Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: digressing with some advanced maths !

Author: Robert Hyatt

Date: 11:12:46 10/18/04

Go up one level in this thread


On October 18, 2004 at 11:40:55, GeoffW wrote:

>Hi Bob
>
>Thanks for the help, just trying to digest some of your other points, but this
>one just made me smile in relation to you first comment
>
>>>I am using SEE to order the capture moves in my Q search.
>>>Move ordering in the normal search is still MVVLVA as my SEE is quite slow
>>
>>This is backward thinking.  Look at how many qsearch nodes there are vs the
>>non-qsearch nodes.  Yet you are using your "slow SEE" where you use it far more
>>often than if you used in in non-qsearch only.  :)
>
>I was just testing a position with and without SEE changes
>
>I do keep a count of nodes and qnodes, but must admit I havent really studied
>the relative percentages very much so dont have a very good feel for it.
>I then looked at the stats output line
>
>11+    15   2146   26800500   f4c7
>11+   315   2159   26959969   f4c7
>11   9977   5979   92721403   f4c7 c8c7 c3b5 c7b8 d1d8 e8d8 e3f4 g4e5 f4e5 b8a8
>b5c7 a8b8 c7a6 b8a8 a6c7 a8b8 c7d5 d8d6 e5d6 b8a8 d5b6 a7b6 c1a1
>
>Computer's move: f4c7
>
>Nodes=92,721,403  Quiescent Nodes=48,694,293   Qnodes Percent=6.0%
>
>Note my very low Qnodes percentage, and the slight rounding error. Cough !!
>
>Fixed that now, silly 32 bit overflow problem, but I have even less feel now for
>typical ratios of qnodes/nodes.
>
>I guess the point you are making is that qnodes are large in relation to nodes.
>
>   Geoff

Correct.  IE your first call to quiesce() is mandatory, and there will be as
many "first calls" as there are total non-q-search nodes roughly.  IE you spend
way  more time in the q-search than in the normal search.  That has to be where
you worry about efficiency...




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.