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-rw-r--r--src/couchdb/couch_stats_aggregator.erl297
1 files changed, 0 insertions, 297 deletions
diff --git a/src/couchdb/couch_stats_aggregator.erl b/src/couchdb/couch_stats_aggregator.erl
deleted file mode 100644
index 6090355d..00000000
--- a/src/couchdb/couch_stats_aggregator.erl
+++ /dev/null
@@ -1,297 +0,0 @@
-% Licensed under the Apache License, Version 2.0 (the "License"); you may not
-% use this file except in compliance with the License. You may obtain a copy of
-% the License at
-%
-% http://www.apache.org/licenses/LICENSE-2.0
-%
-% Unless required by applicable law or agreed to in writing, software
-% distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-% WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-% License for the specific language governing permissions and limitations under
-% the License.
-
--module(couch_stats_aggregator).
--behaviour(gen_server).
-
--export([start/0, start/1, stop/0]).
--export([all/0, all/1, get/1, get/2, get_json/1, get_json/2, collect_sample/0]).
-
--export([init/1, terminate/2, code_change/3]).
--export([handle_call/3, handle_cast/2, handle_info/2]).
-
--record(aggregate, {
- description = <<"">>,
- seconds = 0,
- count = 0,
- current = null,
- sum = null,
- mean = null,
- variance = null,
- stddev = null,
- min = null,
- max = null,
- samples = []
-}).
-
-
-start() ->
- PrivDir = couch_util:priv_dir(),
- start(filename:join(PrivDir, "stat_descriptions.cfg")).
-
-start(FileName) ->
- gen_server:start_link({local, ?MODULE}, ?MODULE, [FileName], []).
-
-stop() ->
- gen_server:cast(?MODULE, stop).
-
-all() ->
- ?MODULE:all(0).
-all(Time) when is_binary(Time) ->
- ?MODULE:all(list_to_integer(binary_to_list(Time)));
-all(Time) when is_atom(Time) ->
- ?MODULE:all(list_to_integer(atom_to_list(Time)));
-all(Time) when is_integer(Time) ->
- Aggs = ets:match(?MODULE, {{'$1', Time}, '$2'}),
- Stats = lists:map(fun([Key, Agg]) -> {Key, Agg} end, Aggs),
- case Stats of
- [] ->
- {[]};
- _ ->
- Ret = lists:foldl(fun({{Mod, Key}, Agg}, Acc) ->
- CurrKeys = case proplists:lookup(Mod, Acc) of
- none -> [];
- {Mod, {Keys}} -> Keys
- end,
- NewMod = {[{Key, to_json_term(Agg)} | CurrKeys]},
- [{Mod, NewMod} | proplists:delete(Mod, Acc)]
- end, [], Stats),
- {Ret}
- end.
-
-get(Key) ->
- ?MODULE:get(Key, 0).
-get(Key, Time) when is_binary(Time) ->
- ?MODULE:get(Key, list_to_integer(binary_to_list(Time)));
-get(Key, Time) when is_atom(Time) ->
- ?MODULE:get(Key, list_to_integer(atom_to_list(Time)));
-get(Key, Time) when is_integer(Time) ->
- case ets:lookup(?MODULE, {make_key(Key), Time}) of
- [] -> #aggregate{seconds=Time};
- [{_, Agg}] -> Agg
- end.
-
-get_json(Key) ->
- get_json(Key, 0).
-get_json(Key, Time) ->
- to_json_term(?MODULE:get(Key, Time)).
-
-collect_sample() ->
- gen_server:call(?MODULE, collect_sample, infinity).
-
-
-init(StatDescsFileName) ->
- % Create an aggregate entry for each {description, rate} pair.
- ets:new(?MODULE, [named_table, set, protected]),
- SampleStr = couch_config:get("stats", "samples", "[0]"),
- {ok, Samples} = couch_util:parse_term(SampleStr),
- {ok, Descs} = file:consult(StatDescsFileName),
- lists:foreach(fun({Sect, Key, Value}) ->
- lists:foreach(fun(Secs) ->
- Agg = #aggregate{
- description=list_to_binary(Value),
- seconds=Secs
- },
- ets:insert(?MODULE, {{{Sect, Key}, Secs}, Agg})
- end, Samples)
- end, Descs),
-
- Self = self(),
- ok = couch_config:register(
- fun("stats", _) -> exit(Self, config_change) end
- ),
-
- Rate = list_to_integer(couch_config:get("stats", "rate", "1000")),
- % TODO: Add timer_start to kernel start options.
- {ok, TRef} = timer:apply_after(Rate, ?MODULE, collect_sample, []),
- {ok, {TRef, Rate}}.
-
-terminate(_Reason, {TRef, _Rate}) ->
- timer:cancel(TRef),
- ok.
-
-handle_call(collect_sample, _, {OldTRef, SampleInterval}) ->
- timer:cancel(OldTRef),
- {ok, TRef} = timer:apply_after(SampleInterval, ?MODULE, collect_sample, []),
- % Gather new stats values to add.
- Incs = lists:map(fun({Key, Value}) ->
- {Key, {incremental, Value}}
- end, couch_stats_collector:all(incremental)),
- Abs = lists:map(fun({Key, Values}) ->
- couch_stats_collector:clear(Key),
- Values2 = case Values of
- X when is_list(X) -> X;
- Else -> [Else]
- end,
- {_, Mean} = lists:foldl(fun(Val, {Count, Curr}) ->
- {Count+1, Curr + (Val - Curr) / (Count+1)}
- end, {0, 0}, Values2),
- {Key, {absolute, Mean}}
- end, couch_stats_collector:all(absolute)),
-
- Values = Incs ++ Abs,
- Now = erlang:now(),
- lists:foreach(fun({{Key, Rate}, Agg}) ->
- NewAgg = case proplists:lookup(Key, Values) of
- none ->
- rem_values(Now, Agg);
- {Key, {Type, Value}} ->
- NewValue = new_value(Type, Value, Agg#aggregate.current),
- Agg2 = add_value(Now, NewValue, Agg),
- rem_values(Now, Agg2)
- end,
- ets:insert(?MODULE, {{Key, Rate}, NewAgg})
- end, ets:tab2list(?MODULE)),
- {reply, ok, {TRef, SampleInterval}}.
-
-handle_cast(stop, State) ->
- {stop, normal, State}.
-
-handle_info(_Info, State) ->
- {noreply, State}.
-
-code_change(_OldVersion, State, _Extra) ->
- {ok, State}.
-
-
-new_value(incremental, Value, null) ->
- Value;
-new_value(incremental, Value, Current) ->
- Value - Current;
-new_value(absolute, Value, _Current) ->
- Value.
-
-add_value(Time, Value, #aggregate{count=Count, seconds=Secs}=Agg) when Count < 1 ->
- Samples = case Secs of
- 0 -> [];
- _ -> [{Time, Value}]
- end,
- Agg#aggregate{
- count=1,
- current=Value,
- sum=Value,
- mean=Value,
- variance=0.0,
- stddev=null,
- min=Value,
- max=Value,
- samples=Samples
- };
-add_value(Time, Value, Agg) ->
- #aggregate{
- count=Count,
- current=Current,
- sum=Sum,
- mean=Mean,
- variance=Variance,
- samples=Samples
- } = Agg,
-
- NewCount = Count + 1,
- NewMean = Mean + (Value - Mean) / NewCount,
- NewVariance = Variance + (Value - Mean) * (Value - NewMean),
- StdDev = case NewCount > 1 of
- false -> null;
- _ -> math:sqrt(NewVariance / (NewCount - 1))
- end,
- Agg2 = Agg#aggregate{
- count=NewCount,
- current=Current + Value,
- sum=Sum + Value,
- mean=NewMean,
- variance=NewVariance,
- stddev=StdDev,
- min=lists:min([Agg#aggregate.min, Value]),
- max=lists:max([Agg#aggregate.max, Value])
- },
- case Agg2#aggregate.seconds of
- 0 -> Agg2;
- _ -> Agg2#aggregate{samples=[{Time, Value} | Samples]}
- end.
-
-rem_values(Time, Agg) ->
- Seconds = Agg#aggregate.seconds,
- Samples = Agg#aggregate.samples,
- Pred = fun({When, _Value}) ->
- timer:now_diff(Time, When) =< (Seconds * 1000000)
- end,
- {Keep, Remove} = lists:splitwith(Pred, Samples),
- Agg2 = lists:foldl(fun({_, Value}, Acc) ->
- rem_value(Value, Acc)
- end, Agg, Remove),
- Agg2#aggregate{samples=Keep}.
-
-rem_value(_Value, #aggregate{count=Count, seconds=Secs}) when Count =< 1 ->
- #aggregate{seconds=Secs};
-rem_value(Value, Agg) ->
- #aggregate{
- count=Count,
- sum=Sum,
- mean=Mean,
- variance=Variance
- } = Agg,
-
- OldMean = (Mean * Count - Value) / (Count - 1),
- OldVariance = Variance - (Value - OldMean) * (Value - Mean),
- OldCount = Count - 1,
- StdDev = case OldCount > 1 of
- false -> null;
- _ -> math:sqrt(clamp_value(OldVariance / (OldCount - 1)))
- end,
- Agg#aggregate{
- count=OldCount,
- sum=Sum-Value,
- mean=clamp_value(OldMean),
- variance=clamp_value(OldVariance),
- stddev=StdDev
- }.
-
-to_json_term(Agg) ->
- {Min, Max} = case Agg#aggregate.seconds > 0 of
- false ->
- {Agg#aggregate.min, Agg#aggregate.max};
- _ ->
- case length(Agg#aggregate.samples) > 0 of
- true ->
- Extract = fun({_Time, Value}) -> Value end,
- Samples = lists:map(Extract, Agg#aggregate.samples),
- {lists:min(Samples), lists:max(Samples)};
- _ ->
- {null, null}
- end
- end,
- {[
- {description, Agg#aggregate.description},
- {current, round_value(Agg#aggregate.sum)},
- {sum, round_value(Agg#aggregate.sum)},
- {mean, round_value(Agg#aggregate.mean)},
- {stddev, round_value(Agg#aggregate.stddev)},
- {min, Min},
- {max, Max}
- ]}.
-
-make_key({Mod, Val}) when is_integer(Val) ->
- {Mod, list_to_atom(integer_to_list(Val))};
-make_key(Key) ->
- Key.
-
-round_value(Val) when not is_number(Val) ->
- Val;
-round_value(Val) when Val == 0 ->
- Val;
-round_value(Val) ->
- erlang:round(Val * 1000.0) / 1000.0.
-
-clamp_value(Val) when Val > 0.00000000000001 ->
- Val;
-clamp_value(_) ->
- 0.0.
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-18 12:54:53 +0000