From 951d13d76cdb077852c966f52b4db07d305cf950 Mon Sep 17 00:00:00 2001
From: Sudarsan Reddy <sreddy@cloudflare.com>
Date: Tue, 25 May 2021 18:07:06 +0100
Subject: [PATCH] TUN-4456: Replaced instances of Tick() with Ticker() in h2mux
 paths

time.Tick() does not get garbage collected because the channel
underneath never gets deleted and the underlying Ticker can never be
recovered by the garbage collector. We replace this with NewTicker() to
avoid this.
---
 connection/h2mux.go | 5 +++--
 h2mux/muxreader.go  | 5 +++--
 h2mux/muxwriter.go  | 5 +++--
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/connection/h2mux.go b/connection/h2mux.go
index b97208d3..cd91a67f 100644
--- a/connection/h2mux.go
+++ b/connection/h2mux.go
@@ -167,7 +167,8 @@ func (h *h2muxConnection) serveMuxer(ctx context.Context) error {
 }
 
 func (h *h2muxConnection) controlLoop(ctx context.Context, connectedFuse ConnectedFuse, isNamedTunnel bool) {
-	updateMetricsTickC := time.Tick(h.muxerConfig.MetricsUpdateFreq)
+	updateMetricsTicker := time.NewTicker(h.muxerConfig.MetricsUpdateFreq)
+	defer updateMetricsTicker.Stop()
 	var shutdownCompleted <-chan struct{}
 	for {
 		select {
@@ -191,7 +192,7 @@ func (h *h2muxConnection) controlLoop(ctx context.Context, connectedFuse Connect
 			// don't wait for shutdown to finish when context is closed, this is the hard termination path
 			return
 
-		case <-updateMetricsTickC:
+		case <-updateMetricsTicker.C:
 			h.observer.metrics.updateMuxerMetrics(h.connIndexStr, h.muxer.Metrics())
 		}
 	}
diff --git a/h2mux/muxreader.go b/h2mux/muxreader.go
index 2716508f..cf8d98f1 100644
--- a/h2mux/muxreader.go
+++ b/h2mux/muxreader.go
@@ -69,12 +69,13 @@ func (r *MuxReader) run(log *zerolog.Logger) error {
 
 	// routine to periodically update bytesRead
 	go func() {
-		tickC := time.Tick(updateFreq)
+		ticker := time.NewTicker(updateFreq)
+		defer ticker.Stop()
 		for {
 			select {
 			case <-r.abortChan:
 				return
-			case <-tickC:
+			case <-ticker.C:
 				r.metricsUpdater.updateInBoundBytes(r.bytesRead.Count())
 			}
 		}
diff --git a/h2mux/muxwriter.go b/h2mux/muxwriter.go
index 6956876e..c4d8fded 100644
--- a/h2mux/muxwriter.go
+++ b/h2mux/muxwriter.go
@@ -78,12 +78,13 @@ func (w *MuxWriter) run(log *zerolog.Logger) error {
 
 	// routine to periodically communicate bytesWrote
 	go func() {
-		tickC := time.Tick(updateFreq)
+		ticker := time.NewTicker(updateFreq)
+		defer ticker.Stop()
 		for {
 			select {
 			case <-w.abortChan:
 				return
-			case <-tickC:
+			case <-ticker.C:
 				w.metricsUpdater.updateOutBoundBytes(w.bytesWrote.Count())
 			}
 		}