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Subject: Why hide the qsearch?

Author: enrico carrisco

Date: 12:18:22 01/01/06

Go up one level in this thread

On January 01, 2006 at 11:11:51, Robert Hyatt wrote:

>On January 01, 2006 at 06:12:31, Uri Blass wrote:
>>On January 01, 2006 at 05:24:30, Alessandro Damiani wrote:
>>>On January 01, 2006 at 02:36:28, Uri Blass wrote:
>>>>On December 31, 2005 at 20:50:30, Vincent Diepeveen wrote:
>>>>>On December 31, 2005 at 20:20:47, Greg Simpson wrote:
>>>>>>Vasik had very logical and persuave ideas.  I particularly liked the point that
>>>>>>trading one third speed searching for twenty times the evauation per position
>>>>>>almost has to be good if done right.
>>>>>If that describes what he's doing then it seems however Vasik has taken the
>>>>>other way around, the junior way. The utmost minimum of knowledge in leafs.
>>>>I do not understand this comparison.
>>>>Rybka is a slow searcher and Junior is a fast searcher.
>>>>What is the reason that you think that rybka has minimum of knowledge in leafs?
>>>How do you know Rybka is a slow searcher? Just by looking at its obfuscated
>>>nps?? For instance, in
>>>[D]8/8/pppppppK/NBBR1NRp/nbbrqnrP/PPPPPPPk/8/Q7 w - - 0 1
>>>do you really think it takes quite long to find the mate in 1 because of a huge
>>>static analysis? ;)
>>In this case it does not show nodes per second but in the following position
>>it shows nodes per second
>>[D]8/8/pppppppK/NBBRQNRp/nbbrqnrP/PPPPPPPk/8/8 w - - 0 1
>>Analysis by Rybka 1.0 Beta 32-bit:
>>  +-  (2.46)   Depth: 3   00:02:22
>>  +-  (2.46)   Depth: 4   00:03:01
>>1.dxe4 dxe5
>>  +-  (2.46)   Depth: 5   00:05:22
>>1.Qxd4 Qxd5
>>  +-  (2.77)   Depth: 5   00:06:16
>>1.Qxd4 dxc5 2.Qxe4
>>  +-  (3.06)   Depth: 6   00:08:19  4kN
>>1.Qxd4 dxc5 2.Qxe4 Bxd5
>>  +-  (3.06)   Depth: 7   00:12:59  18kN
>>(,  01.01.2006)
>>For some reason it searches only 4000 nodes in 499 seconds.
>>This really seem strange that static analysis takes so much time
>>I could believe 100,000 nodes per seconds on My A3000 and even 10,000 nodes per
>>seconds but less than 10 nodes per second is even too much for me to believe.
>>It seems that Vasik searches many nodes in what he counts as nodes.
>>Maybe he is using different function and not using his normal makemove in the
>>qsearch but it is clear that he searches a lot of legal moves inside of what he
>>considers as evaluation so I cannot consider it as evaluation.
>>I think that static analysis can consider trapped pieces so you can consider
>>some moves without making them to check for trapped pieces but what I see in
>>rybka is clearly too much for what I consider as static analysis.
>>I think that recursive search of moves with more than one move per side cannot
>>be considered as part of the evaluation.
>Were I guessing, I'd guess there is no counting of any kind for q-search nodes.
>And if he uses a search to sort the ply-1 move list (as I do) then that search
>(captures-only) is huge for this position, before I even get to the iteration-1
>search depth.


Of course, but why hide (not count) the qsearch?  Maybe pretending to be a slow
search implies more knowledge which makes people think that is where all the
strength is coming from. Or something else?



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