Add stats in fabric for partition and normal views (#1963)

Add metrics for partition queries

This adds httpd metrics to monitor the number of request for partition
queries. It also adds metrics to record the number of timeouts for
partition and global query requests

4 files changed, 104 insertions, 5 deletions

diff --git a/src/chttpd/src/chttpd.erl b/src/chttpd/src/chttpd.erl
index 631eb77c9..ac371a2e5 100644
--- a/src/chttpd/src/chttpd.erl
+++ b/src/chttpd/src/chttpd.erl
@@ -810,7 +810,8 @@ send_delayed_error(#delayed_resp{req=Req,resp=nil}=DelayedResp, Reason) ->
     {Code, ErrorStr, ReasonStr} = error_info(Reason),
     {ok, Resp} = send_error(Req, Code, ErrorStr, ReasonStr),
     {ok, DelayedResp#delayed_resp{resp=Resp}};
-send_delayed_error(#delayed_resp{resp=Resp}, Reason) ->
+send_delayed_error(#delayed_resp{resp=Resp, req=Req}, Reason) ->
+    update_timeout_stats(Reason, Req),
     log_error_with_stack_trace(Reason),
     throw({http_abort, Resp, Reason}).
 
@@ -1025,12 +1026,15 @@ error_headers(_, Code, _, _) ->
 send_error(_Req, {already_sent, Resp, _Error}) ->
     {ok, Resp};
 
-send_error(Req, Error) ->
+send_error(#httpd{} = Req, Error) ->
+    update_timeout_stats(Error, Req),
+
     {Code, ErrorStr, ReasonStr} = error_info(Error),
     {Code1, Headers} = error_headers(Req, Code, ErrorStr, ReasonStr),
     send_error(Req, Code1, Headers, ErrorStr, ReasonStr, json_stack(Error)).
 
-send_error(Req, Code, ErrorStr, ReasonStr) ->
+send_error(#httpd{} = Req, Code, ErrorStr, ReasonStr) ->
+    update_timeout_stats(ErrorStr, Req),
     send_error(Req, Code, [], ErrorStr, ReasonStr, []).
 
 send_error(Req, Code, Headers, ErrorStr, ReasonStr, []) ->
@@ -1045,6 +1049,33 @@ send_error(Req, Code, Headers, ErrorStr, ReasonStr, Stack) ->
         case Stack of [] -> []; _ -> [{<<"ref">>, stack_hash(Stack)}] end
     ]}).
 
+update_timeout_stats(<<"timeout">>, #httpd{requested_path_parts = PathParts}) ->
+    update_timeout_stats(PathParts);
+update_timeout_stats(timeout, #httpd{requested_path_parts = PathParts}) ->
+    update_timeout_stats(PathParts);
+update_timeout_stats(_, _) ->
+    ok.
+
+update_timeout_stats([_, <<"_partition">>, _, <<"_design">>, _,
+        <<"_view">> | _]) ->
+    couch_stats:increment_counter([couchdb, httpd, partition_view_timeouts]);
+update_timeout_stats([_, <<"_partition">>, _, <<"_find">>| _]) ->
+    couch_stats:increment_counter([couchdb, httpd, partition_find_timeouts]);
+update_timeout_stats([_, <<"_partition">>, _, <<"_explain">>| _]) ->
+    couch_stats:increment_counter([couchdb, httpd, partition_explain_timeouts]);
+update_timeout_stats([_, <<"_partition">>, _, <<"_all_docs">> | _]) ->
+    couch_stats:increment_counter([couchdb, httpd, partition_all_docs_timeouts]);
+update_timeout_stats([_, <<"_design">>, _, <<"_view">> | _]) ->
+    couch_stats:increment_counter([couchdb, httpd, view_timeouts]);
+update_timeout_stats([_, <<"_find">>| _]) ->
+    couch_stats:increment_counter([couchdb, httpd, find_timeouts]);
+update_timeout_stats([_, <<"_explain">>| _]) ->
+    couch_stats:increment_counter([couchdb, httpd, explain_timeouts]);
+update_timeout_stats([_, <<"_all_docs">> | _]) ->
+    couch_stats:increment_counter([couchdb, httpd, all_docs_timeouts]);
+update_timeout_stats(_) ->
+    ok.
+
 % give the option for list functions to output html or other raw errors
 send_chunked_error(Resp, {_Error, {[{<<"body">>, Reason}]}}) ->
     send_chunk(Resp, Reason),
diff --git a/src/chttpd/src/chttpd_db.erl b/src/chttpd/src/chttpd_db.erl
index 5a0911559..c6404b04d 100644
--- a/src/chttpd/src/chttpd_db.erl
+++ b/src/chttpd/src/chttpd_db.erl
@@ -298,6 +298,7 @@ handle_partition_req(#httpd{path_parts=[DbName, _, PartId | Rest]}=Req, Db) ->
                 path_parts = [DbName | Rest],
                 qs = NewQS
             },
+            update_partition_stats(Rest),
             case Rest of
                 [OP | _] when OP == <<"_all_docs">> orelse ?IS_MANGO(OP) ->
                     case chttpd_handlers:db_handler(OP, fun db_req/2) of
@@ -318,6 +319,20 @@ handle_partition_req(#httpd{path_parts=[DbName, _, PartId | Rest]}=Req, Db) ->
 handle_partition_req(Req, _Db) ->
     chttpd:send_error(Req, not_found).
 
+update_partition_stats(PathParts) ->
+    case PathParts of
+            [<<"_design">> | _] ->
+                couch_stats:increment_counter([couchdb, httpd, partition_view_requests]);
+            [<<"_all_docs">> | _] ->
+                couch_stats:increment_counter([couchdb, httpd, partition_all_docs_requests]);
+            [<<"_find">> | _] ->
+                couch_stats:increment_counter([couchdb, httpd, partition_find_requests]);
+            [<<"_explain">> | _] ->
+                couch_stats:increment_counter([couchdb, httpd, partition_explain_requests]);
+            _ ->
+                ok % ignore path that do not match
+        end.
+
 
 handle_design_req(#httpd{
         path_parts=[_DbName, _Design, Name, <<"_",_/binary>> = Action | _Rest]
diff --git a/src/couch/priv/stats_descriptions.cfg b/src/couch/priv/stats_descriptions.cfg
index e5ac9d722..0e2271350 100644
--- a/src/couch/priv/stats_descriptions.cfg
+++ b/src/couch/priv/stats_descriptions.cfg
@@ -78,6 +78,54 @@
     {type, counter},
     {desc, <<"number of HTTP requests">>}
 ]}.
+{[couchdb, httpd, view_timeouts], [
+    {type, counter},
+    {desc, <<"number of HTTP view timeouts">>}
+]}.
+{[couchdb, httpd, find_timeouts], [
+    {type, counter},
+    {desc, <<"number of HTTP find timeouts">>}
+]}.
+{[couchdb, httpd, explain_timeouts], [
+    {type, counter},
+    {desc, <<"number of HTTP _explain timeouts">>}
+]}.
+{[couchdb, httpd, all_docs_timeouts], [
+    {type, counter},
+    {desc, <<"number of HTTP all_docs timeouts">>}
+]}.
+{[couchdb, httpd, partition_view_requests], [
+    {type, counter},
+    {desc, <<"number of partition HTTP view requests">>}
+]}.
+{[couchdb, httpd, partition_find_requests], [
+    {type, counter},
+    {desc, <<"number of partition HTTP _find requests">>}
+]}.
+{[couchdb, httpd, partition_explain_requests], [
+    {type, counter},
+    {desc, <<"number of partition HTTP _explain requests">>}
+]}.
+{[couchdb, httpd, partition_all_docs_requests], [
+    {type, counter},
+    {desc, <<"number of partition HTTP _all_docs requests">>}
+]}.
+{[couchdb, httpd, partition_view_timeouts], [
+    {type, counter},
+    {desc, <<"number of partition HTTP view timeouts">>}
+]}.
+{[couchdb, httpd, partition_find_timeouts], [
+    {type, counter},
+    {desc, <<"number of partition HTTP find timeouts">>}
+]}.
+{[couchdb, httpd, partition_explain_timeouts], [
+    {type, counter},
+    {desc, <<"number of partition HTTP _explain timeouts">>}
+]}.
+{[couchdb, httpd, partition_all_docs_timeouts], [
+    {type, counter},
+    {desc, <<"number of partition HTTP all_docs timeouts">>}
+]}.
 {[couchdb, httpd, temporary_view_reads], [
     {type, counter},
     {desc, <<"number of temporary view reads">>}
diff --git a/src/mango/src/mango_httpd.erl b/src/mango/src/mango_httpd.erl
index d73ec6cb5..379d2e127 100644
--- a/src/mango/src/mango_httpd.erl
+++ b/src/mango/src/mango_httpd.erl
@@ -186,8 +186,13 @@ handle_find_req(#httpd{method='POST'}=Req, Db) ->
     {ok, Opts0} = mango_opts:validate_find(Body),
     {value, {selector, Sel}, Opts} = lists:keytake(selector, 1, Opts0),
     {ok, Resp0} = start_find_resp(Req),
-    {ok, AccOut} = run_find(Resp0, Db, Sel, Opts),
-    end_find_resp(AccOut);
+    case run_find(Resp0, Db, Sel, Opts) of
+        {ok, AccOut} ->
+            end_find_resp(AccOut);
+        {error, Error} ->
+            chttpd:send_error(Req, Error)
+    end;
+
 
 handle_find_req(Req, _Db) ->
     chttpd:send_method_not_allowed(Req, "POST").