Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: NullMove efficiency

Author: Matthias Gemuh

Date: 00:47:55 12/06/03

Go up one level in this thread


On December 05, 2003 at 18:49:37, Matthew McKnight wrote:

>On December 05, 2003 at 18:31:34, Matthias Gemuh wrote:
>
>>
>>
>>
>>The ratio nullmove_cutoffs / main_search_moves_searched is only 15%...20%
>>in my program. Is this extremely low ?
>>My BigLion searches at miserable 180 kN/s on 2.6GHz.
>>
>>/Matthias.



>
>I count nullmove_cutoffs/null_move_tries, and I think I get around 65%.  I'd
>guess that 15-20% with your calculation is comparable, if not better than mine.
>

Calculated that way, I also get about 65%. This can be raised to even 80%
if you evaluate each internal node.



>180 kN/s is not bad if you are doing a lot of work in eval, or other things that
>slow you down, as long as you are compensated.  With BigLion's performance, I'd
>say you are succeeding here.

BigLion indeed has a heavy eval (as eval.prm suggests), but even with only
piece square tables, BigLion remains slower than 250 kN/s.
Maybe I shall one day find a speed bug.


>I have driven myself crazy trying to increase nps,
>but I find that simple improvements to search and eval seem to increase my ELO
>the most.

I don't think Dorky 4.0 still needs improvements ;).



Here is an example:  if your program runs a factor of x slower than
>crafty on the same hardware, then find some hardware that is x slower than
>yours.  Run Crafty or Ruffian on the slow machine, and see if BigLion can win at
>approx. the same nps...

This should be possible under Fritz8 GUI on one computer. I shall try it.


/Matthias.














This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.