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Subject: Re: Pawn Hashkey Size

Author: Sune Fischer

Date: 12:07:40 12/03/01

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On December 03, 2001 at 14:23:44, David Rasmussen wrote:

>>There is a common misconception that collisions are so
>>evil that they will automatically weaken your program
>>when they happen. That is totally false.
>>
>
>I understand that, but the speed gain isn't that big from 64 bits to 32 bits,
>and while collisions might not themselves be evil, the increase in complexity of
>debugging etc. sure is. A very important invariant, that a position's
>pawnstructure is always evaluated the same way, doesn't hold. I don't like that
>for a small speed gain. But sure, it's a design choice.
>
>/David

In a typical game I seem to be getting around 5000-10000 different pawn
positions.
With 32 bit keys I would expect 1 collision for every 100 games, of cause once
there is a collision it could be serious because the score is used so often.

-S.



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