From: Michael Fellinger <m.fellinger@...>
Date: 2006-10-26T19:07:26+09:00
Subject: Re: Simple method overhead

On Thursday 26 October 2006 18:31, vshepelev@imho.com.ua wrote:
> Hi all.
>
> I have the method like:
> class MyCoolClass
>   def initialize
>     @var = []
>   end
>
>   #some other methods push values to @var
>
>   #here is method of interest:
>   def [](idx); @var[idx] end
> end
>
> I have those, a bit confusing, profiling results:
>
> Total   Self    Children	Calls    Name
> 0.09    0.05    0.04        66565    MyCoolClass#[]
> 0.04    0.04    0.00        66565    Array#[]
>
> The strange thing is: method MyCoolClass#[] spends so much time inside
> itself, though ALL it do - only call Array#[]. Is this normal? Maybe,
> because of so huge calls count, but I can't understand this :(
>
> Thanks.
>
> V.

methods have quite some overhead, so to say :)
and this benchmark almost covers your values... so i'd say, yeah - it's simply 
the overhead

# the code
require 'benchmark'

def one;       end
def two;   one end
def three; two end

iterate = 66_565

Benchmark.bmbm(20) do |x|
  x.report("one  :")  { iterate.times{  one  } }
  x.report("two  :")  { iterate.times{  two  } }
  x.report("three:")  { iterate.times{ three } }
end

=begin result
                          user     system      total        real
one:                  0.080000   0.020000   0.100000 (  0.090971)
two:                  0.080000   0.060000   0.140000 (  0.134608)
three:                0.190000   0.040000   0.230000 (  0.325138)
=end