diff --git a/src/share/vector_index/ob_plugin_vector_index_serialize.cpp b/src/share/vector_index/ob_plugin_vector_index_serialize.cpp
index 37b1e694a..f11df503d 100644
--- a/src/share/vector_index/ob_plugin_vector_index_serialize.cpp
+++ b/src/share/vector_index/ob_plugin_vector_index_serialize.cpp
@@ -261,6 +261,7 @@ int ObHNSWDeserializeCallback::operator()(char*& data, const int64_t data_size,
           str_iter->~ObTextStringIter();
           alloactor->free(str_iter);
           str_iter = nullptr;
+          alloactor->reuse();
         } else {
           ret = (str_iter->get_inner_ret() != OB_SUCCESS) ?
                 str_iter->get_inner_ret() : OB_INVALID_DATA;
@@ -269,6 +270,7 @@ int ObHNSWDeserializeCallback::operator()(char*& data, const int64_t data_size,
           str_iter->~ObTextStringIter();
           alloactor->free(str_iter);
           str_iter = nullptr;
+          alloactor->reuse();
         }
       }
       if (OB_SUCC(ret) && OB_ISNULL(str_iter)) {
diff --git a/src/share/vector_index/ob_plugin_vector_index_utils.cpp b/src/share/vector_index/ob_plugin_vector_index_utils.cpp
index 3700a8b04..08ed976dd 100644
--- a/src/share/vector_index/ob_plugin_vector_index_utils.cpp
+++ b/src/share/vector_index/ob_plugin_vector_index_utils.cpp
@@ -465,14 +465,15 @@ int ObPluginVectorIndexUtils::try_sync_snapshot_memdata(ObLSID &ls_id,
   } else if (OB_FAIL(adapter->try_init_mem_data(VIRT_SNAP))) {
     LOG_WARN("try init snap mem data failed.", K(ret));
   } else {
+    ObArenaAllocator tmp_allocator("VectorAdaptor", OB_MALLOC_NORMAL_BLOCK_SIZE, MTL_ID());
     ObHNSWDeserializeCallback::CbParam param;
     param.iter_ = snapshot_idx_iter;
-    param.allocator_ = &allocator;
+    param.allocator_ = &tmp_allocator;
 
     ObHNSWDeserializeCallback callback;
     ObIStreamBuf::Callback cb = callback;
     // ToDo: concurrency with weakread
-    ObVectorIndexSerializer index_seri(allocator);
+    ObVectorIndexSerializer index_seri(tmp_allocator);
     ObVectorIndexMemData *snap_memdata = adapter->get_snap_data_();
     if (OB_FAIL(adapter->try_init_mem_data(VIRT_SNAP))) {
       LOG_WARN("failed to init snapshot index.", K(ret));