sent hashes elsewhere measured

1 files changed, 14 insertions, 6 deletions

diff --git a/src/simtest/bench.rs b/src/simtest/bench.rs
index 6e216a9..da8e322 100644
--- a/src/simtest/bench.rs
+++ b/src/simtest/bench.rs
@@ -666,23 +666,31 @@ async fn trees(out: &mut String, nodes: &[AppState], net: &crate::transport::sim
 /// How many changes each session counts as sent to its peer (`SyncSession::sent_hashes_len`),
 /// after the workload: the most, and on average. Kept until the peer's next message
 /// says it has them; a session whose peer never sends one (along a tree, with one
-/// writer) keeps all.
+/// writer) keeps all. And of those, how many because another parent brings them
+/// (`SyncSession::known_to_peer`): a session with a neighbour we count as covered.
 async fn sent_kept(out: &mut String, nodes: &[AppState]) {
-    let mut most = 0;
-    let mut sum = 0;
+    let (mut most, mut sum) = (0, 0);
+    let (mut most_elsewhere, mut sum_elsewhere) = (0, 0);
     let mut sessions = 0;
     for node in nodes {
         for (_, peer_state) in node.peers_snapshot().await {
-            let kept = peer_state.lock().await.sync.sent_hashes_len();
+            let peer_state = peer_state.lock().await;
+            let kept = peer_state.sync.sent_hashes_len();
+            let elsewhere = peer_state.sync.sent_known_elsewhere_len();
             most = most.max(kept);
             sum += kept;
+            most_elsewhere = most_elsewhere.max(elsewhere);
+            sum_elsewhere += elsewhere;
             sessions += 1;
         }
     }
+    let sessions = f64::from(sessions.max(1));
     let _ = writeln!(
         out,
-        "    changes counted as sent, per session: {most} at most, {:.1} on average",
-        sum as f64 / f64::from(sessions.max(1)),
+        "    changes counted as sent, per session: {most} at most, {:.1} on average; \
+         of those, because another parent brings them: {most_elsewhere} at most, {:.1} on average",
+        sum as f64 / sessions,
+        sum_elsewhere as f64 / sessions,
     );
 }