Implement VirtualViewContainerStateExperimental (interval tree, updateModes optimization) #54213
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Summary: Introduces new React Native feature flag for VirtualViewContainerState versioning changes. Follow up diffs will create classic and experimental versions of VirtualViewContainerState. This feature flag is meant to eventually be overridden with MetaConfig variables. Differential Revision: D84569199
Summary: Removes unnecessary `debugLog` import in ReactVirtualViewExperimental and refactors the debug function Differential Revision: D84608555
…Android] Summary: Splits VirtualViewContainerState implementation into three parts: (1) an abstract parent class, (2) the "classic" version (existing version), and (3) the "experimental" version (new changes to be made). The experimental version is a copy of the classic version for now. Differential Revision: D84569206
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…eModes optimization) (facebook#54213) Summary: Pull Request resolved: facebook#54213 ## Changelog: [Internal] Modifies `VirtualViewContainerStateExperimental` to use an interval tree to store the container's VirtualViews. Interval tree's query allows us to lower the frequently-used updateModes() operation from `O(n)` to `O(m + log n)`, where `m` is the number of VirtualViews in the hysteresis range. General layout changes incur a penalty due to the requirement of maintaining a balanced BST. Performance Changes: * updateModes(): `O(n) -> O(m + log n)` (new algo) * updateMode(): `O(1) -> O(1)` * add VV: `O(1) -> O(log n)` * update VV: `O(1) -> O(log n)` * delete VV: `O(1) -> O(log n)` We expect scrolling to be much more frequent than a total layout change/updating many of the elements in the container at once. However, the initial load of a page will take `O(n log n)` time rather than `O(n)` time. We also include some bookkeeping sets for "old" hysteresis, prerender, and visible VVs. This will increase the memory footprint of `VirtualViewContainerState` by `O(m)`. More details are in https://docs.google.com/document/d/1Cmamx6fNfruoHLApX8tedqNVZsCEUyoBvQWpMvBsfcY/edit?tab=t.gqla6vu3231k. ### Note This diff only covers the Android version. iOS may follow after experimentation. Reviewed By: lunaleaps Differential Revision: D83783201
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…eModes optimization) (facebook#54213) Summary: Pull Request resolved: facebook#54213 ## Changelog: [Internal] Modifies `VirtualViewContainerStateExperimental` to use an interval tree to store the container's VirtualViews. Interval tree's query allows us to lower the frequently-used updateModes() operation from `O(n)` to `O(m + log n)`, where `m` is the number of VirtualViews in the hysteresis range. General layout changes incur a penalty due to the requirement of maintaining a balanced BST. Performance Changes: * updateModes(): `O(n) -> O(m + log n)` (new algo) * updateMode(): `O(1) -> O(1)` * add VV: `O(1) -> O(log n)` * update VV: `O(1) -> O(log n)` * delete VV: `O(1) -> O(log n)` We expect scrolling to be much more frequent than a total layout change/updating many of the elements in the container at once. However, the initial load of a page will take `O(n log n)` time rather than `O(n)` time. We also include some bookkeeping sets for "old" hysteresis, prerender, and visible VVs. This will increase the memory footprint of `VirtualViewContainerState` by `O(m)`. More details are in https://docs.google.com/document/d/1Cmamx6fNfruoHLApX8tedqNVZsCEUyoBvQWpMvBsfcY/edit?tab=t.gqla6vu3231k. ### Note This diff only covers the Android version. iOS may follow after experimentation. Reviewed By: lunaleaps Differential Revision: D83783201
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…eModes optimization) (facebook#54213) Summary: Pull Request resolved: facebook#54213 ## Changelog: [Internal] Modifies `VirtualViewContainerStateExperimental` to use an interval tree to store the container's VirtualViews. Interval tree's query allows us to lower the frequently-used updateModes() operation from `O(n)` to `O(m + log n)`, where `m` is the number of VirtualViews in the hysteresis range. General layout changes incur a penalty due to the requirement of maintaining a balanced BST. Performance Changes: * updateModes(): `O(n) -> O(m + log n)` (new algo) * updateMode(): `O(1) -> O(1)` * add VV: `O(1) -> O(log n)` * update VV: `O(1) -> O(log n)` * delete VV: `O(1) -> O(log n)` We expect scrolling to be much more frequent than a total layout change/updating many of the elements in the container at once. However, the initial load of a page will take `O(n log n)` time rather than `O(n)` time. We also include some bookkeeping sets for "old" hysteresis, prerender, and visible VVs. This will increase the memory footprint of `VirtualViewContainerState` by `O(m)`. More details are in https://docs.google.com/document/d/1Cmamx6fNfruoHLApX8tedqNVZsCEUyoBvQWpMvBsfcY/edit?tab=t.gqla6vu3231k. ### Note This diff only covers the Android version. iOS may follow after experimentation. Reviewed By: lunaleaps Differential Revision: D83783201
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…eModes optimization) (facebook#54213) Summary: Pull Request resolved: facebook#54213 ## Changelog: [Internal] Modifies `VirtualViewContainerStateExperimental` to use an interval tree to store the container's VirtualViews. Interval tree's query allows us to lower the frequently-used updateModes() operation from `O(n)` to `O(m + log n)`, where `m` is the number of VirtualViews in the hysteresis range. General layout changes incur a penalty due to the requirement of maintaining a balanced BST. Performance Changes: * updateModes(): `O(n) -> O(m + log n)` (new algo) * updateMode(): `O(1) -> O(1)` * add VV: `O(1) -> O(log n)` * update VV: `O(1) -> O(log n)` * delete VV: `O(1) -> O(log n)` We expect scrolling to be much more frequent than a total layout change/updating many of the elements in the container at once. However, the initial load of a page will take `O(n log n)` time rather than `O(n)` time. We also include some bookkeeping sets for "old" hysteresis, prerender, and visible VVs. This will increase the memory footprint of `VirtualViewContainerState` by `O(m)`. More details are in https://docs.google.com/document/d/1Cmamx6fNfruoHLApX8tedqNVZsCEUyoBvQWpMvBsfcY/edit?tab=t.gqla6vu3231k. ### Note This diff only covers the Android version. iOS may follow after experimentation. Reviewed By: lunaleaps Differential Revision: D83783201
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This pull request has been merged in 328d07a. |
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Summary:
Changelog: [Internal]
Modifies
VirtualViewContainerStateExperimentalto use an interval tree to store the container's VirtualViews. Interval tree's query allows us to lower the frequently-used updateModes() operation fromO(n)toO(m + log n), wheremis the number of VirtualViews in the hysteresis range. General layout changes incur a penalty due to the requirement of maintaining a balanced BST.Performance Changes:
O(n) -> O(m + log n)(new algo)O(1) -> O(1)O(1) -> O(log n)O(1) -> O(log n)O(1) -> O(log n)We expect scrolling to be much more frequent than a total layout change/updating many of the elements in the container at once. However, the initial load of a page will take
O(n log n)time rather thanO(n)time.We also include some bookkeeping sets for "old" hysteresis, prerender, and visible VVs. This will increase the memory footprint of
VirtualViewContainerStatebyO(m).Note
This diff only covers the Android version. iOS may follow after experimentation.
Reviewed By: lunaleaps
Differential Revision: D83783201