1M process creation in Erlang

processes.erl

module(processes).

-export([max/1]).

%% max(N)
%%  create N processes then destroy them
%%  See how much time this takes

max(N) ->
    Max = erlang:system_info(process_limit),
    io:format("Maximum allowed processes:~p~n", [Max]),
    statistics(wall_clock),
    L = for(1, N, fun() -> spawn(fun() -> wait() end) end),
    {_, Time} = statistics(wall_clock),
    lists:foreach(fun(Pid) -> Pid ! die end, L),    io:format("Elapsed time=~p seconds~n", [Time / 1000.0]).

wait() ->
    receive
        die -> void
    end.

for(N, N, F) -> [F()];
for(I, N, F) -> [F()|for(I+1, N, F)].


%% Results on Macbook Pro Retina 2012
%% CPU: Intel Core i7 2.6 GHz
%% Mem: 16GB 1600 MHz DDR3
%%
%% sh-3.2$ erl +P 2000000
%% Erlang R15B01 (erts-5.9.1) [source] [64-bit] [smp:8:8] [async-threads:0] [hipe] [kernel-poll:false] [dtrace]
%% 
%% Eshell V5.9.1  (abort with ^G)
%% 1> c(processes).
%% {ok,processes}
%% 2> processes:max(50000).
%% Maximum allowed processes:2000000
%% Elapsed time=0.135 seconds
%% ok
%% 3> processes:max(100000).
%% Maximum allowed processes:2000000
%% Elapsed time=0.282 seconds
%% ok
%% 4> processes:max(200000).
%% Maximum allowed processes:2000000
%% Elapsed time=0.535 seconds
%% ok
%% 5> processes:max(500000).
%% Maximum allowed processes:2000000
%% Elapsed time=1.444 seconds
%% ok
%% 6> processes:max(1000000).
%% Maximum allowed processes:2000000
%% Elapsed time=3.123 seconds
%% ok
%% 7>