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Subject: Re: Status of Brutus?

Author: Robert Hyatt

Date: 21:31:17 07/28/03

Go up one level in this thread


On July 28, 2003 at 20:59:24, Vincent Diepeveen wrote:

>On July 28, 2003 at 19:16:08, Keith Evans wrote:
>
>>On July 28, 2003 at 16:52:29, Vincent Diepeveen wrote:
>>
>>>On July 28, 2003 at 16:45:33, Keith Evans wrote:
>>>
>>>>On July 28, 2003 at 13:36:09, Vincent Diepeveen wrote:
>>>>
>>>>>Just compare the design of the move generator of Hsu with chrilly. It is a
>>>>>*massive* difference already.
>>>>
>>>>There are other statements that you made that I could discuss, but this one
>>>>caught my eye...
>>>>
>>>>What are you talking about? What's the difference? How do you know? You seem to
>>>>be implying that Chrilly did a better job than Hsu which I don't believe.
>>>
>>>Yes massive better.
>>>
>>>Hsu has written many articles.
>>>
>>>here is a summary of what Chrilly has said in way more words (voice)
>>>when he was staying here for a few days:
>>>
>>>  Hsu was one of the first to make a move generator. He didn't write it in
>>>  verilog but in the direct logics of the chip. Very incompatible method.
>>>  Custom made by hand. It is incredible that he managed to write at such a
>>>  low level anyway. However, a bad result from writing at such a low level is
>>>  that the scale and size of the logics is so big that he must have
>>>  lost oversight. I write in a more compatible language called Verilog and
>>>  that is not comparable to C but way closer than the very 'assembly' way
>>>  in which Hsu has written his logics at. It means in short that Brutus
>>>  move generator therefore is very small. Note that i MUST make it small
>>>  because i am commercial and more gates is more money to pay for. In the
>>>  first chip i had just 50000 gates in total and that is very very little to
>>>  get a chessprogram working in.
>>>  From my viewpoint all the things i have seen so far is utmost beginners
>>>  level. This is logical, They are hardware designers, not chessprogrammers.
>>>  I focus upon the chess programming technical result. They had so much other
>>>  problems to deal with from hardware viewpoint that we can not even compare
>>>  it in that sense.
>>>
>>>Best regards,
>>>Vincent
>>
>>I only know of a few architectures that have been used for building hardware
>>move generators.
>>
>>1 - the Hitech style approach which is going to be very large. (Even with the
>>latest and largest FPGAs I don't think that you would get 64 Hitech chips into
>>one FPGA. It needs a ton of registers.)
>>
>>2 - the Belle style approach which returns moves in an MVV/LVA order and
>>potentially based on centrality - hardly random but not SEE. Despite what
>>Chrilly allegedly said, Hsu built an efficient move generator. You could fit a
>>lot of those on the latest chips at 0.18 micron or below - much more efficient
>>than anything going in an FPGA in terms of silicon area. It would also run quite
>>fast. Hsu suffered through doing a hand layout, but the result was a really
>>small move generator that would probably run insanely fast on today's
>>technology.
>>
>>3 - some obscure architectures which had basically random move ordering. (You
>>can find references in Ebeling's book.)
>>
>>Now from what you're saying I infer Chrilly came up with his own architecture.
>>Do you have any idea what makes it novel? From what you're saying he's not
>>planning on more than 2-3 plies of search in hardware so maybe he has a really
>>simple move generator that has basically random move ordering?
>>
>>-K
>
>ok here is facts
>  a) DBII was more advanced than other tries like belle and some studentish
>tries.
>
>What you find efficient perhaps in commercial terms is still terrible
>inefficient. Some people are happy for example with bitboard move generator in
>software. Well at 32 bits architecture i'm 2.2 times faster generating moves
>than crafty. In fact around 73 million a second after 1.e4,e5 2.d4,d5 at a
>2.127Ghz K7.
>
>That's including general code (so my move generator is not written out for white
>and black, it is general code) and of course storage of moves and ordering
>scores to the RAM.
>
>That's how you must compare brutus and deep blue with each other.
>
>both come from a different time zone.
>
>It is like comparing a sniper rifle from 2003 with a sniper rifle from world war
>1.
>
>Distances they shot at in world war 1 and 2 with sniper rifles must have been a
>few hundreds of meters.

In WW1 my grandfather was a sniper.  He shot at ranges up to 1000 yards.

In WW2 my father was a sniper.  He shot at ranges up to 1000 yards.

Today, a neighbor down the street is a sniper.  He shoots at ranges up to 1000
yards.

_nobody_ shoots a sniper rifle at ranges of "kilometers" today.  "kilometer"
perhaps.  With an occasional attempt at up to 2km with a big 50 cal "rifle".

This is just another area where you know nothing, but write as though you are
an expert.

BTW, Hsu's move generator is _not_ a lot better than Belle.  All you have to
do is read his paper to see what he did...


>
>Snipers now practice ranges of kilometers now with a single rifle.
>
>Deep Blue was created in a time that search efficiency was not important simply
>because search depths were very small. At 8 ply search depth it doesn't matter
>whether you have branching factor 6 or 8.
>
>What matters is tactics.
>
>In hardware advantage is brute force. Optimizing the thing for efficiency was
>simply not needed. Hashtables were considered new. Nullmove considered dubious
>if you used it anyway.
>
>A normal cpu's only a few had a big RAM.
>
>I remember Schach 3.0 from around 1997. That with hashtables up to 32 megabytes
>(really a lot in those days) and it had singular extensions and of course
>nullmove R=2.


I assume you mean 1987.  We played them in 1983.  In 1983 32 megabytes was
_not_ really a lot to _some_ of us...

>
>But despite all those toys it had a branching factor of 10.0.
>
>Who cared? it outsearched everyone single cpu. It got 10 ply easily with a
>quarter of a million nodes a second at a 133Mhz P5.
>
>Yes that's < 600 clocks a node.
>
>But if you can get 250k nps who cares for b.f. = 10 ?
>
>Now where everyone suffered from speed versus knowledge problems and only some
>commercial programmers started to slowly agree in one of the many discussions at
>the Aegon tournament 1997 that above 10 ply search depths the piece square table
>programs would get outdated as they simply didn't play better (of course
>assuming updating only in the root and only using those psq) it was trivial in
>those days that everyone suffered from tactical problems.
>
>I remember how i in BLITZ could trick them. Yes in 1997. In blitz if a trick
>looked to mee pretty deep, then i would gamble at it and win as they fell for
>it.

I've offered you the chance to put up and prove that statement, more than
once.  I used a P6/200 in 1996.  I'll use a P6/200 today in a blitz match
against you to let you "show" your blitz skills.

You hardly won a game back then.  You'll hardly win a game today.  Stop
stretching the truth so far that you look ridiculous.


>
>Only the best commercial programs in those days, with very very little
>chessknowledge inside could get through the tactical barrier just *a bit*.
>
>Remember fastest PC processor in 1997 was the not yet sold and very experimental
>PII-300Mhz.

That's baloney.  I had a _dual_ PII/300 in 1997.


>
>Of course there were also alpha's 21164 at 633Mhz experimental (and overclocked
>with kryo to 767Mhz at -40C at world champs Paris 1997).
>
>So basically the programs which were not piece square table based were
>struggling incredible to play tactical a bit better. I remember how with a lot
>of effort i searched 8 ply in world champs 1997.

Strange.  I searched 11-12 plies in 1996 in Jakarta.  And in 1997 in Paris.


>
>I remember how happy i was that Fritz thought for a long period of time against
>DIEP at a critical moment when diep was predicting the correct move.
>
>Only because of that fritz thought for 12 minutes, diep could reach the
>INCREDIBLE DEPTH of 10 ply. So the losing move it had planned at 8 and 9 ply
>failed low at 10 and it played a move that saved the game there.
>
>Imagine my happyness reaching 10 ply back then in the ENDGAME after 12 minutes
>of search.
>
>Most programmers therefore were dubiously forward pruning. From which Rebel is
>best example. See how buggy all the forward pruning is as posted at the
>homepage. Brilliant for 1990 perhaps. But even in 1997 it was looking dubious.
>
>Nullmove by Hyatt & co was considered just another dubious form of forward
>pruning.

Eh?  Everyone was using it in 1996.  Me.  Bruce (Ferret).  Fritz.  I don't know
of many that were not, in fact.


>
>Now comes deep blue which searches 10 ply fullwidth with a bunch of extensions.
>So that's called 12.2 ply then (extensions are simply added to the iteration
>depth). Let's be clear it did *not* search on average 12.2 ply. Its iteration
>depth was like 11 ply on average at most. More like 10.9 ply
>
>But it extended all checks. It extended loads of captures. Forced moves.
>
>So tactical it was equal to Schach at a 800Mhz PIII.
>
>However, there were no 800Mhz PIIIs at that time.
>
>So where 12 ply looks normal in 2003 as a depth which most programs get,
>in 1997 it was not a normal depth for programs doing a gnuchess a look like
>evaluation.
>
>Gnuchess was considered to be using a too heavy evaluation in fact. Mobility
>sucked ass because it slowed you down incredible. I remember at the time a
>statement of Frans about that.
>
>"only search depth counts, as you learn through search, not through evaluation".
>
>So deep blue chips not using killermoves in hardware is no problem. Inefficient
>search in hardware? no problem!
>
>Only the nodes a second counts!
>
>More nodes a seconds means more tactical strength!
>
>Gnuchess with singular extensions and checks in qsearch and more recapture
>extensions for sure will be finding the same type of tactics like deep blue and
>will agree with everything with deep blue positional spoken.
>
>But now we are in 2003.
>
>Search no longer can be done in a rude primitive way.
>
>Not even in hardware.
>
>Best regards,
>Vincent



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