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Subject: no more comments???

Author: Robert Hyatt

Date: 20:12:15 07/22/02

Go up one level in this thread

On July 21, 2002 at 14:56:12, Robert Hyatt wrote:

>On July 21, 2002 at 14:54:18, Robert Hyatt wrote:
>>On July 21, 2002 at 01:29:38, Uri Blass wrote:
>>>On July 20, 2002 at 22:20:29, Robert Hyatt wrote:
>>>>On July 20, 2002 at 05:55:43, Uri Blass wrote:
>>>>>On July 20, 2002 at 05:47:38, Gian-Carlo Pascutto wrote:
>>>>>>On July 20, 2002 at 02:52:11, Uri Blass wrote:
>>>>>>>My question was not about comparing using hash tables
>>>>>>>and not using hash tables but about comparing using hash tables
>>>>>>>in the normal way and using hash tables
>>>>>>>for all purposes except pruning.
>>>>>>In the example given, the move ordering from hashtable is almost
>>>>>>irrelevant, so all the gains are due to pruning.
>>>>>I did not ask about single example from endgame but about
>>>>>the middle game or about rating improvement.
>>>>I gave you an answer of sorts.  Best case is fine 70.  3x as many plies.
>>>>Middlegame seems to be a factor of 2x in terms of time to reaching a specific
>>>>depth.  So a fraction of a ply.  So from early middlegame to endgame sees this
>>>>go from a fraction of a ply to (say) 30 additional plies...
>>>>The 30 is important.  It doesn't just happen in fine 70.  It happens in lots
>>>>of important king and pawn endings.
>>>I know that in simple endgames you can get big improvement thanks to using hash
>>>tables for pruning.
>>>I also know that you can get a factor of 2 in the middle game from hash tables
>>>when the comparison is between using hash tables and not using them.
>>>It did not answer my questions.
>>>Only Christophe answered them when he explained that I may get 10% speed
>>>improvement in the middle game from pruning.
>>OK... I will take my usual approach and simply give you _real_ data.
>>Three positions.  The first tactical, the second just a middlegame position
>>with no real tactics, the last an endgame (fine70).  All three searched with
>>normal hashing, and then using hashing as normal, but not allowing the hash
>>stuff to produce a fail high, fail low, or exact score.  It can still tell me
>>to avoid a null-move search.  The difference in times, then, is _totally_
>>dependent on using the hash scores only, as everything else is identical.
>>                 hashon         hashoff
>>Tactical         48 secs        78 secs
>>normal          118 secs       183 secs
>>fine 70           0 secs        58 secs
>>In fine 70, both searched to 18 plies.  hash on got right move (kb1
>>winning a pawn).  hash off did not get right move.
>>You can draw your own conclusions.  10% is obviously _way_ too low.  I
>>said roughly a factor of two, for middlegames, which is pretty close in
>>the first two.  In the last position we _know_ what hashing does.
>I should add, if you _really_ don't think that I answered your question, then
>maybe the question you actually _asked_ and the question you _meant_ to ask
>are not the same thing.  I believe my previous post shows that I _did_
>directly answer the question you asked.  _exactly_...

I find it interesting that I answer the question, get accused of not answering
the question, then I post _real_ data showing that I answered the question, and
the discussion stops cold...

why would that be???

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