Collect reductions per process.

[beam_stats.git] / src / beam_stats_delta.erl

diff --git a/src/beam_stats_delta.erl b/src/beam_stats_delta.erl
index 42f2399..45cfdb0 100644 (file)
--- a/src/beam_stats_delta.erl
+++ b/src/beam_stats_delta.erl
@@ -10,10 +10,12 @@
     , of_context_switches/1
     , of_io/1
     , of_reductions/1
+    , of_process_info_reductions/2
     ]).
 
 -record(?MODULE,
     { erlang_statistics :: ets:tid()
+    , erlang_process_info_reductions :: ets:tid()
     }).
 
 -define(T, #?MODULE).
@@ -30,15 +32,19 @@ start() ->
         ],
     ?T
     { erlang_statistics = ets:new(beam_stats_delta_erlang_statistics, Options)
+    , erlang_process_info_reductions =
+        ets:new(beam_stats_delta_erlang_process_info_reductions, Options)
     }.
 
 -spec stop(t()) ->
     {}.
 stop(?T
     { erlang_statistics = TidErlangStatistics
+    , erlang_process_info_reductions = TidErlangProcessInfoReductions
     }
 ) ->
     true = ets:delete(TidErlangStatistics),
+    true = ets:delete(TidErlangProcessInfoReductions),
     {}.
 
 -spec of_context_switches(t()) ->
@@ -75,8 +81,20 @@ of_reductions(?T{erlang_statistics=Table}) ->
     {Current, _} = beam_stats_source:erlang_statistics(Key),
     delta(Table, Key, Current).
 
--spec delta(ets:tid(), atom(), non_neg_integer()) ->
-    non_neg_integer().
+-spec of_process_info_reductions(t(), pid()) ->
+    hope_option:t(non_neg_integer()).
+of_process_info_reductions(?T{erlang_process_info_reductions=Table}, Pid) ->
+    case beam_stats_source:erlang_process_info(Pid, reductions)
+    of  undefined ->
+            none
+    ;   {reductions, Current} ->
+            Delta = delta(Table, Pid, Current),
+            {some, Delta}
+    end.
+
+-spec delta(ets:tid(), Key, non_neg_integer()) ->
+    non_neg_integer()
+    when Key :: atom() | pid().
 delta(Table, Key, CurrentTotal) ->
     PreviousTotalOpt = find(Table, Key),
     PreviousTotal = hope_option:get(PreviousTotalOpt, 0),