Author: Robert Hyatt
Date: 14:48:07 09/25/01
Go up one level in this thread
On September 25, 2001 at 14:26:09, Vincent Diepeveen wrote: >On September 25, 2001 at 14:09:38, Robert Hyatt wrote: > >>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. > >Please do so on the 24 game positions as used in your Article about >Cray Blitz. Also for every depth apart. To also see possible relationships >in search depth. > >Each position for 1 hour or so. If automatically scheduled that's within >24 hours. That won't be 24 hours. The test has to be run for 1 cpu and for 4 cpus (and probably for 2 for completeness). I see no reason to worry with 1 hour searches since that can't be done in real games. In Cray Blitz, I took a real set of searches on 16 cpus and ran the same tests on 1,2,4 and 8. The 1 cpu tests took forever for obvious reasons. > >>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.
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.