From: Sean Russell <ser@...>
Date: 2001-11-10T03:48:21+09:00
Subject: [ruby-talk:24790] Re: Why is ruby slow (compared to perl)

Robert Feldt wrote:

> I think we basically agree. BTW, I like rebellion so keep up the good
> spirit! ;-)

Heh.  No! ;-)

> Funny enough my impression of XP is more like "here are some cool
> rule-breakers that kind-of worked for us". I probably misread them and
> jumped to conclusions. I tend to do that... ;-)

Oh, I don't know.  That is probably how it started, and probably how a lot 
of people think about it.  XP replaced a lot of old rules with some new 
ones that I think work better, if you don't take them *too* seriously.

> Yes. However, often I find the most dramatic speed improvements come from
> checking if all the things done are necessary, if the algorithms used have
> "good" (algorithmic) complexity and wallclock timing properties, which
> data structures have been chosen and how this affects the algorithms. For
> Ruby its also important to use built-in methods. Further along down the
> list is to create few objects. "Manually" inlining stuff is not
> high on this list. However, when its needed I think its better done after
> the performance problem is real and not as a "premature
> optimization". But, then again, who can make absolute statements about an
> ever changing world. Lets just expand our bag of
> tools/patterns/methods/ideas...

Yeah, I think we're on the same track.  As I mentioned, though, inlining a 
single "yield" in an oft-called method can make a huge difference in 
execution speed.

> Anyway, I think we basically agree. And I'm a recent convert myself... ;-)

You know, it seems impossible to find an employer who is willing to buy 
into all of the really cool stuff, like XP and Ruby.

--- SER