[dbwriter][multicore] no need for thread

Summary: Multicore doesn't need an extra thread+queue to serialise writes to the database, a mutex is sufficient and each worker thread does its own writes.

Reviewed By: martintrojer

Differential Revision:
D69656883

Privacy Context Container: L1208441

fbshipit-source-id: 6c2c9590ff585099d02aad9461ef0d01bb3455da

infer/src/base/DBWriterDomain.ml

@@ -7,80 +7,15 @@
 open! IStd
 module L = Logging
 
-(* a request equipped with fields necessary to implement client blocking until the request is completed. *)
-type request =
-  { command: DBWriterCommand.t
-  ; mutex: Error_checking_mutex.t
-  ; mutable completed_flag: bool
-  ; completed: Condition.t }
-
-let make_request command =
-  { command
-  ; mutex= Error_checking_mutex.create ()
-  ; completed_flag= false
-  ; completed= Condition.create () }
-
-
-let wait_for_completion request =
-  let rec wait_loop () =
-    if not request.completed_flag then (
-      Condition.wait request.completed request.mutex ;
-      wait_loop () )
-  in
-  Error_checking_mutex.critical_section request.mutex ~f:wait_loop
-
-
-let request_queue = Concurrent.Queue.create ()
-
-let rec server_loop () =
-  let request = Concurrent.Queue.dequeue request_queue in
-  let command = request.command in
-  ( try
-      DBWriterCommand.perform command ;
-      (* signal completion to client *)
-      Error_checking_mutex.critical_section request.mutex ~f:(fun () ->
-          request.completed_flag <- true ;
-          Condition.signal request.completed )
-    with exn ->
-      L.die InternalError "DBWriter thread crashed@\n%a@\n%s@." Exn.pp exn
-        (Printexc.get_backtrace ()) ) ;
-  match (command : DBWriterCommand.t) with
-  | Terminate ->
-      L.debug Analysis Quiet "Sqlite write daemon: terminating@." ;
-      ExecutionDuration.log ~prefix:"dbwriter.store_sql" Analysis !DBWriterCommand.store_sql_time
-  | _ ->
-      server_loop ()
-
-
-let domain_server () =
-  Config.set_gc_params () ;
-  Database.new_database_connections Primary ;
-  server_loop ()
-
-
-let send command =
-  let request = make_request command in
-  Concurrent.Queue.enqueue request request_queue ;
-  wait_for_completion request
-
-
-let dbwriter_domain = ref None
-
-let start () =
-  dbwriter_domain := Some (Domain.spawn domain_server) ;
-  send Start
-
-
-let terminate () =
-  send Terminate ;
-  Option.iter !dbwriter_domain ~f:Domain.join
-
+let dbwriter_command_mutex = Error_checking_mutex.create ()
 
 let perform cmd =
   match (cmd : DBWriterCommand.t) with
-  | Start ->
-      start ()
   | Terminate ->
-      terminate ()
+      L.debug Analysis Quiet "Sqlite write daemon: terminating@." ;
+      ExecutionDuration.log ~prefix:"dbwriter.store_sql" Analysis !DBWriterCommand.store_sql_time ;
+      Error_checking_mutex.critical_section dbwriter_command_mutex ~f:(fun () ->
+          DBWriterCommand.perform cmd )
   | _ ->
-      send cmd
+      Error_checking_mutex.critical_section dbwriter_command_mutex ~f:(fun () ->
+          DBWriterCommand.perform cmd )