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Subject: Re: Gandalf HASH notice for all!!

Author: Ulrich Tuerke

Date: 03:47:16 01/09/01

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On January 09, 2001 at 06:18:29, Steffen Jakob wrote:

>On January 09, 2001 at 05:36:26, Ulrich Tuerke wrote:
>
>>On January 09, 2001 at 04:55:19, Jouni Uski wrote:
>>
>>>On January 09, 2001 at 04:08:38, Ulrich Tuerke wrote:
>>>
>>>>On January 09, 2001 at 03:09:39, Jouni Uski wrote:
>>>>
>>>>>If I am not complete wrong please note:
>>>>>
>>>>>Because Gandalf is so slow in NPS sense (about 1/4 of many top engines) it needs
>>>>>much less HASH table RAM than other programs and if You give too much HASH it
>>>>>weakens engine! So my recommendation:
>>>>>
>>>>>  500 Mhz PC 32MB
>>>>> 1000 Mhz PC 56MB
>>>>>
>>>>>The readme.txt to use 104MB for >128MB PC is not wise at all.
>>>>>
>>>>>Jouni
>>>>
>>>>I don't see, why "too much" hash could do any harm.
>>>>Uli
>>>
>>>I am not sure may be there is minor bug in hashing code. With 104MB (or similar)
>>>clearing of hash seems to take 5-10 seconds in my PC!
>>
>>This sounds weird. You shouldn't need 5-10 seconds for memory operations.
>>Perhaps your hash size is too close to your memory size and Windows starts
>>paging ?
>
>It depends if you simply clean the whole memory with zeroes or if you set a flag
>for each hash entry. In that case it is indeed better not to use large hash
>tables if you are low on time (e.g. in bullet games).
>
>Best wishes,
>Steffen.

Come on, 5-10 seconds ! This must be massive hard disk access. A "memset" for
hundreds of MB can't take that long.



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