[sql] disable compaction while merge results

Summary: Not sure if useful but seems sensible. It disappears at the top of the stack when we do merging in SQL.

Reviewed By: mbouaziz

Differential Revision: D5824131

fbshipit-source-id: fd64752

INSTALL.md

@@ -20,6 +20,7 @@ compile everything from source (see the end of this document).
 
 - opam 1.2.2 (instructions [here](https://opam.ocaml.org/doc/Install.html#OSX))
 - Python 2.7
+- sqlite
 - pkg-config
 - Java (only needed for the Java analysis)
 - cmake (only needed for the C/Objective-C analysis)
@@ -32,7 +33,7 @@ You can install some of these dependencies using
 [Homebrew](http://brew.sh/):
 
 ```sh
-brew install autoconf automake cmake opam pkg-config
+brew install autoconf automake cmake opam pkg-config sqlite
 brew cask install java
 ```
 

infer/src/backend/InferPrint.ml

@@ -962,15 +962,6 @@ module AnalysisResults = struct
       if List.is_empty Config.anon_args then load_specfiles () else List.rev Config.anon_args )
     else load_specfiles ()
 
-  (** apply [f] to [arg] with the gc compaction disabled during the execution *)
-  let apply_without_gc f arg =
-    let stat = Gc.get () in
-    let space_oh = stat.space_overhead in
-    Gc.set {stat with space_overhead= 10000} ;
-    let res = f arg in
-    Gc.set {stat with space_overhead= space_oh} ;
-    res
-
   (** Load .specs files in memory and return list of summaries *)
   let load_summaries_in_memory () : t =
     let summaries = ref [] in
@@ -981,7 +972,8 @@ module AnalysisResults = struct
       | Some summary
        -> summaries := (fname, summary) :: !summaries
     in
-    apply_without_gc (List.iter ~f:load_file) (spec_files_from_cmdline ()) ;
+    let do_load () = spec_files_from_cmdline () |> List.iter ~f:load_file in
+    Utils.without_gc ~f:do_load ;
     let summ_cmp (_, summ1) (_, summ2) =
       let n =
         SourceFile.compare summ1.Specs.attributes.ProcAttributes.loc.Location.file

infer/src/base/MergeResults.ml

@@ -26,7 +26,8 @@ let merge ~into db =
   let db_name = "db" in
   SqliteUtils.check_sqlite_error ~fatal:true ~log:"attaching db"
     (Sqlite3.exec into (Printf.sprintf "ATTACH '%s' AS %s" db db_name)) ;
-  merge_attributes_table ~into ~db_name ;
+  let do_merge () = merge_attributes_table ~into ~db_name in
+  Utils.without_gc ~f:do_merge ;
   SqliteUtils.check_sqlite_error ~fatal:true ~log:"detaching db"
     (Sqlite3.exec into (Printf.sprintf "DETACH %s" db_name)) ;
   ()

infer/src/base/Utils.ml

@@ -308,3 +308,11 @@ let rec rmtree name =
    -> Unix.unlink name
   | exception Unix.Unix_error (Unix.ENOENT, _, _)
    -> ()
+
+let without_gc ~f =
+  let stat = Gc.get () in
+  let space_oh = stat.space_overhead in
+  Gc.set {stat with space_overhead= 10000} ;
+  let res = f () in
+  Gc.set {stat with space_overhead= space_oh} ;
+  res

infer/src/base/Utils.mli

@@ -98,3 +98,6 @@ val rmtree : string -> unit
 val try_finally_swallow_timeout : f:(unit -> 'a) -> finally:(unit -> unit) -> 'a
 (** Calls [f] then [finally] even if [f] raised an exception. The original exception is reraised afterwards.
     Where possible use [SymOp.try_finally] to avoid swallowing timeouts. *)
+
+val without_gc : f:(unit -> unit) -> unit
+(** Call [f ()] with the gc compaction disabled during the execution *)