Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: are you saying deep blue cleared hash with every move

Author: Vincent Diepeveen

Date: 05:39:13 09/09/01

Go up one level in this thread


On September 08, 2001 at 23:18:09, Robert Hyatt wrote:

>On September 08, 2001 at 14:02:41, Vincent Diepeveen wrote:
>
>>On September 08, 2001 at 13:53:03, K. Burcham wrote:
>>
>>Yes it had to, because it was a preprocessor program,
>>perhaps it didn't clear 'best move' entries in the software.
>
>
>This is not a given.  You can be a pre-processor without clearing the hash
>between _every_ pair of moves.  You only need to clear the hash scores if you
>change some of the evaluation weights.  Nothing says a pre-processor has to
>do this after each move.  Early versions of crafty did some pre-processing, but
>only at two distinct places in the game, namely on the transition between
>opening to middlegame and middlegame to endgame.  That resulted in _exactly_
>two hash table clear operations in a game.  I see no reason why your assumption
>has to be valid at all.

the important thing is that it didn't use hashtables at all in
hardware and that it of course couldn't use transposition entries from
a previous search. Obvoiusly you don't need to clea rit, but practically
it comes down to the same thing.

If you can't use search scores from a previous search, then in human
eyes it is completely justified to say that this sucks bigtime!

>
>
>>
>>Note that it didn't use hashtables onboard of each hardware
>>cpu either.
>>
>>>
>>>
>>>
>>>
>>>i assume deep blue had some type of memory storage for eval
>>>    of previous lines searched. if it did are you saying  that
>>>       deep blue cleared its memory (hash), with each move?
>>>
>>>if it did not clear its memory with each move then your seven
>>>   second search limit does not make sense to me.
>>
>>>and can you tell me which game this move was taken from, so that i
>>>  can get a better analysis of this position. i can find it, but you
>>>    can save me a lot of time, if you will.
>>>
>>>i will post my results after the analysis of this position.
>>>
>>>kburcham



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.