From cb8b4aa49f2e5f956fe74adb515af182d415658c Mon Sep 17 00:00:00 2001
From: Mauricio Fernandez <mfp@acm.org>
Date: Sat, 13 Nov 2010 19:34:31 +0100
Subject: [PATCH] Revert "Implemented -flush-wait-time option."

This reverts commit 768adfc57cdabc28f0999b176c59961c9b60e101.
---
 mq_sqlite_persistence.ml  | 45 +++++++++++----------------------------
 mq_sqlite_persistence.mli |  5 +----
 ocamlmq.ml                |  6 +-----
 3 files changed, 15 insertions(+), 41 deletions(-)

diff --git a/mq_sqlite_persistence.ml b/mq_sqlite_persistence.ml
index 9680e54..db59959 100644
--- a/mq_sqlite_persistence.ml
+++ b/mq_sqlite_persistence.ml
@@ -23,8 +23,6 @@ type t = {
   mutable flush_alarm : unit Lwt.u;
   max_msgs_in_mem : int;
   mutable unacks : SSET.t;
-  flush_wait_time : float;
-  mutable flush_finished_signal : unit Lwt.t;
 }
 
 let count_unmaterialized_pending_acks db =
@@ -111,37 +109,24 @@ let unack db msg_id =
       sqlc"UPDATE ocamlmq_msgs SET ack_pending = 0 WHERE msg_id = %s"
       msg_id
 
-let make
-      ?(max_msgs_in_mem = max_int)
-      ?(flush_period = 1.0)
-      ?(flush_wait_time = 0.)
-      file =
+let make ?(max_msgs_in_mem = max_int) ?(flush_period = 1.0) file =
   let wait_flush, awaken_flush = Lwt.wait () in
-  let flush_finished, awaken_flush_finished = Lwt.wait () in
   let t =
     { db = Sqlexpr_sqlite.open_db file; in_mem = Hashtbl.create 13;
       in_mem_msgs = Hashtbl.create 13; ack_pending = SSET.empty;
       flush_alarm = awaken_flush;
       max_msgs_in_mem = max_msgs_in_mem;
       unacks = SSET.empty;
-      flush_finished_signal = flush_finished;
-      flush_wait_time = flush_wait_time;
     } in
   let flush_period = max flush_period 0.005 in
-  let wait_flush_time () =
-    if flush_wait_time > 0. then Lwt_unix.sleep flush_wait_time
-    else return () in
-  let rec loop_flush wait_flush awaken_flush_finished =
-      Lwt.choose [Lwt_unix.sleep flush_period; wait_flush >>= wait_flush_time] >>
-      begin
-        let wait, awaken = Lwt.wait () in
-        let ff, awaken_ff = Lwt.wait () in
-          flush t;
-          t.flush_alarm <- awaken;
-          t.flush_finished_signal <- ff;
-          Lwt.wakeup awaken_flush_finished ();
-          loop_flush wait awaken_ff
-      end in
+  let rec loop_flush wait_flush =
+    Lwt.choose [Lwt_unix.sleep flush_period; wait_flush] >>
+    begin
+      let wait, awaken = Lwt.wait () in
+        flush t;
+        t.flush_alarm <- awaken;
+        loop_flush wait
+    end in
   let rec loop_flush_unacks () =
     lwt () = Lwt_unix.sleep 0.1 in
       if not (SSET.is_empty t.unacks) then
@@ -153,7 +138,7 @@ let make
       loop_flush_unacks ()
   in
     ignore
-      (try_lwt loop_flush wait_flush awaken_flush_finished
+      (try_lwt loop_flush wait_flush
        with e -> puts "EXCEPTION IN FLUSHER: %s" (Printexc.to_string e);
                  return ());
     ignore
@@ -205,13 +190,9 @@ let do_save_msg t sent msg =
       in Hashtbl.add t.in_mem dest p
   end;
   Hashtbl.add t.in_mem_msgs msg.msg_id msg;
-  if Hashtbl.length t.in_mem_msgs < t.max_msgs_in_mem then
-    return ()
-  else begin
-    let wait = t.flush_finished_signal in
-      (try Lwt.wakeup t.flush_alarm (); with Invalid_argument _ -> ());
-      wait
-  end
+  if Hashtbl.length t.in_mem_msgs > t.max_msgs_in_mem then
+    Lwt.wakeup t.flush_alarm ();
+  return ()
 
 let save_msg t ?low_priority msg =
   do_save_msg t false msg
diff --git a/mq_sqlite_persistence.mli b/mq_sqlite_persistence.mli
index 4027f6c..99f2d4a 100644
--- a/mq_sqlite_persistence.mli
+++ b/mq_sqlite_persistence.mli
@@ -1,10 +1,7 @@
 
 include Mq_server.PERSISTENCE
 
-val make :
-  ?max_msgs_in_mem:int ->
-  ?flush_period:float ->
-  ?flush_wait_time:float -> string -> t
+val make : ?max_msgs_in_mem:int -> ?flush_period:float -> string -> t
 
 (* Used for testing *)
 val auto_check_db : Format.formatter -> bool
diff --git a/ocamlmq.ml b/ocamlmq.ml
index def3c77..208bf65 100644
--- a/ocamlmq.ml
+++ b/ocamlmq.ml
@@ -10,9 +10,8 @@ let debug = ref false
 let login = ref None
 let passcode = ref None
 let db = ref None
-let max_in_mem = ref 10000
+let max_in_mem = ref 100000
 let flush_period = ref 1.
-let flush_wait_ms = ref 0
 
 let params =
   Arg.align
@@ -24,8 +23,6 @@ let params =
         "N Flush to disk when there are more than N msgs in mem (default: 100000)";
       "-flush-period", Arg.Set_float flush_period,
         "DT Flush period in seconds (default: 1.0)";
-      "-flush-wait-time", Arg.Set_int flush_wait_ms,
-        "N Wait for N milliseconds before flushing (default 0)";
       "-debug", Arg.Set debug, " Write debug info to stderr.";
     ]
 
@@ -51,7 +48,6 @@ let () =
         Mq_sqlite_persistence.make
           ~max_msgs_in_mem:!max_in_mem
           ~flush_period:!flush_period
-          ~flush_wait_time:(float !flush_wait_ms *. 1e-3)
           (Option.default "ocamlmq.db" !db)
       in
         if !debug then eprintf "Connected to database.\n%!";