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Subject: Re: Why doesn't everyone .. ( Program for Dual Processing) ???

Author: Vincent Diepeveen

Date: 09:02:31 04/04/02

Go up one level in this thread


On April 04, 2002 at 03:39:13, Uri Blass wrote:

>On April 03, 2002 at 20:22:02, Vincent Diepeveen wrote:
>
>>On April 03, 2002 at 15:00:05, Uri Blass wrote:
>>
>>I do not agree. 2 processors is for free getting nearly 2 times
>>faster.
>>
>>If that requires effort, it is a peanut compared to the effort
>>of writing a very efficient search.
>>
>>If you have a very efficient search, then again the argument is
>>even harder: getting nearly 2 times faster is making your thing
>>2 times faster than the opponent.
>>
>>This removes simply disadvantages as being a slow searcher
>>(in my case). I'm always faster than the guys who do not manage
>>to get dual CPU.
>>
>>then let's talk about price. the fastest single cpu liquid cooled CPU
>>is always slower for DIEP than DIEP at a dual CPU, whereas everyone
>>understands that liquid cooled VAPOCHILL a look like stuff and the
>>latest CPU is nearly impossible to get for me. Not to mention
>>unaffordable (also hard to get is a chip that is fast AND overclocks well).
>>
>>In short being SMP removes always the 'i need to invest just too much
>>money for this world champ' argument.
>>
>>If i show up tournaments with a dual 1.2Ghz K7 (which is pretty likely),
>>then i could perhaps for the world champs upgrade it pretty cheap to 1.5Ghz
>>dual K7 (above those speeds i already tried, the power supply doesn't
>>give enough power for speeds above 1.5Ghz so i would need more money then
>>to buy an expensive and better E-ATX PSU).
>>
>>Anyhow. Easier is just put in 1.4MPs pretty cheap upgrade. i'm nearly 3Ghz
>>then (when talking about K7). a dual 1.4Ghz K7 is the same speed for DIEP
>>like a P4 at about 6Ghz.
>>
>>So whatever you put single cpu against me, i'm faster simply. All those
>>thousands of dollars you can invest for latest cpu. If you are dual
>>you CAN be fast for little money (doesn't take away that usually
>>you then also invest for expensive CPU's to be even faster, but
>>that's other thing).
>>
>>We all know how hard it is nowadays to improve search. It is nearly
>>impossible with a search to beat nullmove + efficient qsearch + nullwindow
>>search (PVS).
>>
>>Of course you can shout about forward pruning, but before you get that
>>to work you are 8 years further. Even then it is always doubtful it
>>works at tournament level (considering you already get like 12 ply
>>easily with just nullmove + well written qsearch).
>>
>>So let's assume that someone has put 8 years of his time in improving
>>search, in fact most time is dedicated by most programmers in
>>search improvements (amazingly i have to admit that even in DIEP
>>half of my time still goes to search experiments).
>>
>>Suppose that someone manages to get a 5% node improvement by some kind
>>of search improvement. He earns a nobel prize of course then if it is
>>lossless (lossy is pretty risky and needs years of testing before it
>>can be aproved working for him).
>>
>>Now compare that with the Huber algorithm which every good programmer
>>who has a chessprogram can implement within a few days of his time.
>>Another week debugging and he'll get easily a 1.6 speedup.
>>
>>How can you *ever* say that improving the search of the engine
>>is smarter to do, considering that most programmers i know are
>>basically busy with search and NOT other things.
>>
>>for an investment of at most 2 weeks and new hardware, you get nearly
>>2 times faster. I don't know a single thing that can speed you up
>>that much!
>>
>>Of course you can go shout about hashtables and nullmove and pondering
>>in the time of the opponents, but it is
>>pretty idiotic to assume that someone doesn't use these known things.
>
>There are a lot of engines that do not use
>at least one of these things.
>
>My engine does not use null move, hash tables or pondering and has almost no
>evaluation and no book and has almost
>no knowledge in the evaluation(for example it's knowledge
>about pawn structure is only to punish pawns on the same file and it knows
>nothing about weak pawns or passed pawns).

but engines like Tiger, Gandalf have all that.

>Inspite of these problems it could draw 3-3 with
>another new Israeli engine(Genesis) when Genesis is using null move
>and hash tables.

nullmove is very easy to make.

>See http://f11.parsimony.net/forum16635/messages/24414.htm
>for the games.
>
>I believe that the search rules can be improved
>significantly without null move or hash tables.

it is insane to consider not using hashtables.

>Uri



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