From: nobu.nokada@...
Date: 2004-07-15T20:37:22+09:00
Subject: Re: my ruby code won't go as fast as my perl code

Hi,

At Thu, 15 Jul 2004 15:07:18 +0900,
Dave Burt wrote in [ruby-talk:106480]:
> I realise I'm doing this a perlish way, but my question is, is it possible
> to do this operation in Ruby in a time more comparable to what the Perl
> version's getting? (That's about 4 seconds; my Ruby code runs in about 17
> seconds over the same data set, which is far smaller than the production
> data set.)

Which version of ruby do you use?

> Dir.open(dir).each do |file|
>  next if file[0] == ?.  # skip dotfiles
>  reading = false
>  File.open(dir + '/' + file).each_line do |line|
>   reading ||= (date_regex =~ line &&
> (($3>='87'?'19':'20')+$3+mm[$2]+$1+$4+$5+$6 >= start_date))
>   a << line if reading
>  end
> end

You open files but never close, this may cause too frequent GC.

  IO.foreach(dir + '/' + file) do |line|
    if reading
      a << line
    else
      reading = (date_regex =~ line &&
        (($3>='87'?'19':'20')+$3+mm[$2]+$1+$4+$5+$6 >= start_date))
    end
  end

-- 
Nobu Nakada