diff --git a/arcane/src/arcane/mesh/ItemInternalMap.h b/arcane/src/arcane/mesh/ItemInternalMap.h
index 03d36fcc9..f782d2653 100644
--- a/arcane/src/arcane/mesh/ItemInternalMap.h
+++ b/arcane/src/arcane/mesh/ItemInternalMap.h
@@ -153,9 +153,18 @@ class ARCANE_MESH_EXPORT ItemInternalMap
     return (m_new_impl.find(key) != m_new_impl.end());
   }
 
-  //! Resizes the hash table
-  void resize([[maybe_unused]] Int32 new_size, [[maybe_unused]] bool use_prime = false)
+  /*!
+   * \brief Makes room for \a new_size entries.
+   *
+   * Called before a batch of insertions by a family that knows how many items it
+   * is about to add, so that the table is sized once instead of growing by
+   * doubling and rehashing at each step. \a use_prime belonged to the previous
+   * implementation and is ignored.
+   */
+  void resize(Int32 new_size, [[maybe_unused]] bool use_prime = false)
   {
+    if (new_size > 0)
+      m_new_impl.reserve(static_cast<uint64_t>(new_size), false);
   }
 
   /*!
diff --git a/arcane/src/arcane/std/CartesianMeshGenerator.cc b/arcane/src/arcane/std/CartesianMeshGenerator.cc
index f391f4d13..b5ab53fb8 100644
--- a/arcane/src/arcane/std/CartesianMeshGenerator.cc
+++ b/arcane/src/arcane/std/CartesianMeshGenerator.cc
@@ -660,7 +660,11 @@ generateMesh()
 
   // Création hash-table des noeuds et préparation de leurs uid
   UniqueArray<Int64> nodes_unique_id(CheckedConvert::toInteger(own_nb_node_xyz));
-  HashTableMapT<Int64, NodeInfo> nodes_infos(CheckedConvert::toInteger(own_nb_node_xyz), true);
+  // The size of a HashTableMapT is a number of buckets and not a number of
+  // entries: it rehashes as soon as its count passes 0.85 * nb_bucket, so the
+  // table is sized for the load factor and holds every node without rehashing.
+  const Int64 wanted_bucket = static_cast<Int64>(own_nb_node_xyz / 0.85) + 1;
+  HashTableMapT<Int64, NodeInfo> nodes_infos(CheckedConvert::toInteger(wanted_bucket), true);
 
   // Calcule des infos blocs et des offset associés à tous les sub_domain_id
   IntegerUniqueArray sd_x_ibl, sd_x_obl; // Numéro et offset dans le bloc