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Subject: Re: What is the public's opinion about the result of a match between DB and

Author: Robert Hyatt

Date: 07:06:31 04/25/01

Go up one level in this thread


On April 25, 2001 at 08:42:55, Vincent Diepeveen wrote:

>On April 24, 2001 at 20:30:25, Robert Hyatt wrote:
>
>>On April 24, 2001 at 13:59:03, Vincent Diepeveen wrote:
>>
>>>On April 24, 2001 at 13:37:02, Robert Hyatt wrote:
>>>
>>>>pa4b5P Pa6b5p ra2a6 Nd6b7 bc5e3 Nb7d6 ra6a7 Bf8e7
>>>> 9(6) #[axb5](49)#################################### 49  T=55
>>>>pa4b5P Pa6b5p ra2a6 Nd6b7 bc5b6 Ra8a6r ra1a6R Nb7d6
>>>>10(6) #[axb5](49)##################################### 49  T=160
>>>>pa4b5P Pa6b5p ra2a6 Nd6b7 bc5f8B Qe8f8b ng3f5 Ra8a6r ra1a6R Rc8b8
>>>>11(6) #[axb5](49)#[Nf5](50) 50  T=308
>>>>ng3f5 Nd6f5n pe4f5N Pb5a4p bc2a4P Bd7a4b ra2a4B Qe8d7 bc5f8B Rc8f8b pf5f6 Qd7d5p
>>>
>>>Very confusing is whether it's a 11 ply PV or 12 ply pv.
>>
>>
>>What is the confuision.  Hsu said "11(6) means 11 plies nominal in software,
>>6 more plies in the chess chips."  What can _possibly_ be confusing about
>>that?
>
>
>Then Hsu is a big liar:


based on what???


>
>
><ch> 'c'
>---------------------------------------
>-->  1.   e4 <-- 39/119:51
>---------------------------------------
>Guessing c5
> 3(4)[Nf3](30) 30^ T=1
>ng1f3 Qd8c7
> 3(5) 38  T=2
>ng1f3 Nb8c6
> 4(5) 38  T=2
>ng1f3 Nb8c6
> 5(5)[Nf3](52) 52  T=2
>ng1f3 Nb8c6
> 6(5)[Nf3](68) 68  T=4
>ng1f3 Nb8c6 nb1c3
> 7(5) #[Nf3](68) 68  T=5
>ng1f3 Nb8c6 nb1c3 Ng8f6
> 8(6) #[Nf3](59) 59  T=6
>ng1f3 Nb8c6 bf1b5 Qd8b6 nb1a3
> 9(6) #[Nf3](66) 66  T=8
>ng1f3 Nb8c6 nb1c3 Ng8f6 bf1e2 Pd7d6
>10(6) #[Nf3](53) 53  T=18
>ng1f3 Nb8c6 bf1b5 Ng8f6 pe4e5 Nf6g4 bb5c6N Pd7c6b
>11(6)<ch> 'e5'
>---------------------------------------
>--> Pe7e5 <--
>---------------------------------------
>
>the 11 ply PV here doesn't show 11 ply or more. Knowing that
>at least 3 moves in this pv get extended it's very questionable
>whether they searched more as 5 ply in software here apart
>from the extensions.


So what?  For every such PV you show that is short, I can show two that
are normal.  I get short PVs all the time.



>
>the 7(5) pv : ng1f3 Nb8c6 nb1c3
>
>at the start of a game with 30 SP processors and probably sufficient
>hash, does that look like a 12 ply PV to you?


want me to post some 14 ply searches with a 2 ply PV from crafty?  Got
plenty of them...



>
>To me it looks like a 2 ply PV + 1 pv extension and 5 ply in hardware...
>
>Don't tell me that every game they had bugs in hashing :)
>
>Best regards,
>Vincent
>
>
>
>>
>>>
>>>the moves with n or N behind it means captures. DB extends in software
>>>nearly all captures. I see around 3 non capturing moves here.
>>
>>Where do you get that?  Their main extension is the singular extension.
>>Captures don't trigger that every time.
>>
>>
>>>
>>>So 5 or 6 ply in software + capture extensions
>>>(either recapture extensions or SE)
>>>+ 6 ply in hardware.
>>>
>>>Very logical.
>>>
>>>note it's a 12 ply PV you see here *not* a 11 ply pv.
>>
>>Vincent...   you are trying to make up the rules as you go.  I specifically
>>asked Hsu about the depth.  Your interpretation is totally off-the-wall and
>>irrelevant to the discussion.  He said that the 11 above means that the
>>software was started with a depth of "11", which would be reduced by one
>>for each ply searched, and extended as indicated based on their normal
>>extension logic.  When depth reaches zero, they then give that position to
>>a chess processor which then searches from that position for N plies, where
>>N in this case is 6 more.  The only difference is that singular extensions
>>don't happen in the hardware.
>>
>>The chess processors _can_ probe a hash table.  But he reported that he did
>>not have time to design a 16-port memory module for each chess board...  so
>>the 1997 version didn't do hash probes.  But only because he didn't have time
>>to do it, not because it is impossible to do.
>>
>>
>>
>>
>>
>>>
>>>I get way longer lines at 12 ply with extensions turned on as this :)
>>
>>
>>So what.  You don't have the same problem.  They used 32 processors.  A
>>single processor searched about 1/2 way thru the nominal software depth,
>>then positions were farmed out to 32 nodes on the SP (which use message
>>passing for communication and have distributed memory).  After depth goes
>>to zero, the remainder of the search was done by chess processors that have
>>_no_ hash memory, and _no_ PV facilities...  Which means they will _never_
>>see the part of the PV searched by the chess hardware.  And it is likely
>>that they will never see all of the software PV since the PV was searched
>>by different processors with no shared hash...
>>
>>Looking at the length of the PV is meaningless, and I have pointed this out
>>before.  They can _not_ get a PV from the chess hardware.  _period_.  It is
>>simply impossible as it was not designed into the processors, and with no
>>hash table, there is no other way to do it...
>>
>>
>>
>>
>>
>>>
>>>>qf2g3 Pg7g5
>>>>---------------------------------------
>>>>-->  33.   Nf5 <-- 7/65:41
>>>>---------------------------------------
>>>
>>>This is caused by 30 diff processors with SE implemented.
>>>I have those huge lines too in DIEP when i turn on all extensions!
>>>
>>>No big deal.
>>>
>>>If 6(6) would mean 6 ply in software and 6 ply in hardware,
>>>then why do we see only 5 ply line?
>>
>>See above.  I get short PVs all the time.  Since their hash is distributed
>>over 32 nodes, who knows what gets overwritten, and when...
>>
>>
>>
>>
>>
>>>
>>>Even if you overwrite on an SP computer you still get 6 ply!
>>
>>Nope.  They reconstruct PV from hash, since they can't back the PV up
>>from endpoints due to hardware.
>>
>>
>>
>>>
>>>Now the theoretic impossibility of searching 17 ply fullwidth
>>>*with* all those extensions the first 11 ply.
>>>
>>>Apart that each search line must be like 15 ply then or so,
>>>It's going to use up a lot of nodes.
>>>
>>>For deep blue it would cost around 5^6 more as the nodes they got in 1997!
>>>
>>>>Again I reiterate, the notation 11(6) means 11 plies in software search,
>>>>6 plies in the hardware, plus the quiescence in hardware.  There is _no_
>>>>argument with this.  Simply ask any of the DB guys.  11(6) is a total of
>>>>17 plies of search.
>>>
>>>Noop it is not Bob. It is 11 or 12 plies of search from which 6 ply
>>>in hardware. Makes sense. Logical and clearly visible from the lines.
>>>
>>
>>
>>No it doesn't.  You don't get to directly contradict the DB team, just because
>>you can't imagine how it could be done.  If half of the search were done by
>>the chess processors, you would _never_ see a 12 ply PV, since the chess
>>processors can't provide _any_ PV at all.
>>
>>
>>
>>
>>>The first few ply
>>>
>>>Note that if it would be 11 ply of search with pruning + 6 ply in hardware,
>>>then deep blue is the tactical worst program in history as it sees
>>>Bf5 in game 6 at 8(6) which would be 14 ply then, which doesn't make
>>>sense! Not even if you forward prune a lot!
>>>
>>>Shredder needs 8 ply for it too. It's a tactical queen win.
>>>Shredder is doing recapture extensions as far as i know.
>>>
>>>If i turn on extensions in diep i also need 8 plies. without recapture
>>>extensions i need 9 or 10 ply.
>>>
>>>Idem for other progs!
>>>
>>>Best regards,
>>>Vincent
>>>
>>
>>So?  Db is not "other progs"...



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