Author: Robert Hyatt
Date: 11:09:38 09/25/01
Go up one level in this thread
On September 25, 2001 at 11:24:16, Vincent Diepeveen wrote: >On September 25, 2001 at 09:56:52, Robert Hyatt wrote: > >>On September 25, 2001 at 07:28:17, Vincent Diepeveen wrote: >> >>>On September 25, 2001 at 00:40:53, Robert Hyatt wrote: >>> >>>>On September 24, 2001 at 23:45:30, Dave Gomboc wrote: >>>> >>>>>On September 24, 2001 at 22:30:26, Vincent Diepeveen wrote: >>>>> >>>>>>Hello, >>>>>> >>>>>>Here written down speedups as claimed by a guy called R. Hyatt >>>>>>by cray blitz for 24 different positoins as they occured in >>>>>>a game: >>>>>> >>>>>>pos speedup >>>>>>1 2.0 >>>>>>2 2.0 >>>>>>3 2.0 >>>>>>4 2.0 >>>>>>5 2.0 >>>>>>6 2.0 >>>>>>7 1.9 >>>>>>8 2.0 >>>>>>9 2.0 >>>>>>10 2.0 >>>>>>11 2.0 >>>>>>12 1.9 >>>>>>13 1.9 >>>>>>14 2.0 >>>>>>15 2.0 >>>>>>16 1.9 >>>>>>17 1.7 >>>>>>18 1.8 >>>>>>19 2.0 >>>>>>20 2.0 >>>>>>21 2.0 >>>>>>22 1.9 >>>>>>23 2.0 >>>>>>24 2.0 >>>>>>avg 2.0 >>>>>> >>>>>>So YOU, Robert Hyatt, claims in an OFFICIAL magazine, >>>>>>called ICCA journal march 1997, >>>>>>an AVERAGE speedup of 2.0 with cray blitz at 2 processors. >>>>>> >>>>>>Now i claim the same with DIEP if i'm not using dangerous >>>>>>extensions (which btw are turned on by default). >>>>>> >>>>>>It appears you hadn't turned them on either (smart guy >>>>>>to publish only speedups without dangerous extensions and only >>>>>>tell in 2001 that you hadn't turned them on). >>>>> >>>>>2.0 isn't a problem, it's >2.0 that gets people up in arms. >>>>> >>>>>Dave >>>> >>>> >>>>It isn't even 2.0... I don't have the paper handy now but I seem to recall >>>>that it was 1.9. Certainly it isn't 2.0 just by inspecting the numbers he >>>>gave... >>>> >>>>And the 4 8 and 16 processor tests were worse. But comparing them to crafty is >>> >>>When i tested with 4 i also never got > 4.0 with normal diep versions, >>>so very consequent with Cray Blitz, of course there are good reasons >>>why my speedup tests i get 2.0 in practical game >>>play at tournament level versus cray blitz 2.0 >>>in practical game play getting the same at 2 processors. >>> >>>Bob explained me quite clearly how he had done things in Cray Blitz, >>>my entire algorithm is based upon that of course! >>> >>>I am sure that if cray blitz would run on 2 faster Cray processors, >>>or simply run longer, that then all its findings will be similar to >>>my findings! >> >> >> >>Why don't you look at that JICCA article. Those _were_ long searches. >>Since I originally ran on 16 processors, I stuck with those results and >>backed up to 1, 2, 4 and 8 processors. the 1 processor searches took hours >>at times. The 2 processor tests were _not_ just 3 minute searches. They >>were huge. > >R=1, futility, 200Mhz things and most likely a relatively bad >tuned evaluation, when compared to todays standards. I have said this once. I will say it again. You can take crafty, and run some tests with R=0, R=1, R=2 and R=2-3 (or any other R values you care to try). That will _not_ affect the SMP performance in the least. The selectivity of the tree has nothing to do with the efficiency of the parallel search activity. I will be happy to post a few numbers if you want... Evaluation also has no effect on parallel search performance. You can be bad or wonderful there and have a good or bad parallel search for either. > >> >> >>> >>>>very hard because of the different approaches to almost everything from move >>>>ordering to search algorithm... >>> >>>Crafty is recursive, only when you have your own program parallel you >>>will understand what a big difference in parallel speedup this means >>>for DIEP + Cray Blitz. I do not know whether Fritz is recursive. It's >>>assembly, so perhaps Frans can somehow avoid recursive problems in assembly >>>in a smart way. >> >> >> >>I have done it both ways. The advantages to non-recursive are only programming >>issues, _not_ efficiency issues. There is nothing I could do in CB that I can't >>do in Crafty, if so inclined. I chose to avoid the extra complications for the >>moment, but it _was_ a choice, not a requirement.
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