some intermediate stuff

iroh/src/endpoint.rs

@@ -174,7 +174,9 @@ impl Builder {
         self.transport_config
             .default_path_max_idle_timeout(Some(PATH_MAX_IDLE_TIMEOUT));
         self.transport_config
-            .max_concurrent_multipath_paths(MAX_MULTIPATH_PATHS);
+            .max_concurrent_multipath_paths(MAX_MULTIPATH_PATHS + 1);
+        self.transport_config
+            .set_max_remote_nat_traversal_addresses(MAX_MULTIPATH_PATHS as u8);
 
         let static_config = StaticConfig {
             transport_config: Arc::new(self.transport_config),

iroh/src/magicsock.rs

@@ -94,7 +94,7 @@ pub(crate) const PATH_MAX_IDLE_TIMEOUT: Duration = Duration::from_millis(6500);
 /// Maximum number of concurrent QUIC multipath paths per connection.
 ///
 /// Pretty arbitrary and high right now.
-pub(crate) const MAX_MULTIPATH_PATHS: u32 = 16;
+pub(crate) const MAX_MULTIPATH_PATHS: u32 = 12;
 
 /// Error returned when the endpoint state actor stopped while waiting for a reply.
 #[stack_error(add_meta, derive)]

iroh/src/magicsock/remote_map/remote_state.rs

@@ -587,13 +587,12 @@ impl RemoteStateActor {
             trace!("not holepunching: no client connection");
             return;
         };
-        // TODO: these are the local addresses, so this will be very sad.
-        let Ok(remote_candidates) = conn
-            .get_remote_nat_traversal_addresses()
-            .and_then(|addrs| Ok(BTreeSet::from_iter(addrs)))
-        else {
-            warn!("boo");
-            return;
+        let remote_candidates = match conn.get_remote_nat_traversal_addresses() {
+            Ok(addrs) => BTreeSet::from_iter(addrs),
+            Err(err) => {
+                warn!("failed to get nat candidate addresses: {err:#}");
+                return;
+            }
         };
         // let remote_candidates = BTreeSet::from_iter(conn.get_nat_traversal_addresses());
         let local_candidates: BTreeSet<SocketAddr> = self
@@ -656,9 +655,8 @@ impl RemoteStateActor {
                     remote_candidates: BTreeSet::from_iter(remote_candidates),
                 });
             }
-            Err(_) => {
-                // TODO: log error
-                warn!("failed to initiate NAT traversal");
+            Err(err) => {
+                warn!("failed to initiate NAT traversal {err:#}");
             }
         }
     }

iroh/src/magicsock/remote_map/remote_state/path_state.rs

@@ -81,11 +81,6 @@ impl RemotePathState {
         self.emit_pending_resolve_requests(result.err());
     }
 
-    /// Returns an iterator over all paths and their state.
-    pub(super) fn iter(&self) -> impl Iterator<Item = (&transports::Addr, &PathState)> {
-        self.paths.iter()
-    }
-
     /// Returns an iterator over the addresses of all paths.
     pub(super) fn addrs(&self) -> impl Iterator<Item = &transports::Addr> {
         self.paths.keys()