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Subject: Re: simple proof of > 2.0

Author: Robert Hyatt

Date: 12:01:55 09/04/02

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On September 04, 2002 at 14:49:53, Vincent Diepeveen wrote:

>On September 04, 2002 at 14:24:47, Robert Hyatt wrote:
>
>With YOUR method it is very easily possible to get always
>> 2.0.
>
>The easy case is a program that gets a speedup of about 1.9
>and profits just a bit more than 5% from a filled hashtable.
>
>That's by definition > 2.0 then.

No, that is by hand-waving > 2.0.  Because the serial search would
_also_ profit by the filled hash table and run faster.

Try again...

>
>I need to add that you also have to search in the time of the
>opponent.
>
>Easy scenario. Suppose you take 24 positions. 1 position you
>get say 1.9 speedup (cleaned hashtable). The other 23 positions
>you mispredict the move. However the move is a transposition to
>the search tree the program plays.
>
>Then the moves get played and you start a new search with that hashtable.
>
>So you get like > 10 ply out of hashtable directly.

So?  So does the one-processor test and it all recalibrates nicely...


>
>That saves n minutes calculation where you calculate n minutes 50% of
>your search is for free then. I don't need to mention speedup is
>about 2x 1.9 = 3.8 then at 2 processors when compared to someone using
>a cleaned hashtable each time getting a 1.9 speedup.

Nobody does that.  My speedups are calculated consistently, unlike the
mish-mash crap you do above.  If the one processor test uses exactly the
same approach as the 4 processor test, then the four processor test doesn't
get any "gain" from hashing that the one processor test doesn't also get...

Stop waving your hands.  You look absolutely ridiculous.



>
>The average speedup is then : (23 * 3.8) + 1.9 = 3.72
>this at 2 processors.


If I compare the speed of a two processor search to the speed at which
a stump-grinder can grind stumps, I get a speedup of > 1,000,000.  Not
that the comparison makes much sense.  But it makes as much sense as your
rambling above...







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