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Subject: Re: I think I missed something

Author: Pham Minh Tri

Date: 16:06:48 12/08/01

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On December 07, 2001 at 23:52:37, Robert Hyatt wrote:

>On December 07, 2001 at 18:13:18, William Bryant wrote:
>
>>
>>>I was seeing an error 400K-500K nodes, on my PIII/750 laptop, which is about
>>>one error every 2 to 4 seconds.  On my quad (I didn't run the test there as it
>>>was playing on ICC) this would turn into an error every second or less, which
>>>is not acceptable.  Some positions produced _many_ errors per second, when there
>>>were fewer pieces so that more pawn moves were being searched...
>>
>>I believe the thread was discussing the frequency of errors using a 32 pawn hash
>>key which in previous threads you said that, after testing, produced no
>>significant degree of collisions or errors.
>
>
>This was a mistake on my part.  My testing (no errors) was actually done several
>times, but prior to my conversion to 32 bit signatures for pawn hashing.  When I
>tested this at David's urging, the number of collisions was ridiculous...  I am
>now using 64 bits again.
>

Do you think 64 bits hashkey for pawntable still speeds up program? or is it
better to not use?

In my case, a simple pawn code program, use 64bits hash for pawn is slower than
not use (because I could save much time for making hashkeys, probing and
entering table). I am curious about others.



>
>>
>>If I read the above correctly, this implies that it does produce an unacceptable
>>level of errors?
>>
>>Or is this above error rate discussing the main hash table using a 32 bit key?
>>
>
>pawns only.   as explained above.
>
>
>
>>Would you please clarify.
>>Thank you.
>>
>>William



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