best effort timestamp send

quinn-proto/src/connection/mod.rs

@@ -3304,6 +3304,11 @@ impl Connection {
             buf,
         );
 
+        if let Some(ts) = space.pending_acks.receiver_timestamps_as_mut() {
+            // Best effort / one try to send the timestamps to the peer.
+            ts.clear();
+        }
+
         stats.frame_tx.acks += 1;
     }
 

quinn-proto/src/connection/receiver_timestamps.rs

@@ -61,6 +61,11 @@ impl ReceiverTimestamps {
         });
     }
 
+    pub(crate) fn clear(&mut self) {
+        self.data.clear();
+    }
+
+    #[allow(dead_code)]
     pub(crate) fn subtract_below(&mut self, packet_number: u64) {
         if self.data.is_empty() {
             return;

quinn-proto/src/connection/spaces.rs

@@ -774,10 +774,6 @@ impl PendingAcks {
     /// Remove ACKs of packets numbered at or below `max` from the set of pending ACKs
     pub(super) fn subtract_below(&mut self, max: u64) {
         self.ranges.remove(0..(max + 1));
-
-        if let Some(v) = self.receiver_timestamps.as_mut() {
-            v.subtract_below(max);
-        }
     }
 
     /// Returns the set of currently pending ACK ranges