[Merged by Bors] - Immutable sparse sets for metadata storage #4928

james7132 · 2022-06-04T22:03:13Z

Objective

Make core types in ECS smaller. The column sparse set in Tables is never updated after creation.

Solution

Create ImmutableSparseSet which removes the capacity fields in the backing vec's and the APIs for inserting or removing elements. Drops the size of the sparse set by 3 usizes (24 bytes on 64-bit systems)

Followup

~~After #4809, Archetype's component SparseSet should be replaced with it.~~ This has been done.

Changelog

Removed: Table::component_capacity

Migration Guide

Table::component_capacity() has been removed as Tables do not support adding/removing columns after construction.

crates/bevy_ecs/src/storage/sparse_set.rs

crates/bevy_ecs/src/storage/table.rs

alice-i-cecile

The strategy makes sense to me, but this needs docs. The internals are slowly getting less intimidating, let's not reverse that trend.

alice-i-cecile

I'm happy with this now. I think it's unlikely that we ever will ever want to remove columns (i.e. registered resource / component types), even once we start doing empty archetype cleanup. And if we do, this is a more fair comparison for benchmarks.

crates/bevy_ecs/src/storage/sparse_set.rs

Co-authored-by: Kristoffer Søholm <k.soeholm@gmail.com>

Diddykonga

LGTM
Don't personally like simple macro usage, but I digress.

cart · 2022-11-15T21:05:05Z

crates/bevy_ecs/src/storage/table.rs

+impl TableBuilder {
+    /// Creates a blank [`Table`], allocating space for `column_capacity` columns
+    /// with the capacity to hold `capacity` entities worth of components each.
+    pub fn with_capacity(capacity: usize, column_capacity: usize) -> Self {


Is there a chance that we end up realloc-ing our tables on construction in some / all cases, due to the fact that with_capacity isn't guaranteed to allocate exactly capacity, but shrink_to_fit will shrink to capacity?

There is, but unless we're constantly making new Tables and Archetypes, the cost IMO is negligible over the lifetime of the app.

The frequency might go up drastically if we start doing "fragmenting relations". In that context the bytes saved might not be worth it. Hard to say what to value more.

I guess if/when we implement fragmenting relations we can let benchmarks decide. But this level of nuance is easy to forget about.

cart · 2022-11-15T21:51:08Z

Probably going to conflict with #4927 but lets give it a try

cart · 2022-11-15T21:51:14Z

bors r+

bors · 2022-11-15T21:55:49Z

Merge conflict.

james7132 · 2022-11-15T22:21:02Z

bors retry

# Objective Make core types in ECS smaller. The column sparse set in Tables is never updated after creation. ## Solution Create `ImmutableSparseSet` which removes the capacity fields in the backing vec's and the APIs for inserting or removing elements. Drops the size of the sparse set by 3 usizes (24 bytes on 64-bit systems) ## Followup ~~After #4809, Archetype's component SparseSet should be replaced with it.~~ This has been done. --- ## Changelog Removed: `Table::component_capacity` ## Migration Guide `Table::component_capacity()` has been removed as Tables do not support adding/removing columns after construction. Co-authored-by: Carter Anderson <mcanders1@gmail.com>

bors · 2022-11-15T22:38:57Z

Pull request successfully merged into main.

Build succeeded:

# Objective Make core types in ECS smaller. The column sparse set in Tables is never updated after creation. ## Solution Create `ImmutableSparseSet` which removes the capacity fields in the backing vec's and the APIs for inserting or removing elements. Drops the size of the sparse set by 3 usizes (24 bytes on 64-bit systems) ## Followup ~~After bevyengine#4809, Archetype's component SparseSet should be replaced with it.~~ This has been done. --- ## Changelog Removed: `Table::component_capacity` ## Migration Guide `Table::component_capacity()` has been removed as Tables do not support adding/removing columns after construction. Co-authored-by: Carter Anderson <mcanders1@gmail.com>

@cart

## 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>

Immutable sparse sets for metadata storage

767753a

james7132 added A-ECS Entities, components, systems, and events C-Performance A change motivated by improving speed, memory usage or compile times M-Needs-Migration-Guide A breaking change to Bevy's public API that needs to be noted in a migration guide labels Jun 4, 2022

Fix tests

7e85fe6

Weibye added the S-Adopt-Me The original PR author has no intent to complete this work. Pick me up! label Aug 10, 2022

james7132 removed the S-Adopt-Me The original PR author has no intent to complete this work. Pick me up! label Sep 14, 2022