the beginning of bringing benchee back

README.md

@@ -176,15 +176,16 @@ it is included the override is necessary.
 Running benchmarks is done with [benchee](https://github.com/bencheeorg/benchee). Benchmark functions are in modules under `samples/`. To run them open a rebar3 shell in the `bench` profile:
 
 ``` shell
-$ rebar3 as bench compile
+$ rebar3 as bench shell
 
 > otel_benchmarks:run().
 ```
 
-If an Elixir script is wanted for the benchmarks they could be run like:
+If an Elixir script is wanted for the benchmarks they could be run like (after
+running `rebar3 as bench compile`):
 
 ``` shell
-$ ERL_LIBS=_build/bench/lib/ mix run --no-mix-exs samples/run.exs
+$ ERL_AFLAGS="-pa ./_build/bench/extras/samples/" ERL_LIBS=_build/bench/lib/ mix run --no-mix-exs samples/run.exs
 ```
 
 ## W3C Trace Context Interop Tests

config/bench.config

@@ -0,0 +1,7 @@
+[
+ {opentelemetry,
+  [{processors, [{otel_batch_processor,
+                  #{exporter => none}
+                 }]
+   }]}
+].

config/sys.config

@@ -1,7 +1,3 @@
 [
- {opentelemetry,
-  [{processors, [{otel_batch_processor,
-                  #{exporter => {otel_exporter_stdout, []}}
-                 }]
-   }]}
+ {opentelemetry, []}
 ].

rebar.config

@@ -29,9 +29,13 @@
              {extra_src_dirs, ["interop"]}]},
 
   {bench, [{deps, [benchee]},
-           {extra_src_dirs, ["bench"]},
+           {extra_src_dirs, ["samples"]},
            {plugins, [rebar_mix]},
-           {provider_hooks, [{pre, [{compile, {mix, find_elixir_libs}}]}]}]}]}.
+           {provider_hooks, []},
+
+           {shell, [{apps, [opentelemetry,
+                            opentelemetry_experimental]},
+                    {config, "config/bench.config"}]}]}]}.
 
 {xref_checks, [undefined_function_calls, undefined_functions, locals_not_used,
                deprecated_function_calls, deprecated_functions]}.

samples/otel_benchmarks.erl

@@ -0,0 +1,22 @@
+-module(otel_benchmarks).
+
+-export([run/0]).
+
+-include_lib("opentelemetry_api/include/otel_tracer.hrl").
+
+%% doesn't currently show anything useful
+run() ->
+    PDictCtxFun = fun() ->
+                          ?start_span(a_span),
+                          ?end_span()
+                  end,
+
+    CtxFun = fun() ->
+                     Tracer = opentelemetry:get_application_tracer(?MODULE),
+                     SpanCtx = otel_tracer:start_span(Tracer, a_span, #{}),
+                     otel_span:end_span(SpanCtx)
+             end,
+
+    benchee:run(#{<<"pdict_ctx">> => PDictCtxFun,
+                  <<"ctx">> => CtxFun}),
+    ok.

samples/run.exs

@@ -1,4 +1,4 @@
 # this file makes it possible to run the benchmarks in CI
 # with `mix run`
 
-:ot_benchmarks.run()
+:otel_benchmarks.run()