Re: Question about tcp hash function tcp_hashfn()



On Thu, Jun 01, 2006 at 12:46:08AM -0600, Brian F. G. Bidulock (bidulock@xxxxxxxxxxx) wrote:
Since pseudo-randomness affects both folded and not folded hash
distribution, it can not end up in different results.

Yes it would, so to rule out pseudo-random effects the pseudo-
random number generator must be removed.


You are right that having test with 2^48 values is really interesting,
but it will take ages on my test machine :)

Try a usable subset; no pseudo-random number generator.

I've run it for 2^30 - the same result: folded and not folded Jenkins
hash behave the same and still both results produce exactly the same
artifacts compared to XOR hash.

Btw, XOR hash, as completely stateless, can be used to show how
Linux pseudo-random generator works for given subset - it's average of
distribution is very good.

--
Evgeniy Polyakov
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