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Re: Slowdown in longer hash keys

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From:
Aristotle Pagaltzis
Date:
August 26, 2012 04:11
Subject:
Re: Slowdown in longer hash keys
Message ID:
20120826111133.GA10373@fernweh.plasmasturm.org
* demerphq <demerphq@gmail.com> [2012-08-25 18:05]:
> Actually this reminds me. Sometime back there was a thread on maybe
> changing the hash algorithm to something faster or better.
>
> http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2006-05/msg00261.html
>
> Maybe we should revisit that one day.

Another avenue: make the constant-time complexity of hash lookups be
even more constant: <http://en.wikipedia.org/wiki/Cuckoo_hashing>

(That would also make degenerate-performance cases of the same impact as
on the current algorithm *at least* drastically harder to construct even
without randomisation or other unpredictability thrown in.)

Regards,
-- 
Aristotle Pagaltzis // <http://plasmasturm.org/>

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