soak neighbours and settled links

1 files changed, 29 insertions, 0 deletions

diff --git a/src/simtest/soak.rs b/src/simtest/soak.rs
index 2a9272a..6285e2c 100644
--- a/src/simtest/soak.rs
+++ b/src/simtest/soak.rs
@@ -117,6 +117,22 @@ const CHURN_WRITE_EVERY: Duration = Duration::from_millis(500);
 const AWAY_EVERY: Duration = Duration::from_secs(20);
 const AWAY_FOR: Duration = Duration::from_secs(15);
 const RESTART_EVERY: Duration = Duration::from_secs(120);
+/// How many neighbours each node has (`topology::our_neighbours`), `when`.
+fn neighbour_counts(out: &mut String, nodes: &[AppState], when: &str) {
+    use std::fmt::Write;
+    let counts: Vec<usize> = nodes
+        .iter()
+        .map(|node| crate::swarm::topology::our_neighbours(node).len())
+        .collect();
+    let _ = writeln!(
+        out,
+        "    neighbours {when}: {:.1} on average, {} to {}",
+        counts.iter().sum::<usize>() as f64 / counts.len().max(1) as f64,
+        counts.iter().min().copied().unwrap_or(0),
+        counts.iter().max().copied().unwrap_or(0),
+    );
+}
+
 /// How long the quiet phase at the end is watched.
 const CHURN_QUIET: Duration = Duration::from_secs(30);
 
@@ -304,6 +320,7 @@ async fn soak_with_churn() {
             .map_or("more than an hour".to_owned(), |ms| format!("{ms} ms")),
     );
     super::bench::sent_kept(&mut out, &nodes).await;
+    neighbour_counts(&mut out, &nodes, "at the end");
     // For PlumTree and HyParView: their links and views at the end (nothing otherwise).
     super::bench::eager_links(&mut out, &nodes, &sim.net);
     super::bench::active_views(&mut out, &nodes);
@@ -371,6 +388,18 @@ async fn soak_with_churn() {
             links.unreached, links.reached
         );
     }
+    // Again once the swarm had the quiet phase to settle in after the remake's switch:
+    // whether what the end shows is the switch's, or stays.
+    let mut out = String::new();
+    neighbour_counts(&mut out, &nodes, "after the quiet phase");
+    let mut links = String::new();
+    super::bench::eager_links(&mut links, &nodes, &sim.net);
+    super::bench::active_views(&mut links, &nodes);
+    if !links.is_empty() {
+        out.push_str("    after the quiet phase:\n");
+        out.push_str(&links);
+    }
+    print!("{out}");
 
     for (what, most) in [
         ("peers", peers),