open up to 3 s2s outgoing connection per domain pair

SVN Revision: 928

1 files changed, 71 insertions, 50 deletions

diff --git a/src/ejabberd_s2s.erl b/src/ejabberd_s2s.erl
index c9e40efbc..e20870272 100644
--- a/src/ejabberd_s2s.erl
+++ b/src/ejabberd_s2s.erl
@@ -3,12 +3,12 @@
 %%% Author  : Alexey Shchepin <alexey@sevcom.net>
 %%% Purpose : S2S connections manager
 %%% Created :  7 Dec 2002 by Alexey Shchepin <alexey@sevcom.net>
-%%% Id      : $Id$
+%%% Id      : $Id: ejabberd_s2s.erl 820 2007-07-19 21:17:13Z mremond $
 %%%----------------------------------------------------------------------
 
 -module(ejabberd_s2s).
 -author('alexey@sevcom.net').
--vsn('$Revision$ ').
+-vsn('$Revision: 820 $ ').
 
 -behaviour(gen_server).
 
@@ -16,9 +16,8 @@
 -export([start_link/0,
 	 route/3,
 	 have_connection/1,
-	 get_key/1,
+	 has_key/2,
 	 try_register/1,
-	 remove_connection/1,
 	 remove_connection/3,
 	 dirty_get_connections/0,
 	 allow_host/2,
@@ -55,14 +54,9 @@ route(From, To, Packet) ->
 	    ok
     end.
 
-remove_connection(FromTo) ->
-    F = fun() ->
-		mnesia:delete({s2s, FromTo})
-	end,
-    mnesia:transaction(F).
-
 remove_connection(FromTo, Pid, Key) ->
-    case catch mnesia:dirty_read(s2s, FromTo) of
+    ?ERROR_MSG("XXXXXXXXXXX ~p~n", [{FromTo, Pid, Key}]),
+    case catch mnesia:dirty_match_object(s2s, {s2s, FromTo, Pid, '_'}) of
 	[#s2s{pid = Pid, key = Key}] ->
 	    F = fun() ->
 			mnesia:delete_object(#s2s{fromto = FromTo,
@@ -82,23 +76,27 @@ have_connection(FromTo) ->
 	    false
     end.
 
-get_key(FromTo) ->
-    case catch mnesia:dirty_read(s2s, FromTo) of
-	[E] ->
-	    E#s2s.key;
+has_key(FromTo, Key) ->
+    case mnesia:dirty_select(s2s,
+			     [{#s2s{fromto = FromTo, key = Key, _ = '_'},
+			       [],
+			       ['$_']}]) of
+	[] ->
+	    false;
 	_ ->
-	    error
+	    true
     end.
 
 try_register(FromTo) ->
     Key = randoms:get_string(),
+    Max_S2S_Connexions_Number = 3,
     F = fun() ->
 		case mnesia:read({s2s, FromTo}) of
-		    [] ->
-			mnesia:write(#s2s{fromto = FromTo,
-					  pid = self(),
-					  key = Key}),
-			{key, Key};
+		    L when length(L) < Max_S2S_Connexions_Number ->
+			   mnesia:write(#s2s{fromto = FromTo,
+					     pid = self(),
+					     key = Key}),
+			   {key, Key};
 		    _ ->
 			false
 		end
@@ -126,9 +124,10 @@ dirty_get_connections() ->
 %%--------------------------------------------------------------------
 init([]) ->
     update_tables(),
-    mnesia:create_table(s2s, [{ram_copies, [node()]},
+    mnesia:create_table(s2s, [{ram_copies, [node()]}, {type, bag},
 			      {attributes, record_info(fields, s2s)}]),
     mnesia:add_table_copy(s2s, node(), ram_copies),
+    mnesia:add_table_index(s2s, key),
     mnesia:subscribe(system),
     ejabberd_ctl:register_commands(
       [{"incoming-s2s-number", "print number of incoming s2s connections on the node"},
@@ -224,7 +223,7 @@ do_route(From, To, Packet) ->
 						  Attrs),
 	    send_element(Pid, {xmlelement, Name, NewAttrs, Els}),
 	    ok;
-	{aborted, Reason} ->
+	{aborted, _Reason} ->
 	    case xml:get_tag_attr_s("type", Packet) of
 		"error" -> ok;
 		"result" -> ok;
@@ -240,6 +239,8 @@ find_connection(From, To) ->
     #jid{lserver = MyServer} = From,
     #jid{lserver = Server} = To,
     FromTo = {MyServer, Server},
+    Max_S2S_Connexions_Number = 3,
+    ?ERROR_MSG("XXX Finding connection for ~p~n", [FromTo]),
     case catch mnesia:dirty_read(s2s, FromTo) of
 	{'EXIT', Reason} ->
 	    {aborted, Reason};
@@ -250,36 +251,49 @@ find_connection(From, To) ->
 	    case {is_service(From, To),
 		  allow_host(MyServer, Server)} of
 		{false, true} ->
-		    ?DEBUG("starting new s2s connection~n", []),
-		    Key = randoms:get_string(),
-		    {ok, Pid} = ejabberd_s2s_out:start(
-				  MyServer, Server, {new, Key}),
-		    F = fun() ->
-				case mnesia:read({s2s, FromTo}) of
-				    [El] ->
-					El#s2s.pid;
-				    [] ->
-					mnesia:write(#s2s{fromto = FromTo,
-							  pid = Pid,
-							  key = Key}),
-					Pid
-				end
-			end,
-		    TRes = mnesia:transaction(F),
-		    case TRes of
-			{atomic, Pid} ->
-			    ejabberd_s2s_out:start_connection(Pid);
-			_ ->
-			    ejabberd_s2s_out:stop_connection(Pid)
-		    end,
-		    TRes;
+		    new_connection(MyServer, Server, From, FromTo, Max_S2S_Connexions_Number);
 		_ ->
 		    {aborted, error}
 	    end;
-	[El] ->
-	    {atomic, El#s2s.pid}
+	L when is_list(L) , length(L) < Max_S2S_Connexions_Number ->
+	    %% We establish another connection for this pair.
+	    new_connection(MyServer, Server, From, FromTo, Max_S2S_Connexions_Number);
+	L when is_list(L) ->
+	    %% We choose a connexion from the pool of opened ones.
+	    {atomic, choose_connection(From, L)}
     end.
 
+choose_connection(From, Connections) ->
+    El = lists:nth(erlang:phash(From, length(Connections)), Connections),
+    %El = lists:nth(random:uniform(length(Connections)), Connections),
+    ?ERROR_MSG("XXX using ejabberd_s2s_out ~p~n", [El#s2s.pid]),
+    El#s2s.pid.
+
+new_connection(MyServer, Server, From, FromTo, Max_S2S_Connexions_Number) ->
+    Key = randoms:get_string(),
+    {ok, Pid} = ejabberd_s2s_out:start(
+		  MyServer, Server, {new, Key}),
+    F = fun() ->
+		case mnesia:read({s2s, FromTo}) of
+		    L when length(L) < Max_S2S_Connexions_Number ->
+			mnesia:write(#s2s{fromto = FromTo,
+					  pid = Pid,
+					  key = Key}),
+			?ERROR_MSG("XXX new s2s connection started ~p~n", [Pid]),
+			Pid;
+		    L ->
+			choose_connection(From, L)
+		end
+	end,
+    TRes = mnesia:transaction(F),
+    case TRes of
+	{atomic, Pid} ->
+	    ejabberd_s2s_out:start_connection(Pid);
+	_ ->
+	    ejabberd_s2s_out:stop_connection(Pid)
+    end,
+    TRes.
+
 
 %%--------------------------------------------------------------------
 %% Function: is_service(From, To) -> true | false
@@ -321,6 +335,15 @@ ctl_process(Val, _Args) ->
     Val.
 
 update_tables() ->
+    case catch mnesia:table_info(s2s, type) of
+	bag ->
+	    ok;
+	{'EXIT', _} ->
+	    ok;
+	_ ->
+	    % XXX TODO convert it ?
+	    mnesia:delete_table(s2s)
+    end,
     case catch mnesia:table_info(s2s, attributes) of
 	[fromto, node, key] ->
 	    mnesia:transform_table(s2s, ignore, [fromto, pid, key]),
@@ -349,5 +372,3 @@ allow_host(MyServer, S2SHost) ->
 		_ -> true %% The default s2s policy is allow
 	    end
     end.
-    
-