diff --git a/cluster/router/chain/invoker_cache.go b/cluster/router/chain/invoker_cache.go
index 9f96bddd4224645fc45f5919879f380076deb2f1..43cdfa50670f5f09666dbea10a2837d58cafd1b0 100644
--- a/cluster/router/chain/invoker_cache.go
+++ b/cluster/router/chain/invoker_cache.go
@@ -49,8 +49,8 @@ func BuildCache(invokers []protocol.Invoker) *InvokerCache {
 	return &InvokerCache{
 		invokers:  invokers,
 		bitmap:    utils.ToBitmap(invokers),
-		pools:     make(map[string]router.AddrPool),
-		metadatas: make(map[string]router.AddrMetadata),
+		pools:     make(map[string]router.AddrPool, 8),
+		metadatas: make(map[string]router.AddrMetadata, 8),
 	}
 }