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[Merged by Bors] - Replace BlobVec's swap_scratch with a swap_nonoverlapping #4853
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hmm I was imagining just using |
swap_nonoverlapping needs a concrete type as generic parameter. As |
we can use |
Without something like |
We could simply allocate a |
What has the stack got to do with this, we can just use the memory in the blobvec cant we ? |
That is what was already happening before this PR. The motivation of this PR is that using the stack may be slightly faster due to cache locality reasons. I have no clue if this would indeed be the case. I think benchmarking will be needed. |
Before this PR the swap scratch was a separate allocation, wheras with this PR it's part of the same buffer as the rest of the blobvec. The part where the stack comes in is how to swap two different elements on the blobvec, and for that I think a simple swap_nonoverlapping with u8 type should work. |
Updated the PR to use
|
On a deeper inspection, it seems like we're doing one extra copy on
Ideally, we could just allocate in the target |
Revived this since there was an interest in optimizing the commands used in rendering. The components added/removed there can be quite big (140+ bytes), which lines up with some of the add/remove component benchmarks that saw a notable improvement here. Profiled this with tracy on This becomes a non-issue if #5037 is merged, as there are no heavy commands in that stage after that, but this is still a significant perf win we shouldn't ignore. Stage timings: Command timings: |
# Objective Speed up entity moves between tables by reducing the number of copies conducted. Currently three separate copies are conducted: `src[index] -> swap scratch`, `src[last] -> src[index]`, and `swap scratch -> dst[target]`. The first and last copies can be merged by directly using the copy `src[index] -> dst[target]`, which can save quite some time if the component(s) in question are large. ## Solution This PR does the following: - Adds `BlobVec::swap_remove_unchecked(usize, PtrMut<'_>)`, which is identical to `swap_remove_and_forget_unchecked`, but skips the `swap_scratch` and directly copies the component into the provided `PtrMut<'_>`. - Build `Column::initialize_from_unchecked(&mut Column, usize, usize)` which uses the above to directly initialize a row from another column. - Update most of the table move APIs to use `initialize_from_unchecked` instead of a combination of `swap_remove_and_forget_unchecked` and `initialize`. This is an alternative, though orthogonal, approach to achieve the same performance gains as seen in #4853. This (hopefully) shouldn't run into the same Miri limitations that said PR currently does. After this PR, `swap_remove_and_forget_unchecked` is still in use for Resources and swap_scratch likely still should be removed, so #4853 still has use, even if this PR is merged. ## Performance TODO: Microbenchmark This PR shows similar improvements to commands that add or remove table components that result in a table move. When tested on `many_cubes sphere`, some of the more command heavy systems saw notable improvements. In particular, `prepare_uniform_components<T>`, this saw a reduction in time from 1.35ms to 1.13ms (a 16.3% improvement) on my local machine, a similar if not slightly better gain than what #4853 showed [here](#4853 (comment)). ![image](https://user-images.githubusercontent.com/3137680/174570088-1c4c6fd7-3215-478c-9eb7-8bd9fe486b32.png) The command heavy `Extract` stage also saw a smaller overall improvement: ![image](https://user-images.githubusercontent.com/3137680/174572261-8a48f004-ab9f-4cb2-b304-a882b6d78065.png) --- ## Changelog Added: `BlobVec::swap_remove_unchecked`. Added: `Column::initialize_from_unchecked`.
# Objective Speed up entity moves between tables by reducing the number of copies conducted. Currently three separate copies are conducted: `src[index] -> swap scratch`, `src[last] -> src[index]`, and `swap scratch -> dst[target]`. The first and last copies can be merged by directly using the copy `src[index] -> dst[target]`, which can save quite some time if the component(s) in question are large. ## Solution This PR does the following: - Adds `BlobVec::swap_remove_unchecked(usize, PtrMut<'_>)`, which is identical to `swap_remove_and_forget_unchecked`, but skips the `swap_scratch` and directly copies the component into the provided `PtrMut<'_>`. - Build `Column::initialize_from_unchecked(&mut Column, usize, usize)` on top of it, which uses the above to directly initialize a row from another column. - Update most of the table move APIs to use `initialize_from_unchecked` instead of a combination of `swap_remove_and_forget_unchecked` and `initialize`. This is an alternative, though orthogonal, approach to achieve the same performance gains as seen in #4853. This (hopefully) shouldn't run into the same Miri limitations that said PR currently does. After this PR, `swap_remove_and_forget_unchecked` is still in use for Resources and swap_scratch likely still should be removed, so #4853 still has use, even if this PR is merged. ## Performance TODO: Microbenchmark This PR shows similar improvements to commands that add or remove table components that result in a table move. When tested on `many_cubes sphere`, some of the more command heavy systems saw notable improvements. In particular, `prepare_uniform_components<T>`, this saw a reduction in time from 1.35ms to 1.13ms (a 16.3% improvement) on my local machine, a similar if not slightly better gain than what #4853 showed [here](#4853 (comment)). ![image](https://user-images.githubusercontent.com/3137680/174570088-1c4c6fd7-3215-478c-9eb7-8bd9fe486b32.png) The command heavy `Extract` stage also saw a smaller overall improvement: ![image](https://user-images.githubusercontent.com/3137680/174572261-8a48f004-ab9f-4cb2-b304-a882b6d78065.png) --- ## Changelog Added: `BlobVec::swap_remove_unchecked`. Added: `Column::initialize_from_unchecked`.
…ne#5056) # Objective Speed up entity moves between tables by reducing the number of copies conducted. Currently three separate copies are conducted: `src[index] -> swap scratch`, `src[last] -> src[index]`, and `swap scratch -> dst[target]`. The first and last copies can be merged by directly using the copy `src[index] -> dst[target]`, which can save quite some time if the component(s) in question are large. ## Solution This PR does the following: - Adds `BlobVec::swap_remove_unchecked(usize, PtrMut<'_>)`, which is identical to `swap_remove_and_forget_unchecked`, but skips the `swap_scratch` and directly copies the component into the provided `PtrMut<'_>`. - Build `Column::initialize_from_unchecked(&mut Column, usize, usize)` on top of it, which uses the above to directly initialize a row from another column. - Update most of the table move APIs to use `initialize_from_unchecked` instead of a combination of `swap_remove_and_forget_unchecked` and `initialize`. This is an alternative, though orthogonal, approach to achieve the same performance gains as seen in bevyengine#4853. This (hopefully) shouldn't run into the same Miri limitations that said PR currently does. After this PR, `swap_remove_and_forget_unchecked` is still in use for Resources and swap_scratch likely still should be removed, so bevyengine#4853 still has use, even if this PR is merged. ## Performance TODO: Microbenchmark This PR shows similar improvements to commands that add or remove table components that result in a table move. When tested on `many_cubes sphere`, some of the more command heavy systems saw notable improvements. In particular, `prepare_uniform_components<T>`, this saw a reduction in time from 1.35ms to 1.13ms (a 16.3% improvement) on my local machine, a similar if not slightly better gain than what bevyengine#4853 showed [here](bevyengine#4853 (comment)). ![image](https://user-images.githubusercontent.com/3137680/174570088-1c4c6fd7-3215-478c-9eb7-8bd9fe486b32.png) The command heavy `Extract` stage also saw a smaller overall improvement: ![image](https://user-images.githubusercontent.com/3137680/174572261-8a48f004-ab9f-4cb2-b304-a882b6d78065.png) --- ## Changelog Added: `BlobVec::swap_remove_unchecked`. Added: `Column::initialize_from_unchecked`.
…ne#5056) # Objective Speed up entity moves between tables by reducing the number of copies conducted. Currently three separate copies are conducted: `src[index] -> swap scratch`, `src[last] -> src[index]`, and `swap scratch -> dst[target]`. The first and last copies can be merged by directly using the copy `src[index] -> dst[target]`, which can save quite some time if the component(s) in question are large. ## Solution This PR does the following: - Adds `BlobVec::swap_remove_unchecked(usize, PtrMut<'_>)`, which is identical to `swap_remove_and_forget_unchecked`, but skips the `swap_scratch` and directly copies the component into the provided `PtrMut<'_>`. - Build `Column::initialize_from_unchecked(&mut Column, usize, usize)` on top of it, which uses the above to directly initialize a row from another column. - Update most of the table move APIs to use `initialize_from_unchecked` instead of a combination of `swap_remove_and_forget_unchecked` and `initialize`. This is an alternative, though orthogonal, approach to achieve the same performance gains as seen in bevyengine#4853. This (hopefully) shouldn't run into the same Miri limitations that said PR currently does. After this PR, `swap_remove_and_forget_unchecked` is still in use for Resources and swap_scratch likely still should be removed, so bevyengine#4853 still has use, even if this PR is merged. ## Performance TODO: Microbenchmark This PR shows similar improvements to commands that add or remove table components that result in a table move. When tested on `many_cubes sphere`, some of the more command heavy systems saw notable improvements. In particular, `prepare_uniform_components<T>`, this saw a reduction in time from 1.35ms to 1.13ms (a 16.3% improvement) on my local machine, a similar if not slightly better gain than what bevyengine#4853 showed [here](bevyengine#4853 (comment)). ![image](https://user-images.githubusercontent.com/3137680/174570088-1c4c6fd7-3215-478c-9eb7-8bd9fe486b32.png) The command heavy `Extract` stage also saw a smaller overall improvement: ![image](https://user-images.githubusercontent.com/3137680/174572261-8a48f004-ab9f-4cb2-b304-a882b6d78065.png) --- ## Changelog Added: `BlobVec::swap_remove_unchecked`. Added: `Column::initialize_from_unchecked`.
rust-lang/rust#104054 should fix the miri issue. Once this is ready in nightly, this PR should be mergable. |
bors r+ |
# Objective BlobVec currently relies on a scratch piece of memory allocated at initialization to make a temporary copy of a component when using `swap_remove_and_{forget/drop}`. This is potentially suboptimal as it writes to a, well-known, but random part of memory instead of using the stack. ## Solution As the `FIXME` in the file states, replace `swap_scratch` with a call to `swap_nonoverlapping::<u8>`. The swapped last entry is returned as a `OwnedPtr`. In theory, this should be faster as the temporary swap is allocated on the stack, `swap_nonoverlapping` allows for easier vectorization for bigger types, and the same memory is used between the swap and the returned `OwnedPtr`.
# Objective BlobVec currently relies on a scratch piece of memory allocated at initialization to make a temporary copy of a component when using `swap_remove_and_{forget/drop}`. This is potentially suboptimal as it writes to a, well-known, but random part of memory instead of using the stack. ## Solution As the `FIXME` in the file states, replace `swap_scratch` with a call to `swap_nonoverlapping::<u8>`. The swapped last entry is returned as a `OwnedPtr`. In theory, this should be faster as the temporary swap is allocated on the stack, `swap_nonoverlapping` allows for easier vectorization for bigger types, and the same memory is used between the swap and the returned `OwnedPtr`.
…ne#5056) # Objective Speed up entity moves between tables by reducing the number of copies conducted. Currently three separate copies are conducted: `src[index] -> swap scratch`, `src[last] -> src[index]`, and `swap scratch -> dst[target]`. The first and last copies can be merged by directly using the copy `src[index] -> dst[target]`, which can save quite some time if the component(s) in question are large. ## Solution This PR does the following: - Adds `BlobVec::swap_remove_unchecked(usize, PtrMut<'_>)`, which is identical to `swap_remove_and_forget_unchecked`, but skips the `swap_scratch` and directly copies the component into the provided `PtrMut<'_>`. - Build `Column::initialize_from_unchecked(&mut Column, usize, usize)` on top of it, which uses the above to directly initialize a row from another column. - Update most of the table move APIs to use `initialize_from_unchecked` instead of a combination of `swap_remove_and_forget_unchecked` and `initialize`. This is an alternative, though orthogonal, approach to achieve the same performance gains as seen in bevyengine#4853. This (hopefully) shouldn't run into the same Miri limitations that said PR currently does. After this PR, `swap_remove_and_forget_unchecked` is still in use for Resources and swap_scratch likely still should be removed, so bevyengine#4853 still has use, even if this PR is merged. ## Performance TODO: Microbenchmark This PR shows similar improvements to commands that add or remove table components that result in a table move. When tested on `many_cubes sphere`, some of the more command heavy systems saw notable improvements. In particular, `prepare_uniform_components<T>`, this saw a reduction in time from 1.35ms to 1.13ms (a 16.3% improvement) on my local machine, a similar if not slightly better gain than what bevyengine#4853 showed [here](bevyengine#4853 (comment)). ![image](https://user-images.githubusercontent.com/3137680/174570088-1c4c6fd7-3215-478c-9eb7-8bd9fe486b32.png) The command heavy `Extract` stage also saw a smaller overall improvement: ![image](https://user-images.githubusercontent.com/3137680/174572261-8a48f004-ab9f-4cb2-b304-a882b6d78065.png) --- ## Changelog Added: `BlobVec::swap_remove_unchecked`. Added: `Column::initialize_from_unchecked`.
…#4853) # Objective BlobVec currently relies on a scratch piece of memory allocated at initialization to make a temporary copy of a component when using `swap_remove_and_{forget/drop}`. This is potentially suboptimal as it writes to a, well-known, but random part of memory instead of using the stack. ## Solution As the `FIXME` in the file states, replace `swap_scratch` with a call to `swap_nonoverlapping::<u8>`. The swapped last entry is returned as a `OwnedPtr`. In theory, this should be faster as the temporary swap is allocated on the stack, `swap_nonoverlapping` allows for easier vectorization for bigger types, and the same memory is used between the swap and the returned `OwnedPtr`.
## How This Works For the Bevy 0.10 release blog post (and for the first time ever), I'm publicly opening the doors to other people writing blog post sections. Specifically, if you worked on a feature in a substantial way and are interested in presenting it, you can now ask to claim a section by leaving a comment in this PR. If you claim a section, submit a pull request to the `release-0.10.0` branch in this repo. For the next week, we will be filling in sections (the release target is Saturday March 4th). Please don't claim a section if you don't plan on completing it within that timeline. Also don't claim a section if you weren't an active participant in the design and implementation of the change (unless you are a Maintainer or SME). I will claim any unclaimed sections. Try to match the style of previous release blog posts as much as possible. 1. Show, don't tell. Don't bombard people with information. Avoid large walls of text _and_ large walls of code. Prefer the pattern "byte sized description of one thing" -> "example code/picture/video contextualizing that one thing" -> repeat. Take readers on a journey step by simple step. 2. Don't use up reader's "mental bandwidth" without good reason. We can't afford page-long descriptions of minor bug fixes. If it isn't a "headliner change", keep the description short and sweet. If a change is self describing, let it do that (ex: We now support this new mesh shape primitive ... this is what it looks like). If it is a "headliner change", still try to keep it reasonable. We always have a lot to cover. 3. In slight competition with point (2), don't omit interesting technical information when it is truly fun and engaging. A good chunk of our users are highly technical and enjoy learning how the sausage is made. Try to strike a balance between "terse and simple" and "nerdy details". 4. When relevant, briefly describe the problem being solved first, then describe the solution we chose. This contextualizes the change and gives the feature value and purpose. 5. When possible, provide visuals. They create interest / keep people hooked / break up the monotony. 6. Record images and videos at the default bevy resolution (1280x720) 7. Provide an accurate listing of authors that meaningfully contributed to the feature. Try to sort in order of "contribution scale". This is hard to define, but try to be fair. When in doubt, ask other contributors, SMEs, and/or maintainers. 8. Provide numbers and graphs where possible. If something is faster, use numbers to back it up. We don't (yet) have automated graph generation in blog post style, so send data / info to me (@cart) if you want a graph made. ## Headliners Headliners are our "big ticket high importance / high profile" changes. They are listed briefly at the beginning of the blog post, their entries are roughly sorted "to the top", and they are given priority when it comes to "space in the blog post". If you think we missed something (or didn't prioritize something appropriately), let us know. * ECS Schedule v3 (previously known as "stageless") * Partial Android Support * Depth and Normal Prepass * Environment Map Lighting * Cascaded Shadow Maps * Distance and Atmospheric Fog * Smooth Skeletal Animation Transitions * Enable Parallel Pipelined Rendering * Windows as Entities * Renderer Optimizations * ECS Optimizations ## Sections These are the sections we will cover in the blog post. If a section has been claimed, it will have `(claimed by X)` in the title. If it is unclaimed it will have `(unclaimed)` in the title. Let us know if we missed a section. We don't cover every feature, but we should cover pretty much everything that would be interesting to users. Note that what is interesting or challenging to implement is not necessarily something that is relevant to our blog post readers. And sometimes the reverse is true! If you believe a section should be split up or reorganized, just bring it up here and we can discuss it. ### ~~Schedule V3 (claimed by @alice-i-cecile)~~ * [Migrate engine to Schedule v3][7267] * [Add `bevy_ecs::schedule_v3` module][6587] * [Stageless: fix unapplied systems][7446] * [Stageless: move final apply outside of spawned executor][7445] * Sets * Base Sets * [Base Sets][7466] * Reporting * [Report sets][7756] * [beter cycle reporting][7463] * Run Conditions * [Add condition negation][7559] * [And/Or][7605] * [Add more common run conditions][7579] * States * [States derive macro][7535] * System Piping Flexibility * [Support piping exclusive systems][7023] * [Allow piping run conditions][7547] ### ~~Depth and Normal Prepass (claimed by @IceSentry)~~ * [Add depth and normal prepass][6284] * [Move prepass functions to prepass_utils][7354] ### ~~Distance and Atmospheric Fog (claimed by @coreh)~~ * [Add Distance and Atmospheric Fog support][6412] ### ~~Cascaded Shadow Maps (claimed by @cart)~~ * [Cascaded shadow maps.][7064] * [Better cascades config defaults + builder, tweak example configs][7456] ### ~~Environment Map Lighting (claimed by @cart)~~ * [EnvironmentMapLight, BRDF Improvements][7051] * [Webgl2 support][7737] ### ~~Tonemapping options (claimed by @cart)~~ * [Initial tonemapping options][7594] ### ~~Android support + unification (claimed by @mockersf)~~ * [IOS, Android... same thing][7493] ### ~~Windows as Entities (claimed by @Aceeri)~~ * [Windows as Entities][5589] * [break feedback loop when moving cursor][7298] * [Fix `Window` feedback loop between the OS and Bevy][7517] ### ~~Enable Parallel Pipelined Rendering (claimed by @james7132)~~ * [Pipelined Rendering][6503] * [Stageless: add a method to scope to always run a task on the scope thread][7415] * [Separate Extract from Sub App Schedule][7046] ### ~~Smooth Skeletal Animation Transitions (claimed by @james7132)~~ * [Smooth Transition between Animations][6922] ### ~~Spatial Audio (claimed by @harudagondi)~~ * [Spatial Audio][6028] ### ~~Shader Processor Features (claimed by @cart)~~ * [Shader defs can now have a value][5900] * [Shaders can now have #else ifdef chains][7431] * [Define shader defs in shader][7518] ### ~~Shader Flexibility Improvements (claimed by @cart)~~ * [add ambient lighting hook][5428] * [Refactor Globals and View structs into separate shaders][7512] ### ~~Renderer Optimizations (claimed by @james7132)~~ * [bevy_pbr: Avoid copying structs and using registers in shaders][7069] * [Flatten render commands][6885] * [Replace UUID based IDs with a atomic-counted ones][6988] * [improve compile time by type-erasing wgpu structs][5950] * [Shrink DrawFunctionId][6944] * [Shrink ComputedVisibility][6305] * [Reduce branching in TrackedRenderPass][7053] * [Make PipelineCache internally mutable.][7205] * [Improve `Color::hex` performance][6940] * [Support recording multiple CommandBuffers in RenderContext][7248] * [Parallelized transform propagation][4775] * [Introduce detailed_trace macro, use in TrackedRenderPass][7639] * [Optimize color computation in prepare_uinodes][7311] * [Directly extract joints into SkinnedMeshJoints][6833] * [Parallelize forward kinematics animation systems][6785] * [Move system_commands spans into apply_buffers][6900] * [Reduce the use of atomics in the render phase][7084] ### ~~ECS Optimizations (claimed by @james7132 )~~ * [Remove redundant table and sparse set component IDs from Archetype][4927] * [Immutable sparse sets for metadata storage][4928] * [Replace BlobVec's swap_scratch with a swap_nonoverlapping][4853] * [Use T::Storage::STORAGE_TYPE to optimize out unused branches][6800] * [Remove unnecessary branching from bundle insertion][6902] * [Split Component Ticks][6547] * [use bevy_utils::HashMap for better performance. TypeId is predefined …][7642] * [Extend EntityLocation with TableId and TableRow][6681] * [Basic adaptive batching for parallel quer- [Speed up `CommandQueue` by storing commands more densely][6391]y iteration][4777] ### ~~Reflect Improvements (claimed by @cart)~~ * [bevy_reflect: Add `ReflectFromReflect` (v2)][6245] * [Add reflection support for VecDeque][6831] * [reflect: add `insert` and `remove` methods to `List`][7063] * [Add `remove` method to `Map` reflection trait.][6564] * [bevy_reflect: Fix binary deserialization not working for unit structs][6722] * [Add `TypeRegistrationDeserializer` and remove `BorrowedStr`][7094] * [bevy_reflect: Add simple enum support to reflection paths][6560] * [Enable deriving Reflect on structs with generic types][7364] * [bevy_reflect: Support tuple reflection paths][7324] * [bevy_reflect: Pre-parsed paths][7321] * [bevy_ecs: ReflectComponentFns without World][7206] ### ~~AsBindGroup Improvements (claimed by @cart)~~ * [Support storage buffers in derive `AsBindGroup`][6129] * [Support raw buffers in AsBindGroup][7701] ### ~~Cylinder Shape (claimed by @cart)~~ * [Add cylinder shape][6809] ### ~~Subdividable Plane Shape (claimed by @cart)~~ * [added subdivisions to shape::Plane][7546] ### ~~StandardMaterial Blend Modes (claimed by @coreh)~~ * [Standard Material Blend Modes][6644] ### ~~Configurable Visibility Component (claimed by @cart)~~ * [enum `Visibility` component][6320] ### Task Improvements (claimed by @cart) * [Fix panicking on another scope][6524] * [Add thread create/destroy callbacks to TaskPool][6561] * [Thread executor for running tasks on specific threads.][7087] * [await tasks to cancel][6696] * [Stageless: move MainThreadExecutor to schedule_v3][7444] * [Stageless: close the finish channel so executor doesn't deadlock][7448] ### ~~Upgrade to wgpu 0.15 (claimed by @cart)~~ * [Wgpu 0.15][7356] ### ~~Expose Bindless / Non-uniform Indexing Support (claimed by @cart)~~ * [Request WGPU Capabilities for Non-uniform Indexing][6995] ### ~~Cubic Spline (claimed by @aevyrie)~~ * [Bezier][7653] ### ~~Revamp Bloom (claimed by @JMS55)~~ * [Revamp bloom](bevyengine/bevy#6677) ### ~~Use Prepass Shaders for Shadows (claimed by @superdump)~~ * [use prepass shaders for shadows](bevyengine/bevy#7784) ### ~~AccessKit (claimed by @alice-i-cecile)~~ * [accesskit](bevyengine/bevy#6874) ### ~~Camera Output Modes (claimed by @cart)~~ * [camera output modes](bevyengine/bevy#7671) ### ~~SystemParam Improvements (claimed by @JoJoJet)~~ * [Make the `SystemParam` derive macro more flexible][6694] * [Add a `SystemParam` primitive for deferred mutations; allow `#[derive]`ing more types of SystemParam][6817] ### ~~Gamepad Improvements (claimed by @cart)~~ * [Gamepad events refactor][6965] * [add `Axis::devices` to get all the input devices][5400] ### ~~Input Methods (claimed by @cart)~~ * [add Input Method Editor support][7325] ### ~~Color Improvements (claimed by @cart)~~ * [Add LCH(ab) color space to `bevy_render::color::Color`][7483] * [Add a more familiar hex color entry][7060] ### ~~Split Up CorePlugin (claimed by @cart)~~ * [Break `CorePlugin` into `TaskPoolPlugin`, `TypeRegistrationPlugin`, `FrameCountPlugin`.][7083] ### ~~ExtractComponent Derive (claimed by @cart)~~ * [Extract component derive][7399] ### ~~Added OpenGL and DX11 Backends By Default (claimed by @cart)~~ * [add OpenGL and DX11 backends][7481] ### ~~UnsafeWorldCell (claimed by @BoxyUwU)~~ * [Move all logic to `UnsafeWorldCell`][7381] * [Rename `UnsafeWorldCellEntityRef` to `UnsafeEntityCell`][7568] ### ~~Entity Commands (claimed by @cart)~~ * [Add a trait for commands that run for a given `Entity`][7015] * [Add an extension trait to `EntityCommands` to update hierarchy while preserving `GlobalTransform`][7024] * [Add ReplaceChildren and ClearChildren EntityCommands][6035] ### ~~Iterate EntityRef (claimed by @james7132)~~ * [Allow iterating over with EntityRef over the entire World][6843] ### ~~Ref Queries (@JoJoJet)~~ * [Added Ref to allow immutable access with change detection][7097] ### ~~Taffy Upgrade (claimed by @cart)~~ * [Upgrade to Taffy 0.2][6743] ### ~~Relative Cursor Position (claimed by @cart)~~ * [Relative cursor position][7199] ### ~~Const UI Config (claimed by @cart)~~ * [Add const to methods and const defaults to bevy_ui][5542] ### ~~Examples (claimed by @cart)~~ * [Add pixelated Bevy to assets and an example][6408] * [Organized scene_viewer into plugins for reuse and organization][6936] ### ~~CI Improvements (claimed by @cart)~~ * [add rust-version for MSRV and CI job to check][6852] * [msrv: only send a message on failure during the actual msrv part][7532] * [Make CI friendlier][7398] * [Fix CI welcome message][7428] * [add an action to ask for a migration guide when one is missing][7507] ### ~~SMEs (@cart)~~ This was already covered in another blog post. Just briefly call out what they are and that this is the first release that used them. Link to the other blog post. * [Subject Matter Experts and new Bevy Org docs][7185] [4775]: bevyengine/bevy#4775 [4777]: bevyengine/bevy#4777 [4853]: bevyengine/bevy#4853 [4927]: bevyengine/bevy#4927 [4928]: bevyengine/bevy#4928 [5400]: bevyengine/bevy#5400 [5428]: bevyengine/bevy#5428 [5542]: bevyengine/bevy#5542 [5589]: bevyengine/bevy#5589 [5900]: bevyengine/bevy#5900 [5950]: bevyengine/bevy#5950 [6028]: bevyengine/bevy#6028 [6035]: bevyengine/bevy#6035 [6129]: bevyengine/bevy#6129 [6179]: bevyengine/bevy#6179 [6245]: bevyengine/bevy#6245 [6284]: bevyengine/bevy#6284 [6305]: bevyengine/bevy#6305 [6320]: bevyengine/bevy#6320 [6391]: bevyengine/bevy#6391 [6408]: bevyengine/bevy#6408 [6412]: bevyengine/bevy#6412 [6503]: bevyengine/bevy#6503 [6524]: bevyengine/bevy#6524 [6547]: bevyengine/bevy#6547 [6557]: bevyengine/bevy#6557 [6560]: bevyengine/bevy#6560 [6561]: bevyengine/bevy#6561 [6564]: bevyengine/bevy#6564 [6587]: bevyengine/bevy#6587 [6644]: bevyengine/bevy#6644 [6649]: bevyengine/bevy#6649 [6681]: bevyengine/bevy#6681 [6694]: bevyengine/bevy#6694 [6696]: bevyengine/bevy#6696 [6722]: bevyengine/bevy#6722 [6743]: bevyengine/bevy#6743 [6785]: bevyengine/bevy#6785 [6800]: bevyengine/bevy#6800 [6802]: bevyengine/bevy#6802 [6809]: bevyengine/bevy#6809 [6817]: bevyengine/bevy#6817 [6831]: bevyengine/bevy#6831 [6833]: bevyengine/bevy#6833 [6843]: bevyengine/bevy#6843 [6852]: bevyengine/bevy#6852 [6885]: bevyengine/bevy#6885 [6900]: bevyengine/bevy#6900 [6902]: bevyengine/bevy#6902 [6922]: bevyengine/bevy#6922 [6926]: bevyengine/bevy#6926 [6936]: bevyengine/bevy#6936 [6940]: bevyengine/bevy#6940 [6944]: bevyengine/bevy#6944 [6965]: bevyengine/bevy#6965 [6988]: bevyengine/bevy#6988 [6995]: bevyengine/bevy#6995 [7015]: bevyengine/bevy#7015 [7023]: bevyengine/bevy#7023 [7024]: bevyengine/bevy#7024 [7046]: bevyengine/bevy#7046 [7051]: bevyengine/bevy#7051 [7053]: bevyengine/bevy#7053 [7060]: bevyengine/bevy#7060 [7063]: bevyengine/bevy#7063 [7064]: bevyengine/bevy#7064 [7069]: bevyengine/bevy#7069 [7083]: bevyengine/bevy#7083 [7084]: bevyengine/bevy#7084 [7087]: bevyengine/bevy#7087 [7094]: bevyengine/bevy#7094 [7097]: bevyengine/bevy#7097 [7185]: bevyengine/bevy#7185 [7199]: bevyengine/bevy#7199 [7205]: bevyengine/bevy#7205 [7206]: bevyengine/bevy#7206 [7248]: bevyengine/bevy#7248 [7267]: bevyengine/bevy#7267 [7298]: bevyengine/bevy#7298 [7311]: bevyengine/bevy#7311 [7321]: bevyengine/bevy#7321 [7324]: bevyengine/bevy#7324 [7325]: bevyengine/bevy#7325 [7354]: bevyengine/bevy#7354 [7356]: bevyengine/bevy#7356 [7364]: bevyengine/bevy#7364 [7381]: bevyengine/bevy#7381 [7398]: bevyengine/bevy#7398 [7399]: bevyengine/bevy#7399 [7415]: bevyengine/bevy#7415 [7428]: bevyengine/bevy#7428 [7431]: bevyengine/bevy#7431 [7444]: bevyengine/bevy#7444 [7445]: bevyengine/bevy#7445 [7446]: bevyengine/bevy#7446 [7448]: bevyengine/bevy#7448 [7456]: bevyengine/bevy#7456 [7463]: bevyengine/bevy#7463 [7466]: bevyengine/bevy#7466 [7481]: bevyengine/bevy#7481 [7483]: bevyengine/bevy#7483 [7493]: bevyengine/bevy#7493 [7507]: bevyengine/bevy#7507 [7510]: bevyengine/bevy#7510 [7512]: bevyengine/bevy#7512 [7517]: bevyengine/bevy#7517 [7518]: bevyengine/bevy#7518 [7532]: bevyengine/bevy#7532 [7535]: bevyengine/bevy#7535 [7546]: bevyengine/bevy#7546 [7547]: bevyengine/bevy#7547 [7559]: bevyengine/bevy#7559 [7568]: bevyengine/bevy#7568 [7579]: bevyengine/bevy#7579 [7594]: bevyengine/bevy#7594 [7605]: bevyengine/bevy#7605 [7639]: bevyengine/bevy#7639 [7642]: bevyengine/bevy#7642 [7653]: bevyengine/bevy#7653 [7701]: bevyengine/bevy#7701 [7737]: bevyengine/bevy#7737 [7756]: bevyengine/bevy#7756 Co-authored-by: François <mockersf@gmail.com> Co-authored-by: Alice Cecile <alice.i.cecile@gmail.com> Co-authored-by: Mike <mike.hsu@gmail.com> Co-authored-by: Boxy <supbscripter@gmail.com> Co-authored-by: IceSentry <c.giguere42@gmail.com> Co-authored-by: JoJoJet <21144246+JoJoJet@users.noreply.github.com> Co-authored-by: Aevyrie <aevyrie@gmail.com> Co-authored-by: James Liu <contact@jamessliu.com> Co-authored-by: Marco Buono <thecoreh@gmail.com> Co-authored-by: Aceeri <conmcclusk@gmail.com>
Objective
BlobVec currently relies on a scratch piece of memory allocated at initialization to make a temporary copy of a component when using
swap_remove_and_{forget/drop}
. This is potentially suboptimal as it writes to a, well-known, but random part of memory instead of using the stack.Solution
As the
FIXME
in the file states, replaceswap_scratch
with a call toswap_nonoverlapping::<u8>
. The swapped last entry is returned as aOwnedPtr
.In theory, this should be faster as the temporary swap is allocated on the stack,
swap_nonoverlapping
allows for easier vectorization for bigger types, and the same memory is used between the swap and the returnedOwnedPtr
.