Author: Robert Hyatt
Date: 14:52:02 07/25/00
Go up one level in this thread
On July 25, 2000 at 15:51:30, Ed Schröder wrote: >On July 25, 2000 at 14:39:59, Robert Hyatt wrote: > >>On July 25, 2000 at 11:15:45, Ed Schröder wrote: >> >>>On July 25, 2000 at 10:44:20, Chris Carson wrote: >>> >>>>On July 25, 2000 at 10:19:10, Ed Schröder wrote: >>>> >>>>>On July 25, 2000 at 08:44:57, Dave Gomboc wrote: >>>>> >>>>>>- the "1 million nodes/sec" figure is a peak figure, not an average >>>>>> - average is 200k nodes/sec >>>>> >>>>>From the IBM site (may 1997): >>>>> >>>>> "Deep Blue was now capable of examining and >>>>> evaluating an average of 100 >>>>> million chess positions per >>>>> second." >>>>> >>>>>Ed >>>> >>>>Thanks Ed! Accurate and factual as always. :) >>> >>>Somewhere else the 200M is mentioned (as a peak?). The text also mentions >>>DB doing some pre-processor stuff (I think). >> >>This is all scrambled. Here are the right numbers: >> >>single chip: 2M or 2.4M nodes per second. >> >>DB2 (1997 Kasparov match): >> >>480 chess chips, half at 2M, half at 2.4M nodes per second. 1B nodes per >>second peak, 700M nodes per second actually searched, roughly 70% of those >>nodes are often referred to as "search overhead" reducing the effective NPS >>for DB2 to 200M. DB1 (1996 Kasparov match) searched 100M effective nodes per >>second... >> >>Those are straight from Hsu, so I feel pretty sure they are right... The others >>are smeared across a time line that contains DB1 _and_ DB2... Where DB2 was >>2x faster + move eval. > >The IBM pages say 256 processors and not 480. How come that Hsu's >informations don't correlate with IBM's all the time? I have no idea where you are looking. 256 was the 1996 DB. 1997 DB had 480. This number is on IBM's web site... Maybe you are reading something written in 1997, but prior to the DB2 match being played. Until right before the match, I didn't know that DB2 had 480 processors either, until I heard it from the horse's mouth... > >And now we have a new item. It was not 200M nodes but suddenly it is >1000M nodes said by Hsu. Again it contradicts the IBM pages you know. > >Maybe you should not use the name of Hsu so much speaking on his behalf. > I have answered this already. If you multiply 480 * 2.2M, you get the theoretical peak NPS that DB can search. Hsu said that he keeps the chess processors running at about 70% of capacity due to the speed of the processors vs the speed of the SP nodes. After that, he claims 30% efficiency on the parallel search. If you compute 480 * 2.2M * .7 * .3, you get 200M, which is the efficiency figure he has _always_ quoted. but that is not the same as everybody else is reporting RAW NPS in parallel programs. My raw NPS in Crafty is 1M. My actual efficiency is .8 roughly. But since the efficiency varies, I don't try to correct the NPS reported because I can't do this very easily. Hsu simply reports the 'pessimistic typical value' and lets it go at that. Does that explain this??? > > > >>>Quote: >>> >>> "Deep Blue uses "live" software that can actually generate up >>> to 200,000,000 positions per second when searching for >>> the optimum move. The software begins this process by >>> taking a strategic look at the board. It then computes >>> everything it knows about the current position, integrates >>> the chess information pre-programmed by the development >>> team, and then generates a multitude of new possible >>> arrangements. From these, it then chooses its best possible >>> next move." >>> >>>Ed >>> >> >>Sounds like something written for the general public, by someone that didn't >>have any idea of how a computer plays chess in general. IE someone in a P/R >>department writing about something he "thinks" he understands. The words sound >>good. The paragraph is nearly meaningless.. > >"Sounds like..." > >"The paragraph is nearly meaningless......" > >"IBM P/R people are stupid......" > >Be careful, IBM might sue you one day :) > >Ed > > I didn't say they were "stupid". I said it was written by a P/R type person, intending it for the masses. Not the technical folks. To me it reads like gibberish. To a non-computer person, it probably sounds great (if meaningless). > >>> >>> >>>>Best Regards, >>>>Chris Carson >>>> >>>>> >>>>>> - you will have to verify for yourself if that figure is for one chip or more >>>>>>- whether db uses forward pruning or not is obviously not clear >>>>>> - bob says it doesn't >>>>>> - article i read implies it does >>>>>> - db logs also imply it according to ed >>>>>> >>>>>>Dave
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