From: Robert Klemme <bob.news@...>
Date: 2003-04-16T22:12:26+09:00
Subject: Re: profile.rb overhead


"Tim Bates" <tim@bates.id.au> schrieb im Newsbeitrag
news:200304161320.52562.tim@bates.id.au...
> I have a script.
>
> tim@zaphod:~/ruby$ ruby -v
> ruby 1.6.7 (2002-03-19) [i386-linux]
> tim@zaphod:~/ruby$ time ruby test1.rb
>
> real    0m22.490s
> user    0m20.010s
> sys     0m0.340s
>
> So far, so good.
> But when I try to profile this script, it runs for ages:
>
> tim@zaphod:~/ruby$ time ruby -r profile test1.rb
>   %   cumulative   self              self     total
>  time   seconds   seconds    calls  ms/call  ms/call  name
>  39.60   395.46    395.46    77090     5.13    17.16  Array#each
> ..
>
> real    18m37.780s
> user    16m38.740s
> sys     0m6.580s
>
> Now I realise that the profiler must have some overhead, but this is
> ridiculous - it's taking 50 times longer! I've run similar scripts
through
> the profiler before, and I've never seen an increase like this. Any
ideas?

The profiler overhead increases with increased number of invocations of
small methods.  Array#each seems to be called quite often, so this might
be the reason for the overhead.

Regards

    robert