diff --git a/src/lib_storage/raw_store.ml b/src/lib_storage/raw_store.ml
index 0bb8dd982..2848ade29 100644
--- a/src/lib_storage/raw_store.ml
+++ b/src/lib_storage/raw_store.ml
@@ -204,13 +204,13 @@ let list_sub l pos len =
         else inner (h :: acc, pred n) t in
   inner ([], len) l
 
-let with_rw_cursor_lwt ?sync ?metasync ?flags ?name { dir ; parent } ~f =
+let with_rw_cursor_lwt ?nosync ?nometasync ?flags ?name { dir ; parent } ~f =
   let local_parent =
     match Lwt.get parent with
     | None -> None
     | Some (txn, _db, _cursor) -> Some txn in
   Lmdb.create_rw_txn
-    ?sync ?metasync ?parent:local_parent dir >>=? fun txn ->
+    ?nosync ?nometasync ?parent:local_parent dir >>=? fun txn ->
   Lmdb.opendb ?flags ?name txn >>=? fun db ->
   Lmdb.opencursor txn db >>=? fun cursor ->
   Lwt.with_value parent (Some (txn, db, cursor)) begin fun () ->
diff --git a/vendors/ocaml-lmdb/src/lmdb.ml b/vendors/ocaml-lmdb/src/lmdb.ml
index d309ee48b..9cbca4f39 100644
--- a/vendors/ocaml-lmdb/src/lmdb.ml
+++ b/vendors/ocaml-lmdb/src/lmdb.ml
@@ -344,8 +344,8 @@ let rawtxn_of_txn : type a. a txn -> rawtxn = function
 external txn_begin :
   t -> int -> rawtxn option -> (rawtxn, int) result = "stub_mdb_txn_begin"
 
-let create_rw_txn ?(sync=true) ?(metasync=true) ?parent t =
-  let flags = match sync, metasync with
+let create_rw_txn ?(nosync=false) ?(nometasync=false) ?parent t =
+  let flags = match nosync, nometasync with
     | true, true -> int_of_flags_env [NoSync; NoMetaSync]
     | true, false -> int_of_flag_env NoSync
     | false, true -> int_of_flag_env NoMetaSync
@@ -354,8 +354,8 @@ let create_rw_txn ?(sync=true) ?(metasync=true) ?parent t =
   | Error i -> Error (error_of_int i)
   | Ok tx -> Ok (Txn_rw tx)
 
-let create_ro_txn ?(sync=true) ?(metasync=true) ?parent t =
-  let flags = match sync, metasync with
+let create_ro_txn ?(nosync=false) ?(nometasync=false) ?parent t =
+  let flags = match nosync, nometasync with
     | true, true -> int_of_flags_env [RdOnly; NoSync; NoMetaSync]
     | true, false -> int_of_flags_env [RdOnly; NoSync]
     | false, true -> int_of_flags_env [RdOnly; NoMetaSync]
@@ -420,8 +420,8 @@ external db_drop :
 let db_drop txn dbi =
   return (db_drop (rawtxn_of_txn txn) dbi false) ()
 
-let with_ro_db ?sync ?metasync ?parent ?flags ?name t ~f =
-  create_ro_txn ?sync ?metasync ?parent t >>= fun txn ->
+let with_ro_db ?nosync ?nometasync ?parent ?flags ?name t ~f =
+  create_ro_txn ?nosync ?nometasync ?parent t >>= fun txn ->
   opendb ?flags ?name txn >>= fun db ->
   match f txn db with
   | exception exn ->
@@ -434,8 +434,8 @@ let with_ro_db ?sync ?metasync ?parent ?flags ?name t ~f =
       abort_txn txn ;
       Error err
 
-let with_rw_db ?sync ?metasync ?parent ?flags ?name t ~f =
-  create_rw_txn ?sync ?metasync ?parent t >>= fun txn ->
+let with_rw_db ?nosync ?nometasync ?parent ?flags ?name t ~f =
+  create_rw_txn ?nosync ?nometasync ?parent t >>= fun txn ->
   opendb ?flags ?name txn >>= fun db ->
   match f txn db with
   | exception exn ->
diff --git a/vendors/ocaml-lmdb/src/lmdb.mli b/vendors/ocaml-lmdb/src/lmdb.mli
index 6be369e1f..92e74fb81 100644
--- a/vendors/ocaml-lmdb/src/lmdb.mli
+++ b/vendors/ocaml-lmdb/src/lmdb.mli
@@ -112,11 +112,11 @@ val set_mapsize : t -> int64 -> (unit, error) result
 type _ txn
 
 val create_rw_txn :
-  ?sync:bool -> ?metasync:bool ->
+  ?nosync:bool -> ?nometasync:bool ->
   ?parent:rw txn -> t -> (rw txn, error) result
 
 val create_ro_txn :
-  ?sync:bool -> ?metasync:bool ->
+  ?nosync:bool -> ?nometasync:bool ->
   ?parent:_ txn -> t -> (ro txn, error) result
 
 val get_txn_id : _ txn -> int
@@ -147,13 +147,13 @@ val db_flags : _ txn -> db -> (flag_open list, error) result
 val db_drop : _ txn -> db -> (unit, error) result
 
 val with_ro_db :
-  ?sync:bool -> ?metasync:bool ->
+  ?nosync:bool -> ?nometasync:bool ->
   ?parent:_ txn -> ?flags:flag_open list ->
   ?name:string -> t -> f:(ro txn -> db -> ('a, error) result) ->
   ('a, error) result
 
 val with_rw_db :
-  ?sync:bool -> ?metasync:bool ->
+  ?nosync:bool -> ?nometasync:bool ->
   ?parent:rw txn -> ?flags:flag_open list ->
   ?name:string -> t -> f:(rw txn -> db -> ('a, error) result) ->
   ('a, error) result