Possibly changing the path encoding format

Noel Grandin noel at peralex.com
Sun Sep 23 05:12:48 CDT 2012


On 2012-09-21 19:17, Bryan O'Sullivan wrote:
> On Fri, Sep 21, 2012 at 12:39 AM, Noel Grandin <noel at peralex.com 
> <mailto:noel at peralex.com>> wrote:
>
>     Since this isn't a crypto application, you're probably better off
>     with a cheaper hash function like murmur hash, for which there is
>     both C and Python code:
>
>
> It's not a crypto application, but collisions would be catastrophic. 
> Functions that produce smaller hashes are obviously much more 
> vulnerable, and murmur in particular is problematic due to having poor 
> collision properties on some easily produced families of inputs.

Non-crypto hashes are not defacto smaller, nor are they more likely to 
produce collisions. They are just cheaper to compute.
And Murmur appears to have fixed it's collision issues in Murmur3.
But if what you mean is that you'd like 256 bits in your hash result 
instead of just 128, then CityHash is probably a good choice.
http://code.google.com/p/cityhash/



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