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Subject: Re: Eating Crow is good with Tobasco..

Author: Robert Hyatt

Date: 20:27:41 12/02/05

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On December 02, 2005 at 17:47:00, Tony Nichols wrote:

>On December 02, 2005 at 17:21:59, Robert Hyatt wrote:
>
>>It is time to stop this now.  The above is utter nonsense.  We don't "search"
>>hash tables.  Larger hash tables do not take longer to search, because we just
>>don't search them.  We randomly probe into them and either hit or miss, so the
>>size has absolutely no effect other than larger sizes hold more information
>>without requiring that older data be overwritten sooner.
>>
>>You are quoting nonsense...
>
>
>Hello,
>
> Is it safe to assume that you can't have too much hash? I mean, as long as you
>have the ram.
>Regards
>Tony


pretty much.  Beyond some point additional hash will not help.  But to see how
it helps, set it to something like 384K (yes 384 k bytes) and run a position for
say 10 minutes.   Record the highest depth reached and the time to reach that
depth.  Double the hash and re-run.  Keep doing this until it doesn't get any
faster.  You just reached the max needed for the 10 minute search time (10
minutes was just a number, pick anything you want).  You will see significant
speed improvements at first, but they begin to flatten out and eventually
doubling the hash doesn't change a thing any further.

If a program clears hash between moves (most do not) then this can be a bigger
issue with large hashes since they do take time to clear should that be
needed...



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