fix(latency): resolve message delivery slowness on restart and fresh

fix(latency): resolve message delivery slowness on restart and fresh

src/Socket/chats.ts

@@ -89,7 +89,8 @@ export const makeChatsSocket = (config: SocketConfig) => {
 		query,
 		signalRepository,
 		onUnexpectedError,
-		sendUnifiedSession
+		sendUnifiedSession,
+		skipOfflineBuffer: socketSkippedOfflineBuffer
 	} = sock
 
 	const getLIDForPN = signalRepository.lidMapping.getLIDForPN.bind(signalRepository.lidMapping)
@@ -1436,15 +1437,21 @@ export const makeChatsSocket = (config: SocketConfig) => {
 		logger.info('Connection is now AwaitingInitialSync, buffering events')
 		ev.buffer()
 
-		// On reconnections (accountSyncCounter > 0), app state was already synced in a previous
+		// On reconnections, app state was already synced in a previous session.
-		// session. Skip the 20s AwaitingInitialSync wait and go directly to Online so that
+		// Skip the AwaitingInitialSync wait and go directly to Online so that
-		// live incoming messages are not held in the buffer for up to 20-60 seconds.
+		// live incoming messages are not held in the buffer for up to 4 seconds.
-		// History messages that arrive later are still processed via processMessage regardless
+		//
-		// of the state machine phase (see the Syncing → Online path below).
+		// Two signals indicate a reconnect (either is sufficient):
-		const isReconnection = (authState.creds.accountSyncCounter ?? 0) > 0
+		// 1. accountSyncCounter > 0  — at least one full sync completed before
+		// 2. socketSkippedOfflineBuffer — socket.ts already determined this is a
+		//    reconnect (e.g. stale routingInfo was cleared) and skipped the offline
+		//    phase buffer. Keeping the second buffer active while the first was already
+		//    skipped would cause a mismatch: events flow immediately then stall for 4s.
+		const isReconnection = (authState.creds.accountSyncCounter ?? 0) > 0 || socketSkippedOfflineBuffer
 		if (isReconnection) {
 			logger.info(
-				'Reconnection detected (accountSyncCounter > 0), skipping AwaitingInitialSync wait. Transitioning to Online immediately.'
+				{ accountSyncCounter: authState.creds.accountSyncCounter, socketSkippedOfflineBuffer },
+				'Reconnection detected, skipping AwaitingInitialSync wait. Transitioning to Online immediately.'
 			)
 			blockedCollections.clear()
 			syncState = SyncState.Online
@@ -1472,12 +1479,15 @@ export const makeChatsSocket = (config: SocketConfig) => {
 			return
 		}
 
-		// perf(inbound-latency): reduced from 20s → 8s. On first connection we wait for the
+		// perf(inbound-latency): reduced from 20s → 8s → 4s. On first connection we wait for
-		// history-sync notification so that doAppStateSync runs before live messages are emitted.
+		// the history-sync notification so that doAppStateSync runs before live messages are
-		// If the notification does not arrive within 8s we stop waiting, go Online, and flush
+		// emitted.  If the notification does not arrive within 4s we stop waiting, go Online,
-		// so that any live message arriving after connection is never held more than ~8s.
+		// and flush so that any live message arriving after connection is never held more than 4s.
 		// History that arrives late is still processed via processMessage regardless of state.
-		logger.info('First connection, awaiting history sync notification with an 8s timeout.')
+		// This 4s timeout fires before the event-buffer's own adaptive safety timer
+		// (BAILEYS_BUFFER_TIMEOUT_MS defaults to 5s), ensuring the buffer cannot stall
+		// beyond 4s on a first connect regardless of event rate.
+		logger.info('First connection, awaiting history sync notification with a 4s timeout.')
 
 		if (awaitingSyncTimeout) {
 			clearTimeout(awaitingSyncTimeout)
@@ -1485,7 +1495,7 @@ export const makeChatsSocket = (config: SocketConfig) => {
 
 		awaitingSyncTimeout = setTimeout(() => {
 			if (syncState === SyncState.AwaitingInitialSync) {
-				logger.warn('Timeout in AwaitingInitialSync (8s), forcing state to Online and flushing buffer')
+				logger.warn('Timeout in AwaitingInitialSync (4s), forcing state to Online and flushing buffer')
 				syncState = SyncState.Online
 				ev.flush()
 
@@ -1495,7 +1505,7 @@ export const makeChatsSocket = (config: SocketConfig) => {
 				const accountSyncCounter = (authState.creds.accountSyncCounter || 0) + 1
 				ev.emit('creds.update', { accountSyncCounter })
 			}
-		}, 8_000)
+		}, 4_000)
 	})
 
 	// When an app state sync key arrives (myAppStateKeyId is set) and there are

src/Socket/socket.ts

@@ -1797,7 +1797,13 @@ export const makeSocket = (config: SocketConfig) => {
 		/** Update server time offset (call when receiving server timestamps) */
 		updateServerTimeOffset: (serverTime: string | number) => {
 			unifiedSessionManager?.updateServerTimeOffset(serverTime)
-		}
+		},
+		/**
+		 * Whether the offline-phase buffer was skipped for this connection.
+		 * true  → this is a reconnect of an existing session (skip all sync waits in chats.ts too)
+		 * false → fresh QR-scan or first connection (normal sync flow applies)
+		 */
+		skipOfflineBuffer
 	}
 }
 

src/Utils/circuit-breaker.ts

@@ -709,6 +709,16 @@ export function createConnectionCircuitBreaker(customOptions?: Partial<CircuitBr
 		'network'
 	]
 
+	// Normal WS lifecycle status codes that must NEVER trip the query circuit breaker.
+	// These are transient events that happen on every reconnect and carry no information
+	// about persistent server-side failures.  The reconnection logic in makeSocket handles
+	// them independently.
+	const WS_LIFECYCLE_STATUS_CODES = new Set([
+		428, // connectionClosed
+		408, // connectionLost / timedOut
+		440, // connectionReplaced
+	])
+
 	return new CircuitBreaker({
 		name: 'connection-operations',
 		failureThreshold: 3,
@@ -720,6 +730,16 @@ export function createConnectionCircuitBreaker(customOptions?: Partial<CircuitBr
 			// accidentally matches the "socket" pattern below and causes a self-reinforcing loop
 			// where the breaker's own timeouts keep tripping the breaker. Exclude them explicitly.
 			if (error instanceof CircuitTimeoutError) return false
+
+			// Exclude normal WS reconnect events (Connection Closed, Connection Lost, Timed Out, etc.).
+			// These are not server-side failures — they happen on every restart/redeploy and should
+			// never cause the circuit to open.  If we counted them, the 3 concurrent parallel
+			// post-login queries (sendPassiveIq, uploadPreKeysToServerIfRequired, digestKeyBundle) could all
+			// fail simultaneously when the WS drops, instantly opening the circuit and blocking
+			// profile-picture fetches and message delivery for the next 30 s.
+			const statusCode = (error as { output?: { statusCode?: number } })?.output?.statusCode
+			if (statusCode !== undefined && WS_LIFECYCLE_STATUS_CODES.has(statusCode)) return false
+
 			const message = error.message.toLowerCase()
 			const code = (error as NodeJS.ErrnoException).code?.toLowerCase() || ''
 			return connectionErrorPatterns.some(pattern => message.includes(pattern) || code.includes(pattern))