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Subject: Re: Questions about Nimzo8 and its proprietary endgame tablebases.

Author: Robert Hyatt

Date: 19:34:44 12/22/00

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On December 22, 2000 at 16:52:52, Alexander Kure wrote:

>On December 22, 2000 at 15:21:09, Robert Hyatt wrote:
>
>>I wanted to say 5 times.  But somehow I convinced myself that it was actually
>>3/256, since we normally store 256 unique states per entry, and only need
>>3 states for w/l/d.
>>
>>Your number means we would need about 1.5 gigs of memory to hold all the
>>3-4-5 piece w/d/l files.  Not going to happen on my machines.  :)  Not worth
>>it.
>>
>>The error I made was a simple one.  Probably due to the late hour and advanced
>>age.  :)
>>
>>Thanks for watching carefully.  Need to keep me straight when I wander.  :)
>
>Hi Bob,
>
>You do not need to hold *all* of the 5 pieces endgames in RAM, only the most
>interesting.
>E.G. in London i used 2 pawns vs rook and rook + pawn vs. rook.
>This summed up to an additional 200 MB. Not a big deal.
>
>Greetings
>Alex


Right.  But a good while back I ran a bunch of tests, keeping up with which
files I wanted to probe in the search.  I didn't find any particular "winners".
IE if I was in a KRPP vs KRP, then KRPvsKR was a winner unless the pawn is
close to promoting.  But for normal positions, I found the TB hits scattered
"all over" the landscape.  I think that if I had this on my to-do list, I would
probably demand-load the files as needed.  Or I might simply keep a log of what
I probe during a search, then load all those w/l/d databases before the next
search...  and if I complete a search without hitting any I have already loaded,
I would probably dump them...

However, with good cache strategy, storing the TB hits in hash, and being
careful when/where I probe, I really don't plan on doing w/l/d right now...



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