delayed probes

config.example.json

@@ -22,6 +22,8 @@
       "02abc123...@1.2.3.4:9735"
     ],
     "amount_msats": [1000, 10000, 100000, 1000000],
-    "timeout_sec": 60
+    "timeout_sec": 60,
+    "probe_delay_sec": 1,
+    "peer_delay_sec": 2
   }
 }

prober_config.json.example

@@ -5,5 +5,7 @@
     "037d8e050899fa0732fdd6fc1e0d5d8d685c2093932a7e10dc5e6fab8a34ed1c43"
   ],
   "probe_amount_msats": [1000, 10000000, 100000000, 500000000],
-  "probe_timeout_sec": 3
+  "probe_timeout_sec": 3,
+  "probe_delay_sec": 1,
+  "peer_delay_sec": 2
 }

src/cli.rs

@@ -42,6 +42,8 @@ pub(crate) struct ProbingConfig {
 	pub(crate) peers: Vec<String>,
 	pub(crate) amount_msats: Vec<u64>,
 	pub(crate) timeout_sec: u64,
+	pub(crate) probe_delay_sec: u64,
+	pub(crate) peer_delay_sec: u64,
 }
 
 pub(crate) struct LdkUserInfo {

src/config.rs

@@ -63,6 +63,10 @@ pub struct ProbingConfig {
 	pub amount_msats: Vec<u64>,
 	#[serde(default = "default_probe_timeout")]
 	pub timeout_sec: u64,
+	#[serde(default = "default_probe_delay")]
+	pub probe_delay_sec: u64,
+	#[serde(default = "default_peer_delay")]
+	pub peer_delay_sec: u64,
 }
 
 // Default functions
@@ -86,6 +90,14 @@ fn default_probe_timeout() -> u64 {
 	60
 }
 
+fn default_probe_delay() -> u64 {
+	1
+}
+
+fn default_peer_delay() -> u64 {
+	2
+}
+
 impl Default for RapidGossipSyncConfig {
 	fn default() -> Self {
 		Self { enabled: true, url: None, interval_hours: 6 }
@@ -177,6 +189,8 @@ impl NodeConfig {
 			peers: p.peers,
 			amount_msats: p.amount_msats,
 			timeout_sec: p.timeout_sec,
+			probe_delay_sec: p.probe_delay_sec,
+			peer_delay_sec: p.peer_delay_sec,
 		});
 		LdkUserInfo {
 			bitcoind_rpc_username: self.bitcoind.rpc_username,
@@ -225,7 +239,9 @@ pub fn print_config_help() {
     "interval_sec": 300,
     "peers": [],
     "amount_msats": [1000, 10000, 100000],
-    "timeout_sec": 60
+    "timeout_sec": 60,
+    "probe_delay_sec": 1,
+    "peer_delay_sec": 2
   }}
 }}"#
 	);

src/main.rs

@@ -1317,16 +1317,20 @@ async fn start_ldk() {
 			sorted_amounts.sort();
 
 			let probe_timeout = Duration::from_secs(probe_config.timeout_sec);
+			let probe_delay = Duration::from_secs(probe_config.probe_delay_sec);
+			let peer_delay = Duration::from_secs(probe_config.peer_delay_sec);
 
 			// Log startup configuration
 			lightning::log_info!(
 				&*probing_logger,
-				"Probing started: {} peers, {} amounts {:?} msat, interval={}s, timeout={}s",
+				"Probing started: {} peers, {} amounts {:?} msat, interval={}s, timeout={}s, probe_delay={}s, peer_delay={}s",
 				probe_config.peers.len(),
 				sorted_amounts.len(),
 				sorted_amounts,
 				probe_config.interval_sec,
-				probe_config.timeout_sec
+				probe_config.timeout_sec,
+				probe_config.probe_delay_sec,
+				probe_config.peer_delay_sec
 			);
 
 			tokio::spawn(async move {
@@ -1336,7 +1340,8 @@ async fn start_ldk() {
 					interval.tick().await;
 
 					// Probe each peer with amounts from smallest to largest
-					for peer in &probe_config.peers {
+					let peer_count = probe_config.peers.len();
+					for (peer_idx, peer) in probe_config.peers.iter().enumerate() {
 						let peer_short = truncate_pubkey(peer);
 						'amounts: for &amount in &sorted_amounts {
 							// Send the probe and get the payment hash
@@ -1373,7 +1378,8 @@ async fn start_ldk() {
 											amount,
 											hash
 										);
-										// Probe succeeded, continue to next amount
+										// Probe succeeded, sleep before next amount
+										tokio::time::sleep(probe_delay).await;
 									},
 									Ok(Ok(ProbeOutcome::Failed)) => {
 										lightning::log_warn!(
@@ -1383,6 +1389,7 @@ async fn start_ldk() {
 											amount,
 											hash
 										);
+										tokio::time::sleep(probe_delay).await;
 										break 'amounts;
 									},
 									Ok(Err(_)) => {
@@ -1393,6 +1400,7 @@ async fn start_ldk() {
 											amount,
 											hash
 										);
+										tokio::time::sleep(probe_delay).await;
 										break 'amounts;
 									},
 									Err(_) => {
@@ -1409,6 +1417,7 @@ async fn start_ldk() {
 											.unwrap()
 											.pending_probes
 											.remove(&hash);
+										tokio::time::sleep(probe_delay).await;
 										break 'amounts;
 									},
 								}
@@ -1419,9 +1428,15 @@ async fn start_ldk() {
 									peer_short,
 									amount
 								);
+								tokio::time::sleep(probe_delay).await;
 								break 'amounts;
 							}
 						}
+
+						// Sleep between peers (except after the last peer)
+						if peer_idx < peer_count - 1 {
+							tokio::time::sleep(peer_delay).await;
+						}
 					}
 				}
 			});