Use AtomicU64 instead of u64 for the position field in Receiver

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "async-broadcast"
-version = "0.7.1"
+version = "0.8.0"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/smol-rs/async-broadcast"
 documentation = "https://docs.rs/async-broadcast"

benches/broadcast_bench.rs

@@ -2,7 +2,7 @@ use async_broadcast::broadcast;
 use criterion::{criterion_group, criterion_main, Criterion};
 use futures_lite::future::block_on;
 pub fn broadcast_and_recv(c: &mut Criterion) {
-    let (s, mut r1) = broadcast(1);
+    let (s, r1) = broadcast(1);
 
     let mut n = 0;
     c.bench_function("1 -> 1", |b| {
@@ -15,7 +15,7 @@ pub fn broadcast_and_recv(c: &mut Criterion) {
         })
     });
 
-    let mut r2 = r1.clone();
+    let r2 = r1.clone();
 
     c.bench_function("1 -> 2", |b| {
         b.iter(|| {
@@ -28,8 +28,8 @@ pub fn broadcast_and_recv(c: &mut Criterion) {
         })
     });
 
-    let mut r3 = r1.clone();
-    let mut r4 = r1.clone();
+    let r3 = r1.clone();
+    let r4 = r1.clone();
 
     c.bench_function("1 -> 4", |b| {
         b.iter(|| {
@@ -44,10 +44,10 @@ pub fn broadcast_and_recv(c: &mut Criterion) {
         })
     });
 
-    let mut r5 = r1.clone();
-    let mut r6 = r1.clone();
-    let mut r7 = r1.clone();
-    let mut r8 = r1.clone();
+    let r5 = r1.clone();
+    let r6 = r1.clone();
+    let r7 = r1.clone();
+    let r8 = r1.clone();
 
     c.bench_function("1 -> 8", |b| {
         b.iter(|| {
@@ -65,6 +65,40 @@ pub fn broadcast_and_recv(c: &mut Criterion) {
             })
         })
     });
+
+    let r9 = r1.clone();
+    let r10 = r1.clone();
+    let r11 = r1.clone();
+    let r12 = r1.clone();
+    let r13 = r1.clone();
+    let r14 = r1.clone();
+    let r15 = r1.clone();
+    let r16 = r1.clone();
+
+    c.bench_function("1 -> 16", |b| {
+        b.iter(|| {
+            block_on(async {
+                s.broadcast(n).await.unwrap();
+                assert_eq!(r1.recv().await.unwrap(), n);
+                assert_eq!(r2.recv().await.unwrap(), n);
+                assert_eq!(r3.recv().await.unwrap(), n);
+                assert_eq!(r4.recv().await.unwrap(), n);
+                assert_eq!(r5.recv().await.unwrap(), n);
+                assert_eq!(r6.recv().await.unwrap(), n);
+                assert_eq!(r7.recv().await.unwrap(), n);
+                assert_eq!(r8.recv().await.unwrap(), n);
+                assert_eq!(r9.recv().await.unwrap(), n);
+                assert_eq!(r10.recv().await.unwrap(), n);
+                assert_eq!(r11.recv().await.unwrap(), n);
+                assert_eq!(r12.recv().await.unwrap(), n);
+                assert_eq!(r13.recv().await.unwrap(), n);
+                assert_eq!(r14.recv().await.unwrap(), n);
+                assert_eq!(r15.recv().await.unwrap(), n);
+                assert_eq!(r16.recv().await.unwrap(), n);
+                n += 1;
+            })
+        })
+    });
 }
 
 criterion_group!(benches, broadcast_and_recv);