From 3bec867ffabafae1a27cd427c3befbc1d4ae2f48 Mon Sep 17 00:00:00 2001
From: dignifiedquire <me@dignifiedquire.com>
Date: Thu, 9 Jan 2025 18:34:20 +0100
Subject: [PATCH] cleanup constants

---
 iroh-relay/src/protos/relay.rs  | 11 ++++++++++-
 iroh-relay/src/server/client.rs | 20 ++++++++++++--------
 2 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/iroh-relay/src/protos/relay.rs b/iroh-relay/src/protos/relay.rs
index 8c385f1a3c..86c3155582 100644
--- a/iroh-relay/src/protos/relay.rs
+++ b/iroh-relay/src/protos/relay.rs
@@ -41,8 +41,17 @@ const MAX_FRAME_SIZE: usize = 1024 * 1024;
 /// The Relay magic number, sent in the FrameType::ClientInfo frame upon initial connection.
 const MAGIC: &str = "RELAY🔑";
 
+/// Maximum time for a relay server to respond to a relay protocol ping.
 #[cfg(feature = "server")]
-pub(crate) const KEEP_ALIVE: Duration = Duration::from_secs(60);
+pub(crate) const PING_TIMEOUT: Duration = Duration::from_secs(5);
+
+/// Interval in which we ping the relay server to ensure the connection is alive.
+///
+/// The default QUIC max_idle_timeout is 30s, so setting that to half this time gives some
+/// chance of recovering.
+#[cfg(feature = "server")]
+pub(crate) const PING_INTERVAL: Duration = Duration::from_secs(15);
+
 /// The number of packets buffered for sending per client
 #[cfg(feature = "server")]
 pub(crate) const PER_CLIENT_SEND_QUEUE_DEPTH: usize = 512; //32;
diff --git a/iroh-relay/src/server/client.rs b/iroh-relay/src/server/client.rs
index b81c79b30c..cc9e0d4f1f 100644
--- a/iroh-relay/src/server/client.rs
+++ b/iroh-relay/src/server/client.rs
@@ -10,14 +10,17 @@ use futures_util::{SinkExt, Stream, StreamExt};
 use iroh_base::NodeId;
 use iroh_metrics::{inc, inc_by};
 use rand::Rng;
-use tokio::sync::mpsc::{self, error::TrySendError};
+use tokio::{
+    sync::mpsc::{self, error::TrySendError},
+    time::MissedTickBehavior,
+};
 use tokio_util::{sync::CancellationToken, task::AbortOnDropHandle};
 use tracing::{debug, error, instrument, trace, warn, Instrument};
 
 use crate::{
     protos::{
         disco,
-        relay::{write_frame, Frame, KEEP_ALIVE},
+        relay::{write_frame, Frame, PING_INTERVAL, PING_TIMEOUT},
     },
     server::{clients::Clients, metrics::Metrics, streams::RelayedStream, ClientRateLimit},
     PingTracker,
@@ -104,7 +107,7 @@ impl Client {
             node_id,
             connection_id,
             clients: clients.clone(),
-            ping_tracker: PingTracker::new(Duration::from_secs(5)),
+            ping_tracker: PingTracker::new(PING_TIMEOUT),
         };
 
         // start io loop
@@ -227,12 +230,13 @@ impl Actor {
         // Add some jitter to ping pong interactions, to avoid all pings being sent at the same time
         let next_interval = || {
             let random_secs = rand::rngs::OsRng.gen_range(1..=5);
-            Duration::from_secs(random_secs) + KEEP_ALIVE
+            Duration::from_secs(random_secs) + PING_INTERVAL
         };
 
-        let mut keep_alive = tokio::time::interval(next_interval());
+        let mut ping_interval = tokio::time::interval(next_interval());
         // ticks immediately
-        keep_alive.tick().await;
+        ping_interval.set_missed_tick_behavior(MissedTickBehavior::Delay);
+        ping_interval.tick().await;
 
         loop {
             tokio::select! {
@@ -267,10 +271,10 @@ impl Actor {
                     trace!("pong timed out");
                     break;
                 }
-                _ = keep_alive.tick() => {
+                _ = ping_interval.tick() => {
                     trace!("keep alive ping");
                     // new interval
-                    keep_alive.reset_after(next_interval());
+                    ping_interval.reset_after(next_interval());
                     let data = self.ping_tracker.new_ping();
                     self.write_frame(Frame::Ping { data }).await?;
                 }