From 47d7118f040d9fa3fb098aeb04423ff008ce3ad8 Mon Sep 17 00:00:00 2001
From: Joe Ardent <code@ardent.nebcorp.com>
Date: Wed, 17 Sep 2025 14:08:54 -0700
Subject: [PATCH] just gossip to one non-self node 2x as often, better
 latencies, same msgs/op

---
 gg-broadcast/src/main.rs | 57 ++++++++++++++++------------------------
 1 file changed, 22 insertions(+), 35 deletions(-)

diff --git a/gg-broadcast/src/main.rs b/gg-broadcast/src/main.rs
index 3e25ab2..de48b16 100644
--- a/gg-broadcast/src/main.rs
+++ b/gg-broadcast/src/main.rs
@@ -18,7 +18,7 @@ fn main() {
 fn on_init(runner: &Runner) {
     let tx = runner.get_backdoor();
     thread::spawn(move || loop {
-        let millis = 50;
+        let millis = 25;
         thread::sleep(Duration::from_millis(millis));
         let body = Body::from_type("do_gossip");
         let msg = Message {
@@ -33,45 +33,30 @@ fn on_init(runner: &Runner) {
 struct BCaster {
     store: BTreeSet<i64>,
     gossips: HashMap<String, BTreeSet<i64>>,
-    neighbors: Vec<String>,
-    others: Vec<String>,
+    nodes: Vec<String>,
 }
 
 impl BCaster {
-    fn topology(&mut self, topology: HashMap<String, Vec<String>>, id: &str) {
-        self.neighbors = topology[id].clone();
-        self.neighbors.sort_unstable();
-        for node in topology.keys() {
-            if !(node == id || self.neighbors.binary_search(node).is_ok()) {
-                self.others.push(node.to_owned());
-            }
-        }
-    }
-
     fn gossip(&self, runner: &Runner) {
-        let mut rng = rand::thread_rng();
-        let neighbor = &self.neighbors[rng.gen_range(0..self.neighbors.len())];
-        let goss = if let Some(ngoss) = self.gossips.get(neighbor) {
-            self.store.difference(ngoss).copied().collect()
-        } else {
-            self.store.clone()
-        };
-        let goss: Vec<_> = goss.into_iter().collect();
-        let payload: Payload = [("goss".to_string(), goss.into())].into_iter().collect();
-        let body = Body::from_type("gossip").with_payload(payload);
-        runner.send(neighbor, body);
+        if self.nodes.is_empty() {
+            return;
+        }
 
-        // now the non-neighbor
-        let other = &self.others[rng.gen_range(0..self.others.len())];
-        let goss = if let Some(goss) = self.gossips.get(other) {
+        let mut rng = rand::thread_rng();
+        let dest = &self.nodes[rng.gen_range(0..self.nodes.len())];
+        let goss = if let Some(goss) = self.gossips.get(dest) {
             self.store.difference(goss).copied().collect()
         } else {
             self.store.clone()
         };
-        let goss: Vec<_> = goss.into_iter().collect();
-        let payload: Payload = [("goss".to_string(), goss.into())].into_iter().collect();
+        let payload: Payload = [(
+            "goss".to_string(),
+            goss.into_iter().collect::<Vec<_>>().into(),
+        )]
+        .into_iter()
+        .collect();
         let body = Body::from_type("gossip").with_payload(payload);
-        runner.send(other, body);
+        runner.send(dest, body);
     }
 }
 
@@ -103,11 +88,13 @@ impl Node for BCaster {
                 runner.reply(&req, body);
             }
             "topology" => {
-                let nid = runner.node_id();
-                let topology =
-                    serde_json::from_value(req.body.payload.get("topology").cloned().unwrap())
-                        .unwrap();
-                self.topology(topology, nid);
+                let nodes = runner
+                    .nodes()
+                    .iter()
+                    .filter(|&n| n.as_str() != runner.node_id())
+                    .cloned()
+                    .collect();
+                self.nodes = nodes;
                 let body = Body::from_type("topology_ok");
                 runner.reply(&req, body);
             }