Author: Vincent Diepeveen
Date: 16:35:31 02/15/06
Go up one level in this thread
On February 15, 2006 at 19:19:07, Joshua Shriver wrote: >I thought nodecount had a strong definition already. 1 node == 1 move >possibility in the search tree. Not sure how this number could be made different >other than what the actual number is. > >Josh Well even in the case of Diep it's difficult to count like for example Fruit is doing it. In case of Diep, should i count the number of generated moves, or should i count the number of visited positions, or should i count the number of visited nodes including the number of avoided visits? You know there is a huge difference there. Let me give you an example. At a simple outdated K7 the number of generated moves a second in search is 2.2 million a second. That doesn't include a fast searcher of mine which generates effectively at 6 million a second. But let's show a huge difference between the fast searcher and diep already in terms of counting nps. The fast searcher is detecting a repetition in top of the search. So that counts as a node. In diep it isn't counted as i detect the transposition already directly after making the move, so before doing another iteration (diep is not recursive). In most programs after making an illegal move, the king gets captured. In diep this is highly unlikely to happen. It will never search an illegal position. Usually it detects illegal moves directly after making a move as my incremental attacktables give it already. Of course in the fast searcher, just keeping track of incremental attacktables is already too expensive, as it is searching at 3 million nps (K7 2.1Ghz) and quite a bit more at A64. This is a huge difference in nps practical. The old diep had a very stable nps. If i count like the fast searcher is counting and this is how most engines count, in some middlegames i get 2.5 times more nps than diep reports now. In openings position of course repetitions and illegal positions happen less, so obviously the increase in nps there is pretty tiny but still significant in absolute numbers. It's more like 30% there. Not 250%. Yet on average the increase is 50-60% in a game in nps on average. That's quite significant. Vincent
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.