log errors from monitoring call

main.go

@@ -377,7 +377,12 @@ func cachedRender(rs *routeStats) http.HandlerFunc {
 func main() {
 	rs := newRouteStats()
 	done := make(chan struct{})
-	go monitor(done, rs)
+	go func() {
+		err := monitor(done, rs)
+		if err != nil {
+			log.Fatal(err)
+		}
+	}()
 	log.Fatal(http.ListenAndServe(":8080", cachedRender(rs)))
 }