Author: Robert Hyatt
Date: 10:34:04 10/11/98
Go up one level in this thread
On October 11, 1998 at 12:20:55, blass uri wrote: > >On October 11, 1998 at 10:35:41, Robert Hyatt wrote: > >>On October 11, 1998 at 03:27:59, blass uri wrote: >> >>> >>>On October 11, 1998 at 00:17:55, Robert Hyatt wrote: >>> >>>>On October 10, 1998 at 14:51:56, blass uri wrote: >>>> >>>>>I think it is possible to save space by storing only win,draw,loss in these >>>>>tablebases >>>>>when you go to the position with 4 pieces you can generate the tablebase >>>>> >>>>>Maybe it is not practical for blitz but it can be practical for tournament time >>>>>control. >>>>> >>>>>Uri >>>> >>>>I would not want to generate either KBNK or KQKR on the fly... because >>>>I probe *in* the search, and need the result then, not just at the root. >>> >>>You will have the result because I did not say not o have the result of >>>win/draw/loss >>>>And KQKR can't be built in a couple of minutes by anybody yet... the 3-4 >>>>piece files take 3-4 *hours* to build, in total... >>> >>>It is not important to build all the 3-4 pieces files but only the KQKR when you >>>get to the KQKR endgame and you can save it in the ram and not in the harddisk >>>so you are faster. >>> >>>I read that before some years(I think in 1989 but I am not sure) a 6 pieces file >>>was generated by a computer by 6 hours and it found mate in more than 200 in a >>>position of KRBvKNN or something similiar(it was done by a super computer andnot >>>by a personal computer but personal computers are today better) >>> >> >> >>this was done, but on a 50 million dollar computer. Which is not going to >>be available to any of us in a tournament... nor will the PC catch up to >>the speed of that machine for 20-30 years... > So there's no use planning on >>being able to compute even a 5 piece file. IE KRP KR takes 80 hours plus >>on a machine faster than a PC today (big alpha machine). >>compute the promotion classes which take 12-24 hours each to build. > >I understand that one of the reasons for the long time is that you must use the >harddisk because you have not enough ram. > >In KQvKR you have only less then 3,000,000 positions if you assume that the >white king is in a1,a2,a3,a4,b1,b2,b3,c1,c2,d1 so you can store all the >information in the RAM >Does it help to generate the tablebases faster? > >Uri > it isn't about the "total positions".. that determines the size of the database... it is about the total paths to reach each of those positions, which requires a 60+ ply search to resolve. This is why it takes time, even starting from mate in 0 positions and retrograding backward takes a lot of time... time that is too long for a typical 3-4 minute per move search.. > >> >>>Some quesions: >>> >>>1)Is it possible to do it in personal computers if you have no problem of time? >> >> >>yes until you add the "no problem of time." To compute the files needed to >>to do KRP vs KR would take way over a week on the best PC around today... >> >> >> >>> >>>2)How much memory was used by the supercomputer to build the table? >>> >> >>many gigabytes... But even worse, 65536 CPUs were used... >> >> >> >>>Uri
This page took 0.01 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.