James Liu 88b353c4b1 Reduce the use of atomics in the render phase (#7084) ... # Objective Speed up the render phase of rendering. An extension of #6885. `SystemState::get` increments the `World`'s change tick atomically every time it's called. This is notably more expensive than a unsynchronized increment, even without contention. It also updates the archetypes, even when there has been nothing to update when it's called repeatedly. ## Solution Piggyback off of #6885. Split `SystemState::validate_world_and_update_archetypes` into `SystemState::validate_world` and `SystemState::update_archetypes`, and make the later `pub`. Then create safe variants of `SystemState::get_unchecked_manual` that still validate the `World` but do not update archetypes and do not increment the change tick using `World::read_change_tick` and `World::change_tick`. Update `RenderCommandState` to call `SystemState::update_archetypes` in `Draw::prepare` and `SystemState::get_manual` in `Draw::draw`. ## Performance There's a slight perf benefit (~2%) for `main_opaque_pass_3d` on `many_foxes` (340.39 us -> 333.32 us)  ## Alternatives We can change `SystemState::get` to not increment the `World`'s change tick. Though this would still put updating the archetypes and an atomic read on the hot-path. --- ## Changelog Added: `SystemState::get_manual` Added: `SystemState::get_manual_mut` Added: `SystemState::update_archetypes`		2023-01-18 02:19:19 +00:00
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macros	Support storage buffers in derive AsBindGroup (#6129)	2023-01-09 18:50:55 +00:00
src	Reduce the use of atomics in the render phase (#7084)	2023-01-18 02:19:19 +00:00
Cargo.toml	Improve Color::hex performance (#6940)	2023-01-17 13:26:43 +00:00