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Subject: Re: [DB] Some data from the logfiles

Author: Robert Hyatt

Date: 21:32:17 08/24/02

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On August 24, 2002 at 19:04:31, Uri Blass wrote:

>On August 24, 2002 at 18:12:45, Robert Hyatt wrote:
>
>>On August 24, 2002 at 16:19:53, Uri Blass wrote:
>>
>>>On August 24, 2002 at 16:07:05, Alvaro Jose Povoa Cardoso wrote:
>>>
>>>>On August 23, 2002 at 09:46:04, Uri Blass wrote:
>>>>
>>>>>On August 22, 2002 at 21:42:41, Robert Hyatt wrote:
>>>>>
>>>>>>On August 22, 2002 at 16:09:07, Uri Blass wrote:
>>>>>>
>>>>>>>On August 22, 2002 at 15:51:28, Jeremiah Penery wrote:
>>>>>>>
>>>>>>>>On August 22, 2002 at 06:47:34, Gian-Carlo Pascutto wrote:
>>>>>>>>
>>>>>>>>>That does not make sense - it only does when you take the first number as
>>>>>>>>>the nominal ply depth and the second number as the part of that that was
>>>>>>>>>done by the hardware searches.
>>>>>>>>
>>>>>>>>
>>>>>>>>So what does it mean when you have searches like this,
>>>>>>>>
>>>>>>>>-->  17.   Be3 <-- 23/113:12
>>>>>>>>---------------------------------------
>>>>>>>>Guessing Qc7
>>>>>>>> 3(4) 25  T=0
>>>>>>>>qd1d2 Pc5c4 pb3c4P
>>>>>>>> 4(5) 25  T=0
>>>>>>>>qd1d2 Pc5c4 pb3c4P
>>>>>>>> 5(5)[Qd2](25) 25  T=1
>>>>>>>>qd1d2 Pc5c4 pb3c4P
>>>>>>>> 6(5)[Qd2](25) 25  T=2
>>>>>>>>qd1d2 Pc5c4 pb3c4P Qc7c4p
>>>>>>>> 7(5) #[Qd2](28)##################################### 28  T=4
>>>>>>>>qd1d2 Re8b8 nf3e5P Pd6e5n
>>>>>>>> 8(6) #[Qd2](28)##################################### 28  T=12
>>>>>>>>qd1d2 Re8b8 bc2d3 Pa6a5 pc3c4
>>>>>>>> 9(6)<ch> 'ng6'
>>>>>>>>---------------------------------------
>>>>>>>>--> Ne7g6 <--
>>>>>>>>---------------------------------------
>>>>>>>> 28  T=19
>>>>>>>>qd1d2
>>>>>>>> 3(4)[Qd2](30) 30^ T=1
>>>>>>>>qd1d2 Pc5c4 pb3c4P Pb5c4p
>>>>>>>> 3(5) 35  T=1
>>>>>>>>qd1d2 Qd8c7 pb3b4 Pc5c4 be3h6P
>>>>>>>> 4(5) 35  T=1
>>>>>>>>qd1d2 Pa6a5 pa2a3
>>>>>>>>
>>>>>>>>
>>>>>>>>where you have depths like 3(4)?  They can't have 3 nominal plies, where 4 of
>>>>>>>>those plies come from the hardware, because obviously that's impossible.
>>>>>>>
>>>>>>>A good question.
>>>>>>>
>>>>>>>I do not understand the meaning of the second mnumber
>>>>>>>but the first number is clearly the brute force depth based on their paper.
>>>>>>>
>>>>>>>Maybe the second number is about some limit about the extensions but OI do not
>>>>>>>know.
>>>>>>>
>>>>>>>Uri
>>>>>>
>>>>>>The second number doesn't vary enough to be relevant to extensions.
>>>>>
>>>>>It is clearly not the maximal number of plies for extensions  but it may be
>>>>>relevant to extensions.
>>>>>
>>>>>Uri
>>>>
>>>>
>>>>Could it be the minimum number of plies for extensions, witch translates to the
>>>>maximum number of plies for brute force?
>>>>
>>>>Alvaro
>>>
>>>No
>>>
>>>It cannot be brute force additional search because we know that the average
>>>brute force depth was only slightly more than 12 plies.
>>>
>>>Uri
>>
>>
>>Again, we don't _know_ any of this.  The hardware did some unusual things,
>>including Hsu's quietly mentioned futility pruning.  They _always_ showed
>>their depth at ACM events as a two-number combination...  I have not yet
>>seen anything that says that 12(6) doesn't mean _exactly_ what the team
>>members have told me in the past.  They have always considered the
>>"software" part of the search as the important part, because that is the
>>part of the search that they worked on heavily.  The chess processors
>>are much simpler, with no hashing, etc...  In past events, when asked by
>>IM Mike Valvo during a game, "what depth are you guys searching" they would
>>typically respond "10 plies".  When he asked "is that all?" Hsu would add
>>"We are doing another 4 plies in the hardware."
>
>In the paper it was claimed that iteration x means x-4 plies in the software and
>4 plies in the hardware.
>
>Uri


Correct.  But the paper _also_ says that the tests were run on deep blue
junior, a single SP2 processor with 24 chess processors rather than the usual
16.  I could see why adding more processors would result in a ply less being
done in the hardware, for the balancing reasons I have explained several times
here...

Deep Blue had a different configuration, one SP2 with 16 chess procssors.  An
extra ply would probably be needed on the chess processors or they would out-run
the SP2 and the SP2 would be waiting too much.



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