ssh remote: Only send a single FlushBufferedMessages (#19541)

Release Notes:

- N/A

---------

Co-authored-by: Bennet <bennet@zed.dev>

crates/remote/src/ssh_session.rs

@@ -1613,9 +1613,18 @@ impl ChannelClient {
     pub fn request<T: RequestMessage>(
         &self,
         payload: T,
+    ) -> impl 'static + Future<Output = Result<T::Response>> {
+        self.request_internal(payload, true)
+    }
+
+    fn request_internal<T: RequestMessage>(
+        &self,
+        payload: T,
+        use_buffer: bool,
     ) -> impl 'static + Future<Output = Result<T::Response>> {
         log::debug!("ssh request start. name:{}", T::NAME);
-        let response = self.request_dynamic(payload.into_envelope(0, None, None), T::NAME);
+        let response =
+            self.request_dynamic(payload.into_envelope(0, None, None), T::NAME, use_buffer);
         async move {
             let response = response.await?;
             log::debug!("ssh request finish. name:{}", T::NAME);
@@ -1627,7 +1636,9 @@ impl ChannelClient {
     pub async fn resync(&self, timeout: Duration) -> Result<()> {
         smol::future::or(
             async {
-                self.request(proto::FlushBufferedMessages {}).await?;
+                self.request_internal(proto::FlushBufferedMessages {}, false)
+                    .await?;
+
                 for envelope in self.buffer.lock().iter() {
                     self.outgoing_tx
                         .lock()
@@ -1663,10 +1674,11 @@ impl ChannelClient {
         self.send_dynamic(payload.into_envelope(0, None, None))
     }
 
-    pub fn request_dynamic(
+    fn request_dynamic(
         &self,
         mut envelope: proto::Envelope,
         type_name: &'static str,
+        use_buffer: bool,
     ) -> impl 'static + Future<Output = Result<proto::Envelope>> {
         envelope.id = self.next_message_id.fetch_add(1, SeqCst);
         let (tx, rx) = oneshot::channel();
@@ -1674,7 +1686,11 @@ impl ChannelClient {
         response_channels_lock.insert(MessageId(envelope.id), tx);
         drop(response_channels_lock);
 
-        let result = self.send_buffered(envelope);
+        let result = if use_buffer {
+            self.send_buffered(envelope)
+        } else {
+            self.send_unbuffered(envelope)
+        };
         async move {
             if let Err(error) = &result {
                 log::error!("failed to send message: {}", error);
@@ -1694,7 +1710,7 @@ impl ChannelClient {
         self.send_buffered(envelope)
     }
 
-    pub fn send_buffered(&self, mut envelope: proto::Envelope) -> Result<()> {
+    fn send_buffered(&self, mut envelope: proto::Envelope) -> Result<()> {
         envelope.ack_id = Some(self.max_received.load(SeqCst));
         self.buffer.lock().push_back(envelope.clone());
         // ignore errors on send (happen while we're reconnecting)
@@ -1702,6 +1718,12 @@ impl ChannelClient {
         self.outgoing_tx.lock().unbounded_send(envelope).ok();
         Ok(())
     }
+
+    fn send_unbuffered(&self, mut envelope: proto::Envelope) -> Result<()> {
+        envelope.ack_id = Some(self.max_received.load(SeqCst));
+        self.outgoing_tx.lock().unbounded_send(envelope).ok();
+        Ok(())
+    }
 }
 
 impl ProtoClient for ChannelClient {
@@ -1710,7 +1732,7 @@ impl ProtoClient for ChannelClient {
         envelope: proto::Envelope,
         request_type: &'static str,
     ) -> BoxFuture<'static, Result<proto::Envelope>> {
-        self.request_dynamic(envelope, request_type).boxed()
+        self.request_dynamic(envelope, request_type, true).boxed()
     }
 
     fn send(&self, envelope: proto::Envelope, _message_type: &'static str) -> Result<()> {