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Subject: Re: crafty question !! (to bob mainly)

Author: Robert Hyatt

Date: 12:23:44 07/07/00

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On July 07, 2000 at 12:33:10, pavel wrote:

>about position.lrn
>
>
><snip>
>
>Crafty now has a permanent hash table that is kept from game
>to  game. A position gets into this hash table when a search
>value is significantly lower than the last search value. The
>permanent hash table can hold up to 65536 positions. Once it
>fills up, the positions are replaced on a FIFO basis, always
>keeping the most recent 64K entries. Each time Crafty starts
>a search, the positions  and  scores  from  this  table  are
>stuffed into the normal transposition table, and used during
>the search just like any other table entry.
>
>from the crafty ftp site (under crafty.doc)
>
>so it means that the position.lrn file doesnt get larger than 64000 entries. ;(.
>and its a default setting.
>why is it done ? I mean why is it restricted to only 64k?
>Is it possible to make it infinite? ( no size restriction)
>Is there a certain code that needs to be changed to overcome this problem,
>I would graetly appreciate your help. :)
>thanks
>Pavel


This is not intended to be 'permanent'.  Think about the casual user...  the
position.bin file would grow and grow, and eventually reach the size of the
_real_ hash table.  Now you have a _big_ problem as all the hash entries would
be marked 'never overwrite'...

You can easily modify LearnPosition() (in learn.c) to increase this limit.  I
don't think it will help a thing...



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