared instance object ([#26561](facebook/react#26561)) //<Andrew Clark>// - **[9cfba0f6e](facebook/react@9cfba0f6e )**: Clean up discrete event replaying ([#26558](facebook/react#26558)) //<Sebastian Markbåge>// - **[790ebc962](facebook/react@790ebc962 )**: Remove no-fallthrough lint suppressions ([#26553](facebook/react#26553)) //<Sophie Alpert>// - **[c15579631](facebook/react@c15579631 )**: Put common aliases in Map/Set instead of switch over strings ([#26551](facebook/react#26551)) //<Sebastian Markbåge>// - **[d5fd60f7e](facebook/react@d5fd60f7e )**: Remove findInstanceBlockingEvent unused parameters ([#26534](facebook/react#26534)) //<Mohammad Ghorbani>// - **[eeabb7312](facebook/react@eeabb7312 )**: Refactor DOM Bindings Completely Off of DOMProperty Meta Programming ([#26546](facebook/react#26546)) //<Sebastian Markbåge>// - **[da94e8b24](facebook/react@da94e8b24 )**: Revert "Cleanup enableSyncDefaultUpdate flag ([#26236](facebook/react#26236))" ([#26528](facebook/react#26528)) //<Jan Kassens>// - **[0700dd50b](facebook/react@0700dd50b )**: Implement public instances for text nodes in Fabric ([#26516](facebook/react#26516)) //<Rubén Norte>// - **[4a1cc2ddd](facebook/react@4a1cc2ddd )**: Fix logic around attribute seralization ([#26526](facebook/react#26526)) //<Josh Story>// - **[7329ea81c](facebook/react@7329ea81c )**: Fix suspense replaying forward refs ([#26535](facebook/react#26535)) //<Hans Otto Wirtz>// - **[0ae348018](facebook/react@0ae348018 )**: [Float] Suspend unstyled content for up to 1 minute ([#26532](facebook/react#26532)) //<Andrew Clark>// - **[888874673](facebook/react@888874673 )**: Allow transitions to interrupt Suspensey commits ([#26531](facebook/react#26531)) //<Andrew Clark>// - **[09c8d2563](facebook/react@09c8d2563 )**: Move update scheduling to microtask ([#26512](facebook/react#26512)) //<Andrew Clark>// - **[8310854ce](facebook/react@8310854ce )**: Clean up enableCapturePhaseSelectiveHydrationWithoutDiscreteEventReplay ([#26521](facebook/react#26521)) //<Andrew Clark>// Changelog: [General][Changed] - React Native sync for revisions ca01f35...58742c2 jest_e2e[run_all_tests] bypass-github-export-checks Reviewed By: sammy-SC Differential Revision: D44872333 fbshipit-source-id: 0695e86645955aac7a20afdaf3ed02ad33592f5c
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This reverts commit 0b931f9.
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Updates that are marked as part of a transition are allowed to block a render from committing. Generally, other updates cannot — however, there's one exception that's leftover from a previous iteration of our Suspense architecture. If an update is not the result of a known urgent event type — known as "Default" updates — then we allow it to suspend briefly, as long as the delay is short enough that the user won't notice. We refer to this delay as a "Just Noticable Difference" (JND) delay. To illustrate, if the user has already waited 400ms for an update to be reflected on the screen, the theory is that they won't notice if you wait an additional 100ms. So React can suspend for a bit longer in case more data comes in. The longer the user has already waited, the longer the JND. While we still believe this theory is sound from a UX perspective, we no longer think the implementation complexity is worth it. The main thing that's changed is how we handle Default updates. We used to render Default updates concurrently (i.e. they were time sliced, and were scheduled with postTask), but now they are blocking. Soon, they will also be scheduled with rAF, too, which means by the end of the next rAF, they will have either finished rendering or the main thread will be blocked until they do. There are various motivations for this but part of the rationale is that anything that can be made non-blocking should be marked as a Transition, anyway, so it's not worth adding implementation complexity to Default. This commit removes the JND delay for Default updates. They will now commit immediately once the render phase is complete, even if a component suspends.
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May 7, 2023
Summary: This sync includes the following changes: - **[58742c21b](facebook/react@58742c21b )**: Delete unused `eventTimes` Fiber field ([facebook#26599](facebook/react#26599)) //<Andrew Clark>// - **[0b931f90e](facebook/react@0b931f90e )**: Remove JND delay for non-transition updates ([facebook#26597](facebook/react#26597)) //<Andrew Clark>// - **[ac43bf687](facebook/react@ac43bf687 )**: Move validation of text nesting into ReactDOMComponent ([facebook#26594](facebook/react#26594)) //<Sebastian Markbåge>// - **[ca41adb8c](facebook/react@ca41adb8c )**: Diff properties in the commit phase instead of generating an update payload ([facebook#26583](facebook/react#26583)) //<Sebastian Markbåge>// - **[dd0619b2e](facebook/react@dd0619b2e )**: rename $$$hostConfig to $$$config ([facebook#26593](facebook/react#26593)) //<Josh Story>// - **[b55d31955](facebook/react@b55d31955 )**: Rename HostConfig files to FiberConfig to clarify they are configs fo… ([facebook#26592](facebook/react#26592)) //<Josh Story>// - **[ffb8eaca5](facebook/react@ffb8eaca5 )**: Rename ReactServerFormatConfig to ReactFizzConfig ([facebook#26591](facebook/react#26591)) //<Josh Story>// - **[f4f873f62](facebook/react@f4f873f62 )**: Implements wiring for Flight to have it's own "HostConfig" ([facebook#26590](facebook/react#26590)) //<Josh Story>// - **[44db16afc](facebook/react@44db16afc )**: Normalize ReactFlightServerConfig and related files ([facebook#26589](facebook/react#26589)) //<Josh Story>// - **[fec97ecbc](facebook/react@fec97ecbc )**: act: Move didScheduleLegacyUpdate to ensureRootIsScheduled ([facebook#26552](facebook/react#26552)) //<Andrew Clark>// - **[9a9da7721](facebook/react@9a9da7721 )**: Don't update textarea defaultValue and input checked unnecessarily ([facebook#26580](facebook/react#26580)) //<Sebastian Markbåge>// - **[e5146cb52](facebook/react@e5146cb52 )**: Refactor some controlled component stuff ([facebook#26573](facebook/react#26573)) //<Sebastian Markbåge>// - **[657698e48](facebook/react@657698e48 )**: [Tests] `waitForThrow` should diff strings ([facebook#26568](facebook/react#26568)) //<Josh Story>// - **[85bb7b685](facebook/react@85bb7b685 )**: Fix: Move `destroy` field to shared instance object ([facebook#26561](facebook/react#26561)) //<Andrew Clark>// - **[9cfba0f6e](facebook/react@9cfba0f6e )**: Clean up discrete event replaying ([facebook#26558](facebook/react#26558)) //<Sebastian Markbåge>// - **[790ebc962](facebook/react@790ebc962 )**: Remove no-fallthrough lint suppressions ([facebook#26553](facebook/react#26553)) //<Sophie Alpert>// - **[c15579631](facebook/react@c15579631 )**: Put common aliases in Map/Set instead of switch over strings ([facebook#26551](facebook/react#26551)) //<Sebastian Markbåge>// - **[d5fd60f7e](facebook/react@d5fd60f7e )**: Remove findInstanceBlockingEvent unused parameters ([facebook#26534](facebook/react#26534)) //<Mohammad Ghorbani>// - **[eeabb7312](facebook/react@eeabb7312 )**: Refactor DOM Bindings Completely Off of DOMProperty Meta Programming ([facebook#26546](facebook/react#26546)) //<Sebastian Markbåge>// - **[da94e8b24](facebook/react@da94e8b24 )**: Revert "Cleanup enableSyncDefaultUpdate flag ([facebook#26236](facebook/react#26236))" ([facebook#26528](facebook/react#26528)) //<Jan Kassens>// - **[0700dd50b](facebook/react@0700dd50b )**: Implement public instances for text nodes in Fabric ([facebook#26516](facebook/react#26516)) //<Rubén Norte>// - **[4a1cc2ddd](facebook/react@4a1cc2ddd )**: Fix logic around attribute seralization ([facebook#26526](facebook/react#26526)) //<Josh Story>// - **[7329ea81c](facebook/react@7329ea81c )**: Fix suspense replaying forward refs ([facebook#26535](facebook/react#26535)) //<Hans Otto Wirtz>// - **[0ae348018](facebook/react@0ae348018 )**: [Float] Suspend unstyled content for up to 1 minute ([facebook#26532](facebook/react#26532)) //<Andrew Clark>// - **[888874673](facebook/react@888874673 )**: Allow transitions to interrupt Suspensey commits ([facebook#26531](facebook/react#26531)) //<Andrew Clark>// - **[09c8d2563](facebook/react@09c8d2563 )**: Move update scheduling to microtask ([facebook#26512](facebook/react#26512)) //<Andrew Clark>// - **[8310854ce](facebook/react@8310854ce )**: Clean up enableCapturePhaseSelectiveHydrationWithoutDiscreteEventReplay ([facebook#26521](facebook/react#26521)) //<Andrew Clark>// Changelog: [General][Changed] - React Native sync for revisions ca01f35...58742c2 jest_e2e[run_all_tests] bypass-github-export-checks Reviewed By: sammy-SC Differential Revision: D44872333 fbshipit-source-id: 0695e86645955aac7a20afdaf3ed02ad33592f5c
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May 22, 2023
Summary: This sync includes the following changes: - **[58742c21b](facebook/react@58742c21b )**: Delete unused `eventTimes` Fiber field ([facebook#26599](facebook/react#26599)) //<Andrew Clark>// - **[0b931f90e](facebook/react@0b931f90e )**: Remove JND delay for non-transition updates ([facebook#26597](facebook/react#26597)) //<Andrew Clark>// - **[ac43bf687](facebook/react@ac43bf687 )**: Move validation of text nesting into ReactDOMComponent ([facebook#26594](facebook/react#26594)) //<Sebastian Markbåge>// - **[ca41adb8c](facebook/react@ca41adb8c )**: Diff properties in the commit phase instead of generating an update payload ([facebook#26583](facebook/react#26583)) //<Sebastian Markbåge>// - **[dd0619b2e](facebook/react@dd0619b2e )**: rename $$$hostConfig to $$$config ([facebook#26593](facebook/react#26593)) //<Josh Story>// - **[b55d31955](facebook/react@b55d31955 )**: Rename HostConfig files to FiberConfig to clarify they are configs fo… ([facebook#26592](facebook/react#26592)) //<Josh Story>// - **[ffb8eaca5](facebook/react@ffb8eaca5 )**: Rename ReactServerFormatConfig to ReactFizzConfig ([facebook#26591](facebook/react#26591)) //<Josh Story>// - **[f4f873f62](facebook/react@f4f873f62 )**: Implements wiring for Flight to have it's own "HostConfig" ([facebook#26590](facebook/react#26590)) //<Josh Story>// - **[44db16afc](facebook/react@44db16afc )**: Normalize ReactFlightServerConfig and related files ([facebook#26589](facebook/react#26589)) //<Josh Story>// - **[fec97ecbc](facebook/react@fec97ecbc )**: act: Move didScheduleLegacyUpdate to ensureRootIsScheduled ([facebook#26552](facebook/react#26552)) //<Andrew Clark>// - **[9a9da7721](facebook/react@9a9da7721 )**: Don't update textarea defaultValue and input checked unnecessarily ([facebook#26580](facebook/react#26580)) //<Sebastian Markbåge>// - **[e5146cb52](facebook/react@e5146cb52 )**: Refactor some controlled component stuff ([facebook#26573](facebook/react#26573)) //<Sebastian Markbåge>// - **[657698e48](facebook/react@657698e48 )**: [Tests] `waitForThrow` should diff strings ([facebook#26568](facebook/react#26568)) //<Josh Story>// - **[85bb7b685](facebook/react@85bb7b685 )**: Fix: Move `destroy` field to shared instance object ([facebook#26561](facebook/react#26561)) //<Andrew Clark>// - **[9cfba0f6e](facebook/react@9cfba0f6e )**: Clean up discrete event replaying ([facebook#26558](facebook/react#26558)) //<Sebastian Markbåge>// - **[790ebc962](facebook/react@790ebc962 )**: Remove no-fallthrough lint suppressions ([facebook#26553](facebook/react#26553)) //<Sophie Alpert>// - **[c15579631](facebook/react@c15579631 )**: Put common aliases in Map/Set instead of switch over strings ([facebook#26551](facebook/react#26551)) //<Sebastian Markbåge>// - **[d5fd60f7e](facebook/react@d5fd60f7e )**: Remove findInstanceBlockingEvent unused parameters ([facebook#26534](facebook/react#26534)) //<Mohammad Ghorbani>// - **[eeabb7312](facebook/react@eeabb7312 )**: Refactor DOM Bindings Completely Off of DOMProperty Meta Programming ([facebook#26546](facebook/react#26546)) //<Sebastian Markbåge>// - **[da94e8b24](facebook/react@da94e8b24 )**: Revert "Cleanup enableSyncDefaultUpdate flag ([facebook#26236](facebook/react#26236))" ([facebook#26528](facebook/react#26528)) //<Jan Kassens>// - **[0700dd50b](facebook/react@0700dd50b )**: Implement public instances for text nodes in Fabric ([facebook#26516](facebook/react#26516)) //<Rubén Norte>// - **[4a1cc2ddd](facebook/react@4a1cc2ddd )**: Fix logic around attribute seralization ([facebook#26526](facebook/react#26526)) //<Josh Story>// - **[7329ea81c](facebook/react@7329ea81c )**: Fix suspense replaying forward refs ([facebook#26535](facebook/react#26535)) //<Hans Otto Wirtz>// - **[0ae348018](facebook/react@0ae348018 )**: [Float] Suspend unstyled content for up to 1 minute ([facebook#26532](facebook/react#26532)) //<Andrew Clark>// - **[888874673](facebook/react@888874673 )**: Allow transitions to interrupt Suspensey commits ([facebook#26531](facebook/react#26531)) //<Andrew Clark>// - **[09c8d2563](facebook/react@09c8d2563 )**: Move update scheduling to microtask ([facebook#26512](facebook/react#26512)) //<Andrew Clark>// - **[8310854ce](facebook/react@8310854ce )**: Clean up enableCapturePhaseSelectiveHydrationWithoutDiscreteEventReplay ([facebook#26521](facebook/react#26521)) //<Andrew Clark>// Changelog: [General][Changed] - React Native sync for revisions ca01f35...58742c2 jest_e2e[run_all_tests] bypass-github-export-checks Reviewed By: sammy-SC Differential Revision: D44872333 fbshipit-source-id: 0695e86645955aac7a20afdaf3ed02ad33592f5c
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Updates that are marked as part of a transition are allowed to block a render from committing. Generally, other updates cannot — however, there's one exception that's leftover from a previous iteration of our Suspense architecture. If an update is not the result of a known urgent event type — known as "Default" updates — then we allow it to suspend briefly, as long as the delay is short enough that the user won't notice. We refer to this delay as a "Just Noticable Difference" (JND) delay. To illustrate, if the user has already waited 400ms for an update to be reflected on the screen, the theory is that they won't notice if you wait an additional 100ms. So React can suspend for a bit longer in case more data comes in. The longer the user has already waited, the longer the JND. While we still believe this theory is sound from a UX perspective, we no longer think the implementation complexity is worth it. The main thing that's changed is how we handle Default updates. We used to render Default updates concurrently (i.e. they were time sliced, and were scheduled with postTask), but now they are blocking. Soon, they will also be scheduled with rAF, too, which means by the end of the next rAF, they will have either finished rendering or the main thread will be blocked until they do. There are various motivations for this but part of the rationale is that anything that can be made non-blocking should be marked as a Transition, anyway, so it's not worth adding implementation complexity to Default. This commit removes the JND delay for Default updates. They will now commit immediately once the render phase is complete, even if a component suspends.
bigfootjon
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Updates that are marked as part of a transition are allowed to block a render from committing. Generally, other updates cannot — however, there's one exception that's leftover from a previous iteration of our Suspense architecture. If an update is not the result of a known urgent event type — known as "Default" updates — then we allow it to suspend briefly, as long as the delay is short enough that the user won't notice. We refer to this delay as a "Just Noticable Difference" (JND) delay. To illustrate, if the user has already waited 400ms for an update to be reflected on the screen, the theory is that they won't notice if you wait an additional 100ms. So React can suspend for a bit longer in case more data comes in. The longer the user has already waited, the longer the JND. While we still believe this theory is sound from a UX perspective, we no longer think the implementation complexity is worth it. The main thing that's changed is how we handle Default updates. We used to render Default updates concurrently (i.e. they were time sliced, and were scheduled with postTask), but now they are blocking. Soon, they will also be scheduled with rAF, too, which means by the end of the next rAF, they will have either finished rendering or the main thread will be blocked until they do. There are various motivations for this but part of the rationale is that anything that can be made non-blocking should be marked as a Transition, anyway, so it's not worth adding implementation complexity to Default. This commit removes the JND delay for Default updates. They will now commit immediately once the render phase is complete, even if a component suspends. DiffTrain build for commit 0b931f9.
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Updates that are marked as part of a transition are allowed to block a render from committing. Generally, other updates cannot — however, there's one exception that's leftover from a previous iteration of our Suspense architecture. If an update is not the result of a known urgent event type — known as "Default" updates — then we allow it to suspend briefly, as long as the delay is short enough that the user won't notice. We refer to this delay as a "Just Noticable Difference" (JND) delay. To illustrate, if the user has already waited 400ms for an update to be reflected on the screen, the theory is that they won't notice if you wait an additional 100ms. So React can suspend for a bit longer in case more data comes in. The longer the user has already waited, the longer the JND.
While we still believe this theory is sound from a UX perspective, we no longer think the implementation complexity is worth it. The main thing that's changed is how we handle Default updates. We used to render Default updates concurrently (i.e. they were time sliced, and were scheduled with postTask), but now they are blocking. Soon, they will also be scheduled with rAF, too, which means by the end of the next rAF, they will have either finished rendering or the main thread will be blocked until they do. There are various motivations for this but part of the rationale is that anything that can be made non-blocking should be marked as a Transition, anyway, so it's not worth adding implementation complexity to Default.
This commit removes the JND delay for Default updates. They will now commit immediately once the render phase is complete, even if a component suspends.