Despawn and despawn_recursive benchmarks

benches/benches/bevy_ecs/world/despawn.rs

@@ -0,0 +1,32 @@
+use bevy_ecs::prelude::*;
+use criterion::Criterion;
+use glam::*;
+
+#[derive(Component)]
+struct A(Mat4);
+#[derive(Component)]
+struct B(Vec4);
+
+pub fn world_despawn(criterion: &mut Criterion) {
+    let mut group = criterion.benchmark_group("despawn_world");
+    group.warm_up_time(core::time::Duration::from_millis(500));
+    group.measurement_time(core::time::Duration::from_secs(4));
+
+    for entity_count in (0..5).map(|i| 10_u32.pow(i)) {
+        let mut world = World::default();
+        for _ in 0..entity_count {
+            world.spawn((A(Mat4::default()), B(Vec4::default())));
+        }
+
+        let ents = world.iter_entities().map(|e| e.id()).collect::<Vec<_>>();
+        group.bench_function(format!("{}_entities", entity_count), |bencher| {
+            bencher.iter(|| {
+                ents.iter().for_each(|e| {
+                    world.despawn(*e);
+                });
+            });
+        });
+    }
+
+    group.finish();
+}

benches/benches/bevy_ecs/world/despawn_recursive.rs

@@ -0,0 +1,33 @@
+use bevy_ecs::prelude::*;
+use bevy_hierarchy::despawn_with_children_recursive;
+use criterion::Criterion;
+use glam::*;
+
+#[derive(Component)]
+struct A(Mat4);
+#[derive(Component)]
+struct B(Vec4);
+
+pub fn world_despawn_recursive(criterion: &mut Criterion) {
+    let mut group = criterion.benchmark_group("despawn_world_recursive");
+    group.warm_up_time(core::time::Duration::from_millis(500));
+    group.measurement_time(core::time::Duration::from_secs(4));
+
+    for entity_count in (0..5).map(|i| 10_u32.pow(i)) {
+        let mut world = World::default();
+        for _ in 0..entity_count {
+            world.spawn((A(Mat4::default()), B(Vec4::default())));
+        }
+
+        let ents = world.iter_entities().map(|e| e.id()).collect::<Vec<_>>();
+        group.bench_function(format!("{}_entities", entity_count), |bencher| {
+            bencher.iter(|| {
+                ents.iter().for_each(|e| {
+                    despawn_with_children_recursive(&mut world, *e);
+                });
+            });
+        });
+    }
+
+    group.finish();
+}

benches/benches/bevy_ecs/world/mod.rs

@@ -3,6 +3,12 @@ use criterion::criterion_group;
 mod commands;
 use commands::*;
 
+mod despawn;
+use despawn::*;
+
+mod despawn_recursive;
+use despawn_recursive::*;
+
 mod spawn;
 use spawn::*;
 
@@ -28,6 +34,8 @@ criterion_group!(
     world_query_iter,
     world_query_for_each,
     world_spawn,
+    world_despawn,
+    world_despawn_recursive,
     query_get,
     query_get_many::<2>,
     query_get_many::<5>,