diff --git a/db/tikvgc.go b/db/tikvgc.go
index 041330f1..df023928 100644
--- a/db/tikvgc.go
+++ b/db/tikvgc.go
@@ -20,6 +20,7 @@ const (
 	tikvGcTimeFormat = "20060102-15:04:05 -0700 MST"
 )
 
+// StartTikvGC start tikv gcwork
 func StartTikvGC(db *DB, tikvCfg *conf.TikvGC) {
 	ticker := time.Tick(tikvCfg.Interval)
 	uuid := UUID()