Merge pull request #162 from gomoripeti/hist

Address hdr_histogram issues

.travis.yml

@@ -7,6 +7,8 @@ matrix:
     include:
         - otp_release: 20.0
         - otp_release: 19.3
+        - otp_release: 19.3
+          env: XPROF_ERL_HIST=true
         - otp_release: 18.3
           env: COWBOY_VERSION=1.1.2
         - otp_release: 17.5

README.md

@@ -199,7 +199,7 @@ Registry.dispatch(MyApp.Registry, "topic1", _) -> nil; (MyApp.Registry, "topic2"
 
 ## Erlang records
 
-Elrang record syntax is supported in the queries and works similar to the Erlang
+Erlang record syntax is supported in the queries and works similar to the Erlang
 shell. XProf keeps a single global list of loaded record definitions. Record
 definitions can be loaded at startup time from modules listed in app env
 `load_records` or at runtime calling `xprof_core:rr(Module)` (see documentation
@@ -208,6 +208,19 @@ debug_info of the beam files belonging to the loaded modules. As the list is
 global there can be only one record with the same name loaded at a time and
 records loaded later might override previously loaded ones.
 
+## Compile-time configuration
+
+`XPROF_ERL_HIST` - By default XProf uses the `hdr_histogram_erl` NIF
+library. If you have compilation problems you can choose to use a
+native Erlang histogram implementation by defining the OS env var
+`XPROF_ERL_HIST` when compiling `xprof_core`.
+
+`COWBOY_VERSION` - By default XProf uses Cowboy version 2.x. This
+version is only supported from Erlang/OTP 19 and is not backwards
+compatible with older Cowboy versions. If for some reason you would
+like to use Cowboy version 1.x you can define the OS env var
+`COWBOY_VERSION=1` when compiling `xprof_gui`.
+
 ## Contributing
 
 All improvements, fixes and ideas are very welcomed!

apps/xprof_core/rebar.config

@@ -1,8 +1,11 @@
 {deps,
- [{customized_hdr_histogram, "0.3.2"},
+ [{hdr_histogram, "0.3.2"},
   {lager, "3.2.4"}
  ]}.
 
 {erl_opts, [debug_info,
             {parse_transform, lager_transform},
-            {platform_define, "^((1[8|9])|2)", rand_module}]}.
+            {platform_define, "^(R|17|18)", before_OTP_19},
+            {platform_define, "^((1[8|9])|2)", rand_module},
+            {platform_define, "^[^R1]", ceil_floor}
+           ]}.

apps/xprof_core/rebar.config.script

@@ -0,0 +1,12 @@
+case os:getenv("XPROF_ERL_HIST") of
+    false ->
+        CONFIG;
+    _ ->
+        ErlOpts = proplists:get_value(erl_opts, CONFIG, []),
+        NewErlOpts = {erl_opts, [{d, 'XPROF_ERL_HIST'}|ErlOpts]},
+        Config2 = lists:keystore(erl_opts, 1, CONFIG, NewErlOpts),
+
+        Deps = proplists:get_value(deps, CONFIG, []),
+        NewDeps = {deps, lists:keydelete(hdr_histogram, 1, Deps)},
+        lists:keystore(deps, 1, Config2, NewDeps)
+end.

apps/xprof_core/src/xprof_core.app.src

@@ -8,7 +8,7 @@
    ,stdlib
    ,compiler
    ,lager
-   ,customized_hdr_histogram
+   ,hdr_histogram
    ]}
  ,{env,[]}
  ,{modules, []}

apps/xprof_core/src/xprof_core_cmd_funlatency.erl

@@ -86,7 +86,7 @@ init(Options, _MFASpec) ->
                   undefined -> undefined;
                   _ -> 0
               end,
-    {ok, HDR} = hdr_histogram:open(MaxDuration, 3),
+    {ok, HDR} = xprof_core_hist:hdr_new(MaxDuration, 3),
     {ok, #state{hdr_ref = HDR,
                 max_duration = MaxDuration,
                 ignore_recursion = IgnoreRecursion,
@@ -116,9 +116,9 @@ handle_event({trace_ts, Pid, Tag, MFA, RetOrExc, EndTime},
                             lager:error("Call ~p took ~p ms that is larger than the maximum "
                                         "that can be stored (~p ms)",
                                         [MFA, CallTime/1000, MaxDuration div 1000]),
-                            ok = hdr_histogram:record(Ref, MaxDuration);
+                            ok = xprof_core_hist:hdr_record(Ref, MaxDuration);
                        true ->
-                            ok = hdr_histogram:record(Ref, CallTime)
+                            ok = xprof_core_hist:hdr_record(Ref, CallTime)
                     end,
 
                     maybe_capture({Pid, CallTime, Args, {Tag, NewRet}},
@@ -128,7 +128,7 @@ handle_event({trace_ts, Pid, Tag, MFA, RetOrExc, EndTime},
 
 take_snapshot(State = #state{hdr_ref = Ref, nomatch_count = NoMatch}) ->
     Snapshot = get_current_hist_stats(Ref, NoMatch),
-    hdr_histogram:reset(Ref),
+    xprof_core_hist:hdr_reset(Ref),
     maybe_reset_nomatch_count(Snapshot, State, NoMatch).
 
 maybe_reset_nomatch_count(Snapshot, _State, _NoMatch = undefined) ->
@@ -211,30 +211,16 @@ maybe_capture({_Pid, CallTime, Args, _Res} = Item, Threshold, _State) ->
     end.
 
 get_current_hist_stats(HistRef, NoMatch) ->
-    Count = hdr_histogram:get_total_count(HistRef),
-    TotalCountAndRate =
-        case NoMatch of
-            undefined ->
-                [];
-            _ ->
-                TotalCount = Count + NoMatch,
-                [{total_count, TotalCount},
-                 {match_rate, percent(Count, TotalCount)}]
-        end,
-    [{min,         hdr_histogram:min(HistRef)},
-     {mean,        hdr_histogram:mean(HistRef)},
-     %%{median,      hdr_histogram:median(HistRef)},
-     {max,         hdr_histogram:max(HistRef)},
-     %%{stddev,      hdr_histogram:stddev(HistRef)},
-     %%{p25,         hdr_histogram:percentile(HistRef,25.0)},
-     {p50,         hdr_histogram:percentile(HistRef,50.0)},
-     {p75,         hdr_histogram:percentile(HistRef,75.0)},
-     {p90,         hdr_histogram:percentile(HistRef,90.0)},
-     {p99,         hdr_histogram:percentile(HistRef,99.0)},
-     %%{p9999999,    hdr_histogram:percentile(HistRef,99.9999)},
-     %%{memsize,     hdr_histogram:get_memory_size(HistRef)},
-     {count,       Count}
-     |TotalCountAndRate].
+    [{count, Count}|_] = Stats = xprof_core_hist:hdr_stats(HistRef),
+    case NoMatch of
+        undefined ->
+            Stats;
+        _ ->
+            TotalCount = Count + NoMatch,
+            [{total_count, TotalCount},
+             {match_rate, percent(Count, TotalCount)}
+             |Stats]
+    end.
 
 percent(_, 0) ->
     0;