Author: Robert Hyatt
Date: 08:24:44 03/27/01
Go up one level in this thread
On March 27, 2001 at 08:00:44, Vincent Diepeveen wrote: >On March 26, 2001 at 22:47:24, Robert Hyatt wrote: > >>On March 26, 2001 at 21:52:16, Vincent Diepeveen wrote: >> >>>On March 26, 2001 at 21:35:51, Christophe Theron wrote: >>> >>>>On March 26, 2001 at 20:06:21, Vincent Diepeveen wrote: >>>> >>>>>On March 26, 2001 at 18:49:47, Christophe Theron wrote: >>>>> >>>>>>On March 26, 2001 at 18:35:17, Frank Quisinsky wrote: >>>>>> >>>>>>>Hi Christophe, >>>>>>> >>>>>>>a very interesting and good message, like that ! >>>>>>> >>>>>>>Now a little bit in my superb English :-)) >>>>>>> >>>>>>>01. I believe you forget the important factor, that you can playing engine - >>>>>>>engine matches on a dual system with ponder! An interesting player must not buy >>>>>>>a second computer and an autoplayer. >>>>>> >>>>>> >>>>>>I do not disagree, but my post was about the increase in playing strength from a >>>>>>dual system. Maybe it was directed more at those who think that they are going >>>>>>to crush everybody on the chess servers with an expensive dual system. :) >>>>> >>>>>I think those persons are not completely insane then, because >>>>>in blitz programs search to very shallow depths. Especially the so called >>>>>3 0 matches which are popular (i personally never play with diep 3 0 >>>>>against other engines as i don't care about that level as debugging >>>>>such a game costs me more time as the game itself costs for sure, not >>>>>to mention that the scores scroll too quick on my screen with 3 0 and >>>>>the shallow depths make the game not very serious representing tournament >>>>>level). >>>>> >>>>>Most people who are running a prog on a chess server kick only on dick >>>>>height. In that respect a dual is a good thing for them. As in blitz it's >>>>>not 20 points or so it's more like 150 to 200 rating points at least >>>>>difference. >>>> >>>> >>>>Your 150 to 200 elo figure is nonsense. >>> >>>I remember the first duals coming into ICC. >>>Ratings jumped up. DIEP got completely annihilated by crafty >>>when they arrived. >>> >>>Nonsense? >>> >>>Your words! >>> >>>Diep single cpu 450PII 6 ply in blitz. >>>Diep dual 800 cpu 8-9 ply blitz. >>> >>>Pick the rating difference... >>> >> >> > >PIII core is nearly 18% faster as a PII core for DIEP. > >More hashtables etcetera. > >The comparision is never fair of course. I had a 450PII 128mb RAM >then bought a dual 256MB PIII800. > >That's how one must compare, *not* same Mhz versus same Mhz! That simply produces gross errors based on different assumptions. IE if you compare program X on a single CPU Y with program A on a multiple CPU B machine, you have _lots_ of reasons why A is better than X. A is faster due to the multiple cpus. A is faster due to the fact that CPU B is faster than CPU Y. A is faster due to a faster bus on B than on Y. There is simply too many variables. I _always_ talk about parallel speedup as using one of cpu X, versus 2 of cpu X. So that the _only_ variable is the number of CPUs. The mhz is identical, as is cache, as is hash table size, etc. One degree of freedom lets you attribute an improvement to that one difference. If you have multiple degrees of freedom you can't do that. Your program might actually be worse on 2 cpus than on 1, but because you use 2 _better_ cpus, it does better than it does on the poor 1 cpu platform. This is what correlation analysis is all about in statistics... and it has a significant error rate for cases with > 1 degrees of freedom. With exactly 1 degree of freedom, the only error is in the actual sampling data itself, not in attributing success or failure to one of several features that change together. > >>I don't quite see how you get 2-3 more plies from a dual 800 over a single >>450, nor do I understand why you compare the dual 800 to the single 450. On >>a pure mhz basis, you are comparing 1600 to 450, which is almost a factor of >>4. I can see 1+ plies with a factor of 4. I can't see 2-3 unless you are >>talking simple endgames... >> >> >> >> >>>> >>>> >>>> Christophe
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