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Subject: Re: Hash Table Collisions

Author: Colin Frayn

Date: 06:37:55 04/12/00

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> Even if you don't hash qsearch nodes, 5K/s is very little. Are you sure you
> hash every exit from your searchfunction ?

Yeah.  That seems like a reasonable amount to me.  Quite a few are just going to
be discarded as they aren't deep enough or they will replace existing nodes if
they are deeper, so I don't count them as new entries.  I only hash entries from
level 1 and shallower to ensure that they are worth storing. (i.e. not leaf
nodes or qsearch).

>Add a 1
>bit aging variable. If you or your opponent makes a move, set all these bits in
>your hashtable. When you're searching and find an entry with the bit set it
>means: Information is still usefull, but you can overwrite it whenever you want
>because it's from a previous search.

Yeah I know how it's done, I just never bothered.  I suppose I could make it so
that it's only an optional extra and perhaps only works in Xboard mode or
something.  I don't entirely know yet, but I'll almost certainly add something
in for the next version. The way I organised the data structures I think that it
might be rather difficult.  Not sure though - it might be ok....

Cheers,
Colin



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