Checking how Tokio deals with too many receivers in a broadcast

tokiobroadcast/Cargo.lock

@@ -0,0 +1,138 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
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+]
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tokiobroadcast/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "tokiobroadcast"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+rand = "0.8.5"
+tokio = { version = "1.17.0", features = ["rt", "sync", "macros", "time"] }

tokiobroadcast/src/main.rs

@@ -0,0 +1,29 @@
+use tokio::sync::broadcast;
+
+#[tokio::main(flavor = "current_thread")]
+async fn main() {
+    let (tx, _) = broadcast::channel(1);
+
+    for i in 0..30000 {
+        let mut rx = tx.subscribe();
+        let _consumer = tokio::spawn(async move {
+            while let Ok(mess) = rx.recv().await {
+                println!("Consumer {}: {}", i, mess);
+            }
+            println!("Consumer {} is done", i);
+        });
+    }
+
+    let producer = tokio::spawn(async move {
+        // let mut rng = 3;
+        loop {
+            tx.send(42).expect("Failed to send!");
+            tokio::task::yield_now().await;
+            // rng += 17 % 200;
+            // let duration = tokio::time::Duration::from_millis(rng);
+            // tokio::time::sleep(duration).await;
+        }
+    });
+
+    let _ = producer.await;
+}