diff --git a/flex/storages/rt_mutable_graph/mutable_property_fragment.cc b/flex/storages/rt_mutable_graph/mutable_property_fragment.cc
index 4fc437820046..1cb2c329efd5 100644
--- a/flex/storages/rt_mutable_graph/mutable_property_fragment.cc
+++ b/flex/storages/rt_mutable_graph/mutable_property_fragment.cc
@@ -191,12 +191,11 @@ void MutablePropertyFragment::Open(const std::string& work_dir,
           schema_.get_vertex_storage_strategies(v_label_name), true);
     }
 
+    // We will reserve the at least 4096 slots for each vertex label
     size_t vertex_capacity =
-        schema_.get_max_vnum(v_label_name);  // lf_indexers_[i].capacity();
-    if (build_empty_graph) {
+        std::max(lf_indexers_[i].capacity(), (size_t) 4096);
+    if (vertex_capacity >= lf_indexers_[i].size()) {
       lf_indexers_[i].reserve(vertex_capacity);
-    } else {
-      vertex_capacity = lf_indexers_[i].capacity();
     }
     vertex_data_[i].resize(vertex_capacity);
     vertex_capacities[i] = vertex_capacity;