Add dedicated monitor processes option
diff --git a/src/couch_stats/src/couch_stats_resource_tracker.erl b/src/couch_stats/src/couch_stats_resource_tracker.erl
index bdedd81..2774f7f 100644
--- a/src/couch_stats/src/couch_stats_resource_tracker.erl
+++ b/src/couch_stats/src/couch_stats_resource_tracker.erl
@@ -48,7 +48,8 @@
set_context_dbname/1,
set_context_handler_fun/1,
set_context_username/1,
- track/1,
+ track/1, tracker/1,
+ stop_tracker/0, stop_tracker/1, stop_tracker/2,
should_track/1
]).
@@ -140,6 +141,7 @@
-define(DELTA_TA, csrt_delta_ta).
-define(DELTA_TZ, csrt_delta_tz). %% T Zed instead of T0
-define(PID_REF, csrt_pid_ref). %% track local ID
+-define(TRACKER_PID, csrt_tracker). %% tracker pid
-record(st, {
@@ -675,6 +677,7 @@
destroy_context(undefined) ->
ok;
destroy_context({_, _} = PidRef) ->
+ stop_tracker(PidRef),
close_pid_ref(PidRef),
gen_server:cast(?MODULE, {destroy, PidRef}),
ok.
@@ -800,11 +803,80 @@
end
end.
-track(#rctx{pid_ref=PidRef}) ->
+track(#rctx{}=Rctx) ->
+ case conf_get("spawn_monitor", "true") of
+ "true" ->
+ track(Rctx, spawn_monitor);
+ _ ->
+ track(Rctx, gen_server)
+ end.
+
+track(#rctx{pid_ref=PidRef}, spawn_monitor) ->
+ case get_tracker() of
+ undefined ->
+ Pid = spawn(?MODULE, tracker, [PidRef]),
+ put_tracker(Pid);
+ Pid when is_pid(Pid) ->
+ Pid
+ end;
+track(#rctx{pid_ref=PidRef}, gen_server) ->
%% TODO: should this block or not? If no, what cleans up zombies?
%% gen_server:call(?MODULE, {track, PR}).
gen_server:cast(?MODULE, {track, PidRef}).
+get_tracker() ->
+ get(?TRACKER_PID).
+
+put_tracker(Pid) when is_pid(Pid) ->
+ put(?TRACKER_PID, Pid).
+
+tracker({Pid, _Ref}=PidRef) ->
+ MonRef = erlang:monitor(process, Pid),
+ should_scan() andalso catch ets:update_element(?MODULE, PidRef, [{#rctx.mon_ref, MonRef}]),
+ receive
+ stop ->
+ %% TODO: do we need cleanup here?
+ %%cleanup_tracker(PidRef, <<"shutdown:stopped">>),
+ demonitor(MonRef),
+ ok;
+ {'DOWN', MonRef, _Type, _0DPid, Reason0} ->
+ Reason = case Reason0 of
+ {shutdown, Shutdown0} ->
+ Shutdown = atom_to_binary(Shutdown0),
+ <<"shutdown: ", Shutdown/binary>>;
+ Reason0 ->
+ Reason0
+ end,
+ cleanup_tracker(PidRef, Reason)
+ end.
+
+cleanup_tracker(PidRef, Reason) ->
+ case is_logging_enabled() andalso get_resource(PidRef) of
+ #rctx{} = Rctx ->
+ should_log(Rctx) andalso log_process_lifetime_report(PidRef, Rctx);
+ _ ->
+ ok
+ end,
+ %% update stats
+ should_scan() andalso catch ets:update_element(?MODULE, PidRef,
+ [{#rctx.state, {down, Reason}}, {#rctx.updated_at, tnow()}]),
+ catch evict(PidRef).
+
+
+stop_tracker() ->
+ stop_tracker(get_tracker(), get_pid_ref()).
+
+stop_tracker({_Pid, _Ref}=PidRef) ->
+ stop_tracker(get_tracker(), PidRef);
+stop_tracker(Pid) when is_pid(Pid) ->
+ stop_tracker(Pid, get_pid_ref()).
+
+stop_tracker(undefined, _) ->
+ ok;
+stop_tracker(Pid, PidRef) ->
+ should_scan() andalso catch ets:update_element(?MODULE, PidRef, [{#rctx.mon_ref, undefined}]),
+ Pid ! stop.
+
make_delta() ->
TA = case get(?DELTA_TA) of
@@ -916,9 +988,6 @@
catch get_resource_int(PidRef).
-get_resource_int() ->
- get_resource_int(get_pid_ref()).
-
get_resource_int(undefined) ->
undefined;
get_resource_int(PidRef) ->
@@ -1100,12 +1169,13 @@
case is_enabled() andalso is_logging_enabled() of
true ->
Rctx = get_resource_int(PidRef),
- should_log(Rctx) andalso
- couch_log:report("csrt-pid-usage-lifetime", to_flat_json(Rctx));
+ should_log(Rctx) andalso log_process_lifetime_report(PidRef, Rctx);
false ->
ok
end.
+log_process_lifetime_report(_PidRef, Rctx) ->
+ couch_log:report("csrt-pid-usage-lifetime", to_flat_json(Rctx)).
is_logging_enabled() ->
logging_enabled() =/= false.
@@ -1121,10 +1191,14 @@
end.
+should_log(undefined) ->
+ false;
should_log(#rctx{}=Rctx) ->
should_log(Rctx, logging_enabled()).
+should_log(undefined, _) ->
+ false;
should_log(#rctx{}, true) ->
true;
should_log(#rctx{}, false) ->
