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Subject: Re: About qsearch...

Author: Sune Fischer

Date: 01:14:40 12/30/01

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On December 29, 2001 at 20:19:45, Uri Blass wrote:

>>I think R. Hyatt said crafty spends 50% of the time in QS.
>
>I think that it includes the time that Crafty spends on evaluation function.

Yes, what else?

>>I'm not counting nodes just the time, the program just runs 3-5 times slower to
>>the same depth (for the base tree) when it does a full QS.
>
>
>It means that you probably have some bug.
>
>The program should run faster to the same depth when you do qsearch because of
>better order of moves.

I do not hash the qnodes.
But the move ordering can be improved, I know.

> I don't understand
>>why this is so unexpected, say there are two possible captures at every leaf
>>node on average after I stop my QS at depth 3. Then that alone is 3 times as
>>large a tree, and there could be more captures after that!
>
>
>There are captures that should not be analyzed because they are not good enough.
>If you are a rook down and capture a pawn when alpha=0 then you can avoid making
>the move because you can know that it is not good enough.
>
>I can guess that your problem may be that you make these captures only to
>evaluate them later and discover that they are bad.
>
>Maybe my guess is wrong and your problem is different.

I'm not sure, I'm doing exactly what Bruce has explained here:
http://www.seanet.com/~brucemo/topics/quiescent.htm

it is simple, and apparently slow.

>>BTW Christophe, are you not doing SEE at all?
>
>I think that Tom already explained in his reply to christophe that Christophe
>does DEE and not SEE.
>
>Uri

Right, it was some recursive evaluator.
Interesting though, that the strongest program around is not using SEE ;)

-S.



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