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Subject: Re: If you like to solve easy mate...

Author: leonid

Date: 14:08:36 02/08/01

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On February 08, 2001 at 11:42:40, Pete Galati wrote:

>On February 08, 2001 at 11:31:35, leonid wrote:
>
>>On February 08, 2001 at 10:45:07, Heiner Marxen wrote:
>>
>>>On February 08, 2001 at 10:09:29, leonid wrote:
>>>
>>>>On February 08, 2001 at 09:49:16, Pete Galati wrote:
>>>>
>>>>>On February 08, 2001 at 08:21:44, leonid wrote:
>>>>>
>>>>>>Hi!
>>>>>>
>>>>>>If you like to solve easy (not deep) forced mate position, here is the one.
>>>>>>
>>>>>>[D]Nb1rkrNb/1n1pqp1b/n2qqq1n/1NNNNNNn/2BNNB2/1R2Q1R1/8/2K5 w - -
>>>>>>
>>>>>>Please, indicate your result.
>>>>>>
>>>>>>Thanks,
>>>>>>Leonid.
>>>>>
>>>>>Crafty found the mate in 8 a little bit earlier but it had it's hashtables all
>>>>>filled up, and I can't operate it at up to 96mb hashtables on my computer, so
>>>>>I'm stuck with 48 at the moment.  I never get around to mentioning, it's a
>>>>>700mhz Celeron.
>>>>>
>>>>>Pete
>>>>>
>>>>>5 piece tablebase files found
>>>>>1836kb of RAM used for TB indices and decompression tables
>>>>>EGTB cache memory = 3M bytes.
>>>>>hash table memory = 48M bytes.
>>>>>pawn hash table memory = 5M bytes.
>>>>
>>>>Simply can't detain my curiosity, what is the "pawn hash table"? Special hash
>>>>table just for pawns?
>>>
>>>Yes, for that part of the eval which is based only on the location of
>>>all the pawns (pawn structure).
>>>
>>>
>>>>Thanks for detailed decription! Sometime, some very interesting moments come to
>>>>light.
>>>>
>>>>My program found at the same depth mate but I not looked by brute force. It
>>>>could be that somebody will come with shorter mate.
>>>>
>>>>Leonid.
>>>
>>>I doubt it.  Chest says "no mate in 7" after 68.4 minutes.
>>>You all found the shortest mate:  Congratulations!
>>
>>Thanks, but I doubt very much that my program will search 7 moves in one hour.
>>It had awful branching factor and in 5 moves already went to 10 min. Selective
>>search make me feel this by solving position by easiest level (8 moves deep)in
>>18 sec. Usually it should be only split of one second for 8 moves, for that
>>search level.
>>
>>Brute force search:
>>
>>3 moves - 0.38 sec
>>4 moves - 22.3 sec
>>5 moves - 9 min 52 sec
>>
>>Leonid.
>
>Here's a paragraph from Bob's Crafty doc file related to the pawn hashtables:
>
>"23.   hash=x  and hashp=x  These commands are used to adjust
>the size of the hash tables in Crafty.   hash  modifies  the
>size of the transposition/refutation table, while hashp mod-
>ifies the size of the pawn structure/king safety hash table.
>The  sizes  may be entered as one of the following two types
>of values: nnnK where nnn is an integer indicating how  many
>Kbytes Crafty should use for this hash table; nnnM where nnn
>is an integer indicating how many Mbytes Crafty should  use."
>
>Pete

Thanks, Pete!

Now I see that Crafty code should be completely different from everything that I
have in my program. Difference is everywhere! The first impression I had when
I looked into Kerrigan description and he said me that its code is "like usual".

Leonid.



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