cluster: Lower sync config log level (#4929)

close #4923

Signed-off-by: bufferflies <1045931706@qq.com>

server/cluster/cluster.go

@@ -319,9 +319,11 @@ func syncConfig(manager *config.StoreConfigManager, stores []*core.StoreInfo) bo
 		// it will try next store if the current store is failed.
 		address := netutil.ResolveLoopBackAddr(stores[index].GetStatusAddress(), stores[index].GetAddress())
 		if err := manager.ObserveConfig(address); err != nil {
-			log.Warn("sync store config failed, it will try next store", zap.Error(err))
+			storeSyncConfigEvent.WithLabelValues(address, "fail").Inc()
+			log.Debug("sync store config failed, it will try next store", zap.Error(err))
 			continue
 		}
+		storeSyncConfigEvent.WithLabelValues(address, "succ").Inc()
 		// it will only try one store.
 		return true
 	}

server/cluster/metrics.go

@@ -96,6 +96,14 @@ var (
 			Help:      "The current progress of corresponding action",
 		}, []string{"address", "store", "action"})
 
+	storeSyncConfigEvent = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: "pd",
+			Subsystem: "cluster",
+			Name:      "store_sync",
+			Help:      "The state of store sync config",
+		}, []string{"address", "state"})
+
 	storesETAGauge = prometheus.NewGaugeVec(
 		prometheus.GaugeOpts{
 			Namespace: "pd",
@@ -117,4 +125,5 @@ func init() {
 	prometheus.MustRegister(bucketEventCounter)
 	prometheus.MustRegister(storesProgressGauge)
 	prometheus.MustRegister(storesETAGauge)
+	prometheus.MustRegister(storeSyncConfigEvent)
 }