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Subject: Re: Tablebase cache and hashtables (Fritz 7)

Author: Wylie Garvin

Date: 13:16:23 12/12/01

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On December 12, 2001 at 15:41:02, john rice wrote:

>Hello,
>Since larger hashtables increase playing strength, isn't it safe to assume
>increasing the tablebase cache would do the same? With 512m of ram available, I
>usually set the hashtable size of Fritz 7 to 128 or 256m, yet the default
>tablebase cache is only 2m. With all 3,4,5 and some 6 piece endgame tablebases
>it would seem 2m of cache would be a huge slowdown/bottleneck during the
>endgame. Any thoughts?
>Thanks,
>JR

Oh yeah--any node in the database does not need to be searched in the normal
fashion; all database positions are leaves.  If the program *could* hit the
database at all depths, then the pathological point would occur in the endgame
phase somewhere where a large fraction of leaves were database positions.  But
the situation would get better with each move played, because (a) the tree would
tend to get smaller after a while, and (b) lots of the needed positions would be
left over in the cache.

I am totally guessing here, but a size of 2mb suggests to me that Fritz7 only
goes into the database up to some number of plies (6? 8?).

wylie



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