Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Measuring NPS...

Author: Robert Hyatt

Date: 07:51:32 11/18/02

Go up one level in this thread


On November 18, 2002 at 00:55:35, Uri Blass wrote:

>On November 17, 2002 at 22:31:31, Robert Hyatt wrote:
>
>>On November 17, 2002 at 21:12:53, Joel wrote:
>>
>>>Hey All,
>>>
>>>Thankyou to everyone who responded to my query regarding 'extracting bits from a
>>>bitboard'. I think I will use some preprocessor code and use the bsf/bsr method,
>>>otherwise falling back on my old method (I can play around with this part
>>>later).
>>>
>>>My next question that follows is how do you guys measure nodes per second. I can
>>>think of a quite a few ways of doing it myself, but I would prefer implementing
>>>it in a way which lets me very confidently compare my results with others.
>>>
>>>Thanks,
>>>Joel
>>
>>
>>Every time you recursively call Search() or Quiesce(), increment a counter
>>by one.  That is counting nodes searched.  Divide that by time used and you
>>get a useful NPS value.
>
>The problem with this value is that you cannot compare it with other people
>
>I make and generate only legal moves so for me nodes are legal moves.
>You make pseudo legal moves that may not be legal when the king is not in check
>and another person may make pseudo legal move in every case.
>
>Today I update my nodes every time that I make a move that is not null move(I
>could get higher nps if I update my nodes after making null moves).
>
>I have in movei pruning that is done after I make a move.
>I can do this pruning after I call search(in the beginning of search) or before
>I call search.
>
>By your definition I get different nps in both cases.
>
>Uri


Depends.  A node is a "position reached".  If you prune _before_ making a move,
then
you didn't reach that position.  If you make a move and then prune you _did_
reach a new
position.

Of course comparing nps between two programs is not particularly informative...




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.