Author: leonid
Date: 06:31:03 01/26/00
Go up one level in this thread
On January 25, 2000 at 23:50:51, Robert Hyatt wrote: >On January 25, 2000 at 21:21:53, Chris Carson wrote: > >>On January 25, 2000 at 20:56:21, Peter W. Gillgasch wrote: >> >>>On January 25, 2000 at 08:46:27, Chris Carson wrote: >>> >>>>Does anyone know what position(s) HSU used >>>>to get the 100M NPS (DB) or 200M NPS for >>>>DBII? >>> >>>Why do you think that the position matters >>>at all ? As long as he can keep the chips >>>busy the total number of cycles should be >>>constant. Since he was doing the last 4 plies >>>in hardware - and that means that he basically >>>did all the positions in hardware - I suspect >>>that the overhead onthe SP which certainly >>>depends on the position can be neglected... >>>Obvious, isn´t it ? >>> >>>-- Peter >>> >>>>Was it one position or many position's? Was it >>>>middle game, endgame, or combination? >>>> >>>>I would like to have the EPD for the >>>>position, it would be interesting to >>>>benchmark against. :) >>>> >>>>Thanks. >>>> >>>>Best Regards, >>>>Chris Carson >> >>OK, but that is not why I wanted the position. HSU >>quoted the numbers and I would like to know what positions >>were used. >> >>Best Regards, >>Chris Carson > > >I don't think _anyone_ uses positions when they quote nodes per second. IE >when I quote 800K for crafty on my quad xeon, that comes from watching a bunch >of games and noting the NPS as the games are played. It runs from as low as >550K to about 1M on my xeon. But once castled, it averages about 800K for the >rest of the game... And what are the main characteristics for "Quad Xeon" ? Quad probably stay for four processors, but how about the speed of each chip in Mhz? Leonid. >NPS is a 'vague' number since I have positions where I can hit 450K or 1.3M >depending on which one I use. Most of use use actual game numbers as a result, >although it doesn't mean a thing. > >In Hsu's case, he can't _really_ give an exact nps, because the hardware >processors don't count nodes. It would take them as long to count one as it >does to search one. He seems to have an idea that they drove the chess >processors at 50-70% utilization. Which would translate into roughly 500-700M >nodes per second, raw numbers. He also claimed 30% search efficiency, which >most likely turns into the 200M number. IE for Crafty, the raw NPS is 800K. >But due to extra work done, this is probably equivalent to 600K overall. > >I am not certain how he arrived at 200M, but that is a reasonable guess. Based >on 480 chess processors at 2M to 2.4M nodes per second. taking the lower number >(some were clocked at 20mhz, others at 24mhz) we get almost 1B nodes per second >max, but he couldn't keep them all busy. .70 * 1B = 700M. .30 * 700M = 210M, >which was the claimed speed...
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