store: keep alive for etcd client (pingcap#14253)

Signed-off-by: qupeng <[email protected]>

Author: hicqu

store/tikv/kv.go

@@ -54,11 +54,15 @@ type Driver struct {
 }
 
 func createEtcdKV(addrs []string, tlsConfig *tls.Config) (*clientv3.Client, error) {
+	cfg := config.GetGlobalConfig()
 	cli, err := clientv3.New(clientv3.Config{
-		Endpoints:        addrs,
-		AutoSyncInterval: 30 * time.Second,
-		DialTimeout:      5 * time.Second,
-		TLS:              tlsConfig,
+		Endpoints:            addrs,
+		AutoSyncInterval:     30 * time.Second,
+		DialTimeout:          5 * time.Second,
+		TLS:                  tlsConfig,
+		DialKeepAliveTime:    time.Second * time.Duration(cfg.TiKVClient.GrpcKeepAliveTime),
+		DialKeepAliveTimeout: time.Second * time.Duration(cfg.TiKVClient.GrpcKeepAliveTimeout),
+		PermitWithoutStream:  true,
 	})
 	if err != nil {
 		return nil, errors.Trace(err)