reverting damien's latest commit until we can figure out why it's causing failures

git-svn-id: https://svn.apache.org/repos/asf/couchdb/trunk@918834 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 38 insertions, 37 deletions

diff --git a/src/couchdb/couch_query_servers.erl b/src/couchdb/couch_query_servers.erl
index 344ce8b2..3095b199 100644
--- a/src/couchdb/couch_query_servers.erl
+++ b/src/couchdb/couch_query_servers.erl
@@ -15,7 +15,7 @@
 
 -export([start_link/0]).
 
--export([init/1, terminate/2, handle_call/3, handle_cast/2, handle_info/2,code_change/3]).
+-export([init/1, terminate/2, handle_call/3, handle_cast/2, handle_info/2,code_change/3,stop/0]).
 -export([start_doc_map/2, map_docs/2, stop_doc_map/1]).
 -export([reduce/3, rereduce/3,validate_doc_update/5]).
 -export([filter_docs/5]).
@@ -38,6 +38,9 @@
 start_link() ->
     gen_server:start_link({local, couch_query_servers}, couch_query_servers, [], []).
 
+stop() ->
+    exit(whereis(couch_query_servers), normal).
+
 start_doc_map(Lang, Functions) ->
     Proc = get_os_process(Lang),
     lists:foreach(fun(FunctionSource) ->
@@ -216,18 +219,17 @@ init([]) ->
 
     ok = couch_config:register(
         fun("query_servers" ++ _, _) ->
-            supervisor:terminate_child(couch_secondary_services, query_servers),
-            supervisor:restart_child(couch_secondary_services, query_servers)
+            ?MODULE:stop()
         end),
     ok = couch_config:register(
         fun("native_query_servers" ++ _, _) ->
-            supervisor:terminate_child(couch_secondary_services, query_servers),
-            [supervisor:restart_child(couch_secondary_services, query_servers)]
+            ?MODULE:stop()
         end),
 
     Langs = ets:new(couch_query_server_langs, [set, private]),
     PidProcs = ets:new(couch_query_server_pid_langs, [set, private]),
     LangProcs = ets:new(couch_query_server_procs, [set, private]),
+    InUse = ets:new(couch_query_server_used, [set, private]),
     % 'query_servers' specifies an OS command-line to execute.
     lists:foreach(fun({Lang, Command}) ->
         true = ets:insert(Langs, {?l2b(Lang),
@@ -242,71 +244,75 @@ init([]) ->
     process_flag(trap_exit, true),
     {ok, {Langs, % Keyed by language name, value is {Mod,Func,Arg}
           PidProcs, % Keyed by PID, valus is a #proc record.
-          LangProcs % Keyed by language name, value is a #proc record
+          LangProcs, % Keyed by language name, value is a #proc record
+          InUse % Keyed by PID, value is #proc record.
           }}.
 
-terminate(_Reason, {_Langs, PidProcs, _LangProcs}) ->
-    [couch_util:shutdown_sync(P) || {P,_} <- ets:tab2list(PidProcs)],
+terminate(_Reason, _Server) ->
     ok.
 
-handle_call({get_proc, #doc{body={Props}}=DDoc, DDocKey}, _From, {Langs, PidProcs, LangProcs}=Server) ->
+handle_call({get_proc, #doc{body={Props}}=DDoc, DDocKey}, _From, {Langs, PidProcs, LangProcs, InUse}=Server) ->
     % Note to future self. Add max process limit.
     Lang = proplists:get_value(<<"language">>, Props, <<"javascript">>),    
     case ets:lookup(LangProcs, Lang) of
     [{Lang, [P|Rest]}] ->
         % find a proc in the set that has the DDoc
         case proc_with_ddoc(DDoc, DDocKey, [P|Rest]) of
-        {ok, Proc} ->
-            rem_from_list(LangProcs, Lang, Proc),
-            {reply, {ok, Proc, get_query_server_config()}, Server};
-        Error -> 
-            {reply, Error, Server}
-        end;
+            {ok, Proc} ->
+                % looks like the proc isn't getting dropped from the list.
+                % we need to change this to take a fun for equality checking
+                % so we can do a comparison on portnum
+                rem_from_list(LangProcs, Lang, Proc),
+                add_to_list(InUse, Lang, Proc),
+                {reply, {ok, Proc, get_query_server_config()}, Server};
+            Error -> 
+                {reply, Error, Server}
+            end;
     _ ->
         case (catch new_process(Langs, Lang)) of
         {ok, Proc} ->
             add_value(PidProcs, Proc#proc.pid, Proc),
             case proc_with_ddoc(DDoc, DDocKey, [Proc]) of
-            {ok, Proc2} ->
-                {reply, {ok, Proc2, get_query_server_config()}, Server};
-            Error -> 
-                {reply, Error, Server}
-            end;
+                {ok, Proc2} ->
+                    rem_from_list(LangProcs, Lang, Proc),
+                    add_to_list(InUse, Lang, Proc2),
+                    {reply, {ok, Proc2, get_query_server_config()}, Server};
+                Error -> 
+                    {reply, Error, Server}
+                end;
         Error ->
             {reply, Error, Server}
         end
     end;
-handle_call({get_proc, Lang}, _From, {Langs, PidProcs, LangProcs}=Server) ->
+handle_call({get_proc, Lang}, _From, {Langs, PidProcs, LangProcs, InUse}=Server) ->
     % Note to future self. Add max process limit.
     case ets:lookup(LangProcs, Lang) of
     [{Lang, [Proc|_]}] ->
+        add_value(PidProcs, Proc#proc.pid, Proc),
         rem_from_list(LangProcs, Lang, Proc),
+        add_to_list(InUse, Lang, Proc),
         {reply, {ok, Proc, get_query_server_config()}, Server};
     _ ->
         case (catch new_process(Langs, Lang)) of
         {ok, Proc} ->
             add_value(PidProcs, Proc#proc.pid, Proc),
+            add_to_list(InUse, Lang, Proc),
             {reply, {ok, Proc, get_query_server_config()}, Server};
         Error ->
             {reply, Error, Server}
         end
     end;
-handle_call({unlink_proc, Pid}, _From, {_, PidProcs, _}=Server) ->    
-    rem_value(PidProcs, Pid),
-    unlink(Pid),
-    {reply, ok, Server};
-handle_call({ret_proc, Proc}, _From, {_, PidProcs, LangProcs}=Server) ->
+handle_call({ret_proc, Proc}, _From, {_, _, LangProcs, InUse}=Server) ->
     % Along with max process limit, here we should check
     % if we're over the limit and discard when we are.
-    add_value(PidProcs, Proc#proc.pid, Proc),
     add_to_list(LangProcs, Proc#proc.lang, Proc),
-    link(Proc#proc.pid),
+    rem_from_list(InUse, Proc#proc.lang, Proc),
     {reply, true, Server}.
 
 handle_cast(_Whatever, Server) ->
     {noreply, Server}.
 
-handle_info({'EXIT', Pid, Status}, {_, PidProcs, LangProcs}=Server) ->
+handle_info({'EXIT', Pid, Status}, {_, PidProcs, LangProcs, InUse}=Server) ->
     case ets:lookup(PidProcs, Pid) of
     [{Pid, Proc}] ->
         case Status of
@@ -315,14 +321,11 @@ handle_info({'EXIT', Pid, Status}, {_, PidProcs, LangProcs}=Server) ->
         end,
         rem_value(PidProcs, Pid),
         catch rem_from_list(LangProcs, Proc#proc.lang, Proc),
+        catch rem_from_list(InUse, Proc#proc.lang, Proc),
         {noreply, Server};
     [] ->
-        case Status of
-        normal ->
-            {noreply, Server};
-        _ ->
-            {stop, Status, Server}
-        end
+        ?LOG_DEBUG("Unknown linked process died: ~p (reason: ~p)", [Pid, Status]),
+        {stop, Status, Server}
     end.
 
 code_change(_OldVsn, State, _Extra) ->
@@ -399,7 +402,6 @@ get_ddoc_process(#doc{} = DDoc, DDocKey) ->
             proc_set_timeout(Proc, list_to_integer(couch_config:get(
                                 "couchdb", "os_process_timeout", "5000"))),
             link(Proc#proc.pid),
-            gen_server:call(couch_query_servers, {unlink_proc, Proc#proc.pid}),
             Proc;
         _ ->
             catch proc_stop(Proc),
@@ -417,7 +419,6 @@ get_os_process(Lang) ->
             proc_set_timeout(Proc, list_to_integer(couch_config:get(
                                 "couchdb", "os_process_timeout", "5000"))),
             link(Proc#proc.pid),
-            gen_server:call(couch_query_servers, {unlink_proc, Proc#proc.pid}),
             Proc;
         _ ->
             catch proc_stop(Proc),