Optimize Schema.find

Signed-off-by: Edwin Török <[email protected]>

ocaml/database/db_cache_types.ml

@@ -175,7 +175,7 @@ module Row = struct
         else
           t
       )
-      t schema.Schema.Table.columns
+      t (Schema.ColumnMap.to_list schema.Schema.Table.columns)
 end
 
 module Table = struct

ocaml/database/schema.ml

@@ -98,14 +98,37 @@ module Column = struct
   [@@deriving sexp]
 end
 
+module ColumnMap = struct
+  module M = Map.Make (String)
+
+  type t = Column.t M.t * Column.t list
+
+  type compat = Column.t list [@@deriving sexp]
+
+  let of_list columns =
+    ( columns |> List.fold_left (fun acc c -> M.add c.Column.name c acc) M.empty
+    , columns
+    )
+
+  let to_list (_, lst) = lst
+
+  let t_of_sexp sexp = sexp |> compat_of_sexp |> of_list
+
+  let sexp_of_t (_, compat) = sexp_of_compat compat
+
+  let find_opt name (t, _) = M.find_opt name t
+end
+
 module Table = struct
-  type t = {name: string; columns: Column.t list; persistent: bool}
+  type t = {name: string; columns: ColumnMap.t; persistent: bool}
   [@@deriving sexp]
 
   let find name t =
-    try List.find (fun col -> col.Column.name = name) t.columns
-    with Not_found ->
-      raise (Db_exn.DBCache_NotFound ("missing column", t.name, name))
+    match ColumnMap.find_opt name t.columns with
+    | Some result ->
+        result
+    | None ->
+        raise (Db_exn.DBCache_NotFound ("missing column", t.name, name))
 end
 
 type relationship = OneToMany of string * string * string * string

ocaml/database/test_schemas.ml

@@ -103,14 +103,24 @@ let schema =
     {
       Schema.Table.name= "VM"
     ; columns=
-        [_ref; uuid; name_label; vbds; pp; name_description; tags; other_config]
+        Schema.ColumnMap.of_list
+          [
+            _ref
+          ; uuid
+          ; name_label
+          ; vbds
+          ; pp
+          ; name_description
+          ; tags
+          ; other_config
+          ]
     ; persistent= true
     }
   in
   let vbd_table =
     {
       Schema.Table.name= "VBD"
-    ; columns= [_ref; uuid; vm; type']
+    ; columns= Schema.ColumnMap.of_list [_ref; uuid; vm; type']
     ; persistent= true
     }
   in
@@ -140,10 +150,18 @@ let many_to_many =
   in
   let foo_column = {bar_column with Schema.Column.name= "foos"} in
   let foo_table =
-    {Schema.Table.name= "foo"; columns= [bar_column]; persistent= true}
+    {
+      Schema.Table.name= "foo"
+    ; columns= Schema.ColumnMap.of_list [bar_column]
+    ; persistent= true
+    }
   in
   let bar_table =
-    {Schema.Table.name= "bar"; columns= [foo_column]; persistent= true}
+    {
+      Schema.Table.name= "bar"
+    ; columns= Schema.ColumnMap.of_list [foo_column]
+    ; persistent= true
+    }
   in
   let database = {Schema.Database.tables= [foo_table; bar_table]} in
   let many_to_many =

ocaml/idl/datamodel_schema.ml

@@ -90,6 +90,7 @@ let of_datamodel () =
     ; columns=
         _ref
         :: List.map (column obj) (flatten_fields obj.Datamodel_types.contents [])
+        |> Schema.ColumnMap.of_list
     ; persistent=
         obj.Datamodel_types.persist = Datamodel_types.PersistEverything
     }