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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Good hash for pointers
Date: Wed, 05 Jun 2024 21:40:27 -0700
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Michael S <already5chosen@yahoo.com> writes:

> On Wed, 05 Jun 2024 08:58:46 -0700
> Tim Rentsch <tr.17687@z991.linuxsc.com> wrote:
>
>> I did get your own hash function out and put it into my little
>> test rig.  There may be summary comments below.
>
> <snip>
>
> As you probably already paid attention, I like bottom lines.
> What is a bottom line here?

The bottom line is both the multiply-by-a-large-prime hashes
should be avoided.

> Did you you encounter cases in which almost-bonita's-but-not-quite
> hash function performed badly?

Yes.  A clear example is using directly mapped hash table that
has a power of two elements, with inputs all from malloc( 48 )
calls.  All keys map to one of only 1024 entries, in a hash
table that has 65536 slots.