Author: Vincent Diepeveen
Date: 17:26:30 09/02/02
Go up one level in this thread
On September 01, 2002 at 12:08:21, Uri Blass wrote:
Uri, i posted my answer at 11:55, you answerred at 12:08.
That's 13 minutes.
How the HELL can you have looked up MTD in the meantime,
what it is and what it is doing, and where are your experiments
with MTD?
For MOVEI it sure works as long are your eval is stupid.
It would remove a lot of discussion about fritz here too.
like the stupid comments you don't nullmove in your PV.
WHICH PV DO YOU TALK ABOUT?
What kind of nonsense do you do in your program.
CODE PLEASE.
In fritz it's very easy i bet:
int mtd() { // of course with a goto instead of a very slow function call
// hashtable probe
if( depth <= verysmalldepth ) {
lookupfasthahstable(L1 cache) // L2 cache lookup too slow of course
return(qsearch(bound)); // of course no function call but a goto, faster...
}
else if( depth < mediumdepth ) {
lookupslowhashtable(L2 cache); // main memory factor 100 slower
else // depth movei nevergets
lookupveryslowmemory(main memory);
// no returns of course in case of a truebound, because returns are too
// slow. Only a jump
if( !incheck )
TryNullmove(); // best move to make first
I AM MISSING WHY HE WOULD NOT NULLMOVE. LOOK YOUR COMPARE IN C IS
ALREADY SLOWING DOWN FRITZ TOO MUCH. THE THING IS LESS THAN 2000 CLOCKS
A NODE WITH A BIGGER EVAL THAN CRAFTY,
DO YOU REALIZE HOW LITTLE THAT IS, 25 CLOCKS FOR MISPREDICTION HE CANNOT
AFFORD. TOO EXPENSIVE.
>On September 01, 2002 at 11:55:32, Vincent Diepeveen wrote:
>
>>On September 01, 2002 at 10:20:08, Uri Blass wrote:
>>
>>if you search for aske plaat you will find his stuff on
>>mtd online probably. i'm amazed that you don't understand
>>that Frans is using nullmove.
>
>I know that he is using null move but I do not use null move when I search the
>line that is in the previous pv because I consider it a waste of time.
>
>Null move is for prunning illogical lines.
>
>The pv cannot be illogical line so the only case when I can save nodes by null
>move pruning when I am in a pv line is when the position is zugzwang.
>In other words I can save nodes only if null move pruning is wrong.
>
>I understood that MTD says that the pv may be wrong but the first ply of the pv
>is always right so it does not make sense to prune after Nc6.
>
>Uri
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