testing performance of reflection

refl.erl

-module(refl).

-compile(export_all).

normal(Foo) ->
    lists:sort([Foo]).

bad(Mod, Fun, Foo) ->
    Mod:Fun([Foo]).

bench(NumTests) ->
    Seq = lists:seq(1, NumTests),
    {FastTime, _} = timer:tc(fun lists:foreach/2,
        [fun (_) -> normal(foo) end, Seq]),
    timer:sleep(1000),
    {SlowTime, _} = timer:tc(fun lists:foreach/2,
        [fun (_) -> bad(lists, sort, foo) end, Seq]),
    io:format("ResultFast: ~pms~n", [FastTime/1000]),
    io:format("ResultSlow: ~pms~n", [SlowTime/1000]).

-----------------

Eshell V5.9.3  (abort with ^G)
1> refl:bench(1000).
ResultFast: 0.147ms
ResultSlow: 0.239ms
ok
2> refl:bench(1000*1000).
ResultFast: 42.222ms
ResultSlow: 73.34ms
ok
3> refl:bench(100*1000*1000).
ResultFast: 4661.811ms
ResultSlow: 6813.099ms
ok