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Subject: Re: Oops...

Author: Robert Hyatt

Date: 18:37:09 05/02/00

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On May 02, 2000 at 21:00:11, William Bryant wrote:

>On May 02, 2000 at 18:55:15, Robert Hyatt wrote:
>
>[big snip]
>>
>>simplicity.  I want a power of 2 for the size.  which means that one has to
>>be 1/2 the size of the other, to let the hash table take up 3/4 of memory
>>and still be a power of 2.  I tried making the depth-prefered table bigger,
>>then tried it smaller.  Smaller was more efficient, by a fairly small amount.
>>
>>The alternative would be a combined table with (say) 3 entries per bucket,
>>with the first being depth-prefered, the last being always store, and the
>>middle one a place to save whatever the other two overwrote.
>>
>
>As I understand it, the idea with the dual entry hash table is that each
>hash address holds two hash enteries, 1 depth prefered, 1 always replace.
>
>Wouldn't this make both tables "the same size"?
>
>Or are you using two different tables and indexing into each one independently?
>
>William
>wbryant@ix.netcom.com


two tables.  one of size N, one of size 2*N.  The reason is to get around
using only 1/2 of memory for the hash table, while keeping a power of 2 size.
This allows 3/4 of memory for hashing.



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