Re: [PATCH 0/1] Rosebush, a new hash table

From: Herbert Xu
Date: Sun Feb 25 2024 - 00:53:52 EST


On Sun, Feb 25, 2024 at 12:51:06AM -0500, Kent Overstreet wrote:
>
> but your distribution actually is accurate in general, golden ratio hash
> is relly nice for sequential integers. the actual problem with your test
> is that you're testing 100% occupancy - no one does that.
>
> 75% occupancy, siphash:
> 0: 933
> 1: 60
> 2: 6
> 3: 1
> 4: 0
>
> that looks about right to me.

The point is that the worst-case length grows with the size of
the table so it won't always be 3. You need to take into account
the largest table size that you will support.

Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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