Author: Ernst A. Heinz
Date: 04:48:50 11/03/98
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On November 02, 1998 at 16:27:39, Robert Hyatt wrote: > >On November 02, 1998 at 09:49:34, Ernst A. Heinz wrote: > >>On November 02, 1998 at 08:24:08, Robert Hyatt wrote: >>> >>>On November 02, 1998 at 02:49:14, Koen van Dijken wrote: >>> >>>>mr Hyatt, >>>> >>>>I was comparing the speed in nps of my own program against that of Crafty. I >>>>have the sources for 14.2 and 15.20. I noticed that in Search there is a >>>>difference in node counting between 14.2 and 15.20. In 14.2 you do not count >>>>illegal moves, in 15.20 you do. Is there a reson for this? >>>> >>>>15.20 >>>> } else tree->nodes_searched++; >>>> UnMakeMove(tree,ply,tree->current_move[ply],wtm); >>>> >>>>Is this maybe the way nodecounting is done in other programs as well, for >better >>>>comparising? >>>> >>>>Koen van Dijken. >>> >>> >>>That was the main idea. However it turned out to have no effect... because now >>>I increment nodes_searched at the top of search, and I *never* get there unless >>>the position is "legal"... so for search() it doesn't matter. In quiesce, I >>>do count illegal positions... but the point is counting "work" really... and if >>>I do a MakeMove() and so forth, I "searched" that node whether it was legal or >>>not. >> >>We do *not* count illegal positions for our NPS numbers. >> >>IMO counting illegal positions is not a good idea because they require so much >>less work than legal nodes. Actually, there is not much to do beside >>make/unmake move at illegal nodes. >> >>=Ernst= > >What about in the quiescence search? Do you cull illegal captures before >making them? Some yes, some not. >Or not count them when you notice they are illegal. Exactly -- we do not count them although we called "expand_node" and made the move. This way your NPS number goes up if you generate less illegal moves. >I think >counting or not-counting makes little difference overall since in my case, >the number is already "mixed" since normal search weeds illegal moves out >while the q-search does not... If you do not count illegal positions you can actually measure the improvement made by generating less of them (see above). BTW, do you roughly know how many of your reported nodes are illegal ones? =Ernst=
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