From: Stefan Matthias Aust <sma@3plus4.de>
Date: 2001-05-06T03:41:23+09:00
Subject: [ruby-talk:14717] Re: Why's Ruby so slow in this case?

"David S." <dgjs@acm.org> wrote:

>It seems to me that your code is spending most of its time in the
>range loops.

Unfortunately, this doesn't have any measurable effect.

But I've to do an awkward update on my earlier posting:  I suffered
from a "Heisenbug", I didn't notice that the profiler was responsible
for the slowness it measured.  It at least adds a factor of 10..100 to
the total execution time!

So I used a different method to time my application.  To get a better
impression of the real execution time, I used first

 time ruby -w -e '100000.times{}'

to measure the constant overhead for initializing the interpreter and
looping through the test loop and then run

 time ruby -w -e '$m=35;def o(x,y)x>=0 && x<$m && y>=0 \
   && y<$m end; 100000.times{o(4,4)}'

and got an execution time of about 0.9s to 1s for this command.  This
means, Squeak is only 7-8 times faster than Ruby for this test case.

Running the game for a 15x15 map and measuring the time with the
method described above takes 6.3s regardless whether I use a "for
0..5" or a "d=0; while d < 6" loop construct.

bye
-- 
Stefan Matthias Aust \/ Truth Until Paradox