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. >>>>>> >>>>>>-- >>>>>>GCP >>>>> >>>>>I did not ask about single example from endgame but about >>>>>the middle game or about rating improvement. >>>>> >>>>>Uri >>>> >>>> >>>>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. >>> >>>Uri >> >>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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